The Mayans, The Aztecs, And The Incas Essay Example for Free

The Mayans, The Aztecs, And The Incas EssayFrom 