The Rise Of Civilization And Ancient Civilizations

The rise of civilization has always fascinated people. Since the appearance of anatomically modern human beings, some one hundred and fifty thousand years ago, the emergence of civilization has been one of the most important accomplishments of people. Civilization is defined as â€Å"an organizing principle that implies common institutions, economic systems, social structures, and values that extend over space and time† (Matthews 3). Some of the things that make up a civilization are religion, government, arts, writing and language, currency, study of science, math and medicine - as examples. The two earliest known civilizations were Mesopotamia and Egypt. These two civilizations arose around the same time and coincidentally near one another, near the Mediterranean Sea. Many similarities and differences exist between these ancient civilizations. In particular, the religions of these two civilizations are distinguishably different, yet have many concrete similarities as well. The religions of Mesopotamia and Egypt are the products of the environment that the people lived in and their experiences living in it. Because of the harsh and unpredictable nature of their environment, the religion of the ancient people in Mesopotamia was very pessimistic. They lived only at the mercy of their gods, who they believed were of great power and controlled the environment. In ancient Egypt, contrastingly, nature was far more stable and predictable. It was thusly believed that the gods favoredShow MoreRelatedFactors That Affect The Rise And Fall Of Civilizations Essay914 Words   |  4 PagesEffect the Rise and the Fall of Mayan Civilization Area and Egyptian Civilization Area In ancient time, environmental factors were very important. It directed the people to where they should settle to practice agriculture for their living. Among many different important environmental factors such as geography, geology, plant and animal species, agricultural potential, resource abundance, one of the most significants factors which influenced to the rise and the fall of civilizations is climateRead MoreRiver Valley Civilizations Essay726 Words   |  3 PagesAncient river valley civilizations are one of the earliest societies in the world. The rises of these ancient river valley civilizations started the first cradle of civilization. The Indus Valley Civilization, Ancient Egypt, Ancient Mesopotamia, and Ancient China are the earliest civilizations that were successful enough to make enough food for everybody. Every one of these civilizations had three things in common: they all had a special relationship with the river, they created their own writingRead MoreA Brief No te On The Civilization And The Indus Valley Civilization860 Words   |  4 Pagessigns of urban life. 2. Indus Valley civilization: The Indus Valley civilization is located in present day Pakistan. This civilization had evidence to provide little indications of no political hierarchy or centralized. 3. Central Asian/ Oxus civilization: A civilization that was economically based on irrigation agriculture and stock raising. This civilization was a focal point of a Eurasian-wide system of intellectual and commercial exchange. This civilization started to fade away by 1700 B.C.ERead MoreWomen s Status Of Inferiority1405 Words   |  6 Pagesmaking them be seen as â€Å"property† (Ahmed 12). In many instances, the rise of urban societies negatively affected women as Leila Ahmed stated in â€Å"Women and Gender in Islam† and as demonstrated in late Sumerian, Babylonian, and Assyrian cultures. The complexities of these civilizations produced military competitiveness, escalating the aspects of male dominance and classes that further demeaned women (Ahmed 12). However, the rise of Islam rectified the unjust social constructs as women were given moreRead MoreEgypt : The Egyptian Civilization920 Words   |  4 PagesEgypt was never like that today. This essay well talk abou t the development of Egyptian civilization by explaining the prehistory of Egypt and identifying three cultural developments or political events that were important to the rise of Egyptian civilization. Also, explaining what happened and why it was important or significant to the rise of Egypt. Egypt is known to be one of the longest lasted civilization in the world. It is located in the Nile Valley, in the north east of Africa. Its originsRead MoreAnalysis Of Ruins Of An Ancient City, By John Martin1456 Words   |  6 Pagesthat would spread throughout Europe, the United States, and Latin America. The characteristics typical of Romantic painting consist of landscapes, freedom, and beauty. John Martin s Ruins of an Ancient City, completed around 1810-1820, depicts desolate ruins that remind us that all civilizations will eventually collapse. In its wake, a new culture will develop out of the previous one, with or without knowledge of the past. The piece implicitly shows that the ruins serve as a place of sightseeingRead MoreThe Romanticism Of The 19th Century1289 Words   |  6 Pagescharacteristics typical of Romanticism consists of landscapes, freedom, and beauty. John Martin s Ruins of an Ancient City, completed around 1810-1820, depicts desolate ruins tha t remind us that a civilization will eventually collapse due to the passage of time. In its wake, a new culture will grow out of the previous one, but it will require knowledge of the past to develop. All knowledge of civilization is not erased completely from history; it is documented through the use of observation, preservationRead MoreThe Impact of the Egyptian and the Hebrew Civilizations on Humanity1459 Words   |  6 PagesIntroduction Throughout history, great civilizations have existed in various parts of the world. The cultural, economic, political, and/or intellectual achievements of these civilizations contributed to the advancement of humankind. Civilization is a term that has various meanings. Most popularly and in this context it can be referred to as an advanced state of human society, in HYPERLINK http://dictionary.reference.com/browse/which which  a high level of HYPERLINK http://dictionary.referenceRead MoreTaking a Look at Ancient Egypt1181 Words   |  5 PagesThe first ever civilization in Africa was in Egypt along the river Nile. This civilization later spread to the other parts of Africa. The emergence of civilization in Africa provided a framework for most of developments in African history. There were different setups cultural and political aspects when civilization was emerging. The Egyptian civilization was the earliest and it was one of the catalysts in the development of civilization in other parts of Africa. The civilization began around 3000Read MoreThe Yellow River And The Chinese Nation1405 Words   |  6 Pagesby almost all Chinese people that it is the cradle of Chinese civilization and the spiritual home of the Chinese people (Zhou). The Yellow River is the symbol of the Chinese nation, the spirt of the Chinese people, but most importantly civilization itself. The Yellow River gets its name from the yellowish color of the water. The water is yellow because each year over 1.6 billion tons of soil flows into the river, which causes the rise and shifting of the river bed (Wu). Before the damming of the

Coram, Robert Boyd The Fighter Pilot Who Changed the Art of War Free Essays

A biography of Col. John Boyd, Coram’s book reads much like the collection of interviews that it is. He gives the impression that if the reader happened upon any of these characters at happy hour, the stories would be identical. We will write a custom essay sample on Coram, Robert Boyd: The Fighter Pilot Who Changed the Art of War or any similar topic only for you Order Now Dispersed throughout the book is a supply of background information and context, glimpses and bits about family life, and a very understandable layman’s introduction to the scholarly work of John Boyd. Coram is an ex-newspaper man that has recently produced two military biographies. He lays out for his reader not only the successes of John Boyd, but the rough edges of the man as well. The brilliance that brought the engineering world the Energy-Maneuverability equations was balanced by Boyd’s egoism and anti-authoritarianism. Coram’s objective seems to be to reveal a principle regarding brilliant personnel: that they are invaluable to any organization, providing the leadership can stomach their idiosyncrasies. Coram sets his Boyd biography up in three sections: Fighter Pilot, Engineer and Scholar. The three sections are based on the three major accomplishments of Col. Boyd. As a fighter pilot, Boyd used his creative intellect to develop advanced techniques and tactics, based on his subconscious knowledge of the workings of maneuverability based on available energy. As an engineer, Boyd codified the principles of energy-maneuverability, and evaluated all of the fighter aircraft of the time using the equations he developed. This evaluation, although looked upon skeptically at the time, has been proven to be accurate, and the E-M theory continues to be used to both evaluate and design aircraft. As a scholar, Boyd evaluated decision-making and came up with the ODDA loop. (Observe, Orient, Decide, Act) This concept is a simple diagram of the decision making process, and has been disseminated widely, with variations, all the way from the military to driver training curriculum. A variation of the model is called IPDE; Identify, Predict, Decide, Execute. An old adage says that a man’s best work is done after 50, and I believe that John Boyd validated it. His Destruction and Creation essay, which Coram includes at the end of the biography, is a masterful assembly of the concepts of the Heisenberg Principle and Thermodynamics, applied to a type of his decision-making theory. Concepts of the present system of thought, combined with concepts from multiple other disciplines, can be creatively made into a composite that is more than the sum of the pieces used, and useful for further evaluation. This is essentially the synthesis used in the development of the E-M theory equations. Coram deals as respectfully as possible with the dysfunctional family life of Boyd. Several passages leave the reader deeply saddened that such a brilliant man could be at the same time so base. He also presents the distinct probability that Boyd’s personality and fighter-pilot approach to obstacles caused as many personal difficulties as it remedied. Coram also reveals the truth that presentation is paramount; as Boyd’s abrasive presentation of his ideas initially caused much individual resistance, and his masterful presentation of his ideas later on was the main reason that they became widely adopted. Altogether, a well written biography, that leaves my wishing I had sat thru at least a few happy hours with Col. Boyd and his associates, if only to hear the tall tales of a meritorious veteran warrior-scholar. Coram brings John Boyd to the reader as he was; brilliant, dauntless, abrasive, even offensive, but loyal to his cause and his message. He leaves the reader with the nagging question: Am I going to Do something, or be content to Be somebody? How to cite Coram, Robert Boyd: The Fighter Pilot Who Changed the Art of War, Papers

INTERNAL

INTERNAL-COMBUSTION ENGINE Essay INTRODUCTIONInternal Combustion Engine, a heat engine in which the fuel is burned ( that is, united with oxygen ) within the confining space of the engine itself. This burning process releases large amounts of energy, which are transformed into work through the mechanism of the engine. This type of engine different from the steam engine, which process with an external combustion engine that fuel burned apart from the engine. The principal types of internal combustion engine are : reciprocating engine such as Otto-engine, and Diesel engines ; and rotary engines, such as the Wankel engine and the Gas-turbine engine. In general, the internal combustion engine has become the means of propulsion in the transportation field, with the exception of large ships requiring over 4,000 shaft horsepower ( hp). In stationary applications, size of unit and local factor often determine the choice between the use of steam and diesel engine. Diesel power plants have a distinct economic advantage over steam engine when size of the plant is under about 1,000 hp. However there are many diesel engine plants much large than this. Internal combustion engines are particularly appropriate for seasonal industries, because of the small standby losses with these engines during the shutdown period. HistoryThe first experimental internal combustion engine was made by a Dutch astronomer, Christian Huygens, who, in 1680, applied a principle advanced by Jean de Hautefeuille in 1678 for drawing water. This principle was based on the fact that the explosion of a small amount of gunpowder in a closed chamber provided with escape valves would create a vacuum when the gases of combustion cooled. Huygens, using a cylinder containing a piston, was able to move it in this manner by the external atmospheric pressure. The first commercially practical internal combustion engine was built by a French engineer, ( Jean Joseph ) Etienne Lenoir, about 1859-1860. It used illuminating gas as fuel. Two years later, Alphonse Beau de Rochas enunciated the principles of the four-stroke cycle, but Nickolaus August Otto built the first successful engine ( 1876 ) operating on this principle. Reciprocating EngineComponents of EnginesThe essential parts of Otto-cycle and diesel engines are the same. The combustion chamber consists of a cylinder, usually fixed, which is closed at one end and in which a close-fitting piston slides. The in-and-out motion of the piston varies the volume of the chamber between the inner face of the piston and the closed end of the cylinder. The outer face of the piston is attached to a crankshaft by a connecting rod. The crankshaft transforms the reciprocating motion of the piston into rotary motion. In multi-cylindered engines the crankshaft has one offset portion, called a crankpin, for each connecting rod, so that the power from each cylinder is applied to the crankshaft at the appropriate point in its rotation. Crankshafts have heavy flywheels and counterweights, which by their inertia minimize irregularity in the motion of the shaft. An engine may have from 1 to as many as 28 cylinders. Fig. 1, Component of Piston Engines. The fuel supply system of an internal-combustion engine consists of a tank, a fuel pump, and a device for vaporizing or atomizing the liquid fuel. In Otto-cycle engines this device is a carburetor. The vaporized fuel in most multi-cylindered engines is conveyed to the cylinders through a branched pipe called the intake manifold and, in many engines, a similar exhaust manifold is provided to carry off the gases produced by combustion. The fuel is admitted to each cylinder and the waste gases exhausted through mechanically operated poppet valves or sleeve valves. The valves are normally held closed by the pressure of springs and are opened at the proper time during the operating cycle by cams on a rotating camshaft that is geared to the crankshaft . By the 1980s more sophisticated fuel-injection systems, also used in diesel engines, had largely replaced this traditional method of supplying the proper mix of air and fuel; computer-controlled monitoring systems improved fu!el economy and reduced pollution. IgnitionIn all engines some means of igniting the fuel in the cylinder must be provided. For example, the ignition system of Otto-cycle engines , the mixture of air and gasoline vapor delivered to the cylinder from the carburetor and next operation is that of igniting the charge by causing a spark to jump the gap between the electrodes of a spark plug, which projects through the walls of the cylinder. One electrode is insulated by porcelain or mica; the other is grounded through the metal of the plug, and both form the part of the secondary circuit of an induction system. The principal type of high-tension ignition now commonly used is the battery-and-coil system. The current from the battery flows through the low-tension coil and magnetizes the iron core. When this circuit is opened at the distributor points by the interrupter cam, a transient high-frequency current is produced in the primary coil with the assistance of the condenser. This induces a transient, high-frequency, high-voltage current in the secondary winding. This secondary high voltage is needed to cause the spark to jump the gap in the spark plug. The spark is directed to the proper cylinder to be fired by the distributor, which connects the secondary coil to the spark plugs in the several cylinders in their proper firing sequence. The interrupter cam and distributor are driven from the same shaft, the number of breaking points on the interrupter cam being the same as the number of cylinders. Cooling SystemBecause of the heat of combustion, all engines must be equipped with some type of cooling system. Some aircraft and automobile engines, small stationary engines, and outboard motors for boats are cooled by air. In this system the outside surfaces of the cylinder are shaped in a series of radiating fins with a large area of metal to radiate heat from the cylinder. Other engines are water-cooled and have their cylinders enclosed in an external water jacket. In automobiles, water is circulated through the jacket by means of a water pump and cooled by passing through the finned coils of a radiator. Some automobile engines are also air-cooled, and in marine engines sea water is used for cooling. StarterUnlike steam engines and turbines, internal-combustion engines develop no torque when starting, and therefore provision must be made for turning the crankshaft so that the cycle of operation can begin. Automobile engines are normally started by means of an electric motor or starter that is geared to the crankshaft with a clutch that automatically disengages the motor after the engine has started. Small engines are sometimes started manually by turning the crankshaft with a crank or by pulling a rope wound several times around the flywheel. Methods of starting large engines include the inertia starter, which consists of a flywheel that is rotated by hand or by means of an electric motor until its kinetic energy is sufficient to turn the crankshaft, and the explosive starter, which employs the explosion of a blank cartridge to drive a turbine wheel that is coupled to the engine. The inertia and explosive starters are chiefly used to start airplane engines. Patriotism EssayGas TurbineAlso called as combustion turbine, engine that employs gas flow as the working medium by which heat energy is transformed into mechanical energy. Gas is produced in the engine by the combustion of certain fuels. Stationary nozzles discharge jets of this gas against the blades of a turbine wheel. The impulse force of the jets causes the shaft to turn. A simple-cycle gas turbine includes a compressor that pumps compressed air into a combustion chamber. Fuel in gaseous or liquid-spray form is also injected into this chamber, and combustion takes place there. The combustion products pass from the chamber through the nozzles to the turbine wheel. The spinning wheel drives the compressor and the external load, such as an electrical generator. In a turbine or compressor, a row of fixed blades and a corresponding row of moving blades attached to a rotor is called a stage. Large machines employ multistage axial-flow compressors and turbines. In multi-shaft arrangements, the initial turbine stage (or stages) powers the compressor on one shaft while the later turbine stage (or stages) powers the external load on a separate shaft. The efficiency of the gas-turbine cycle is limited by the need for continuous operation at high temperatures in the combustion chamber and early turbine stages. A small, simple-cycle gas turbine may have a relatively low thermodynamic efficiency, comparable to a conventional gasoline engine. Advances in heat-resistant materials, protective coatings, and cooling arrangements have made possible large units with simple-cycle efficiencies of 34 percent or higher. The efficiency of gas-turbine cycles can be enhanced by the use of auxiliary equipment such as inter-coolers, regenerators, and reheaters. These devices are expensive, however, and economic considerations usually preclude their use. In a combined-cycle power plant, the considerable heat remaining in the gas turbine exhaust is directed to a boiler called a heat-recovery steam generator. The heat so recovered is used to raise steam for an associated steam turbine. The combined output is approximately 50 percent greater than that of the gas turbine alone. Combined cycles with thermal efficiency of 52 percent and higher are being put into service. Gas turbines have been applied to the propulsion of ships and railroad locomotives. A modified form of gas turbine, the turbojet, is used for airplane propulsion. Heavy-duty gas turbines in both simple and combined cycles have become important for large-scale generation of electricity. Unit ratings in excess of 200 megawatts (MW) are available. The combined-cycle output can exceed 300 MW. The usual fuels used in gas turbines are natural gas and liquids such as kerosene and diesel oil. Coal can be used after conversion to gas in a separate gasifier. Internal-Combustion Engines and Air PollutionAir pollution from automobile engines ( smog ) was first detected about 1942 in Los Angeles, CA. Smog arises from sunlight-induced photochemical reactions between nitrogen dioxide and the several hundred hydrocarbons in the atmosphere. Undesirable products of the reactions include ozone, aldehydes, and peroxyacylnitrates ( PAN ). These are highly oxidizing in nature and cause eye and throat irritation. Visibility-decreasing nitrogen dioxide and aerosols are also formed. Five categories of air pollutants and percent contribution from all transportation source and the highway vehicle subset are show in Table -1. Virtually all of the transportation CO, about half the hydrocarbons, and about one-third of the nitrogen oxides come from gasoline engines. Diesel engines account for the particulate. Table-1.Estimated Total Annual US Emissions from Artificial Sources (1980)Carbonmonoxide HydrocarbonsSulfuroxidesNitrogenoxides ParticulateTotal, teragram/yr.85.421.823.720.77.8All transportation, %81363.84418Highway vehicles, %72291.73214SOURCE: EPA Report 450/4-82-001, 1982. Emissions from internal-combustion engines include those from blowby, evaporation, and exhaust. These can vary considerably in amount and composition depending on engine type, design, and condition, fuel-system type, fuel volatility, and engine operating point. For an automobile without emission control it is estimated that of the hydrocarbon emission, 20 to 25 percent arise from blowby, 60 percent from the exhaust, and the balance from evaporative losses primarily from the fuel tank and to a lesser extent from the carburetor. All other non-hydrocarbon emissions emanate from the exhaust. At least 200 hydrocarbon (HC) compounds have been identified in exhaust. Some such as the olefin compounds react products. These are termed reactive hydrocarbons. Others such as the paraffin are virtually unreactive. Special Developments The Stratified-Charge Engine a modification of the conventional spark-ignition piston engine, the stratified charge engine is designed to reduce emissions without the need for an exhaust-gas recirculation system or catalytic converter. Its key feature is a dual combustion chamber for each cylinder, with a prechamber that receives a rich fuel-air mixture while the main chamber is charged with a very lean mixture. The spark ignites the rich mixture that in turn ignites the lean main mixture. The resulting peak temperature is low enough to inhibit the formation of nitrogen oxides, and the mean temperature is sufficiently high to limit emissions of carbon monoxide and hydrocarbon. Two rather distinct means for accomplishing the stratified charge condition are under consideration :1. A single combustion chamber with a well-controlled rotating air motion. This arrangement is illustrated (Fig.6) by the Texaco Combustion Process (TCP), patented in 1949. 2. A prechamber or two-chamber system. This is illustrated by Fig.7, which shows the general arrangement of the Honda Compound-vortex controlled-combustion (CVCC) system. For both systems, very careful development has proved to be necessary to obtain complete combustion of the fuel under the wide range of speed and load conditions required of an automotive engine.

Revenge for Emily free essay sample

An analysis of the reasons for murder in William Faulkners A Rose for Emily. This paper argues that William Faulkners A Rose for Emily can be interpreted by either looking at Emilys genetic history and family life, or by looking at the society that she lives in. Interpreting according to the above two styles or by combining both styles of reading, the argument is made that Emily is a victim, and that she kills out of revenge. This paper uses and cites two outside critical sources. Watching the evening news and reading the morning newspaper, one is bombarded by tragic, sometimes mysteriously twisted and brutal tales of homicide. More often than not such tales are accompanied by a biography of the murderer themselves which is equally, if not more, tragic and twisted. In many cases, the murderers are actually painted as the first victim in a crime committed as an inevitable consequence of their victimization. We will write a custom essay sample on Revenge for Emily or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page In William Faulkners A Rose for Emily Emily Grierson and her murder of Homer Barron exemplifies the tragedy of one such situation. Is Emily a victim of her own psyche, and its contributing factors? Or is Emily merely a victim of an unstable, judgmental society who pushed her over the edge? Depending on how one reads this story an argument can be made for either interpretation.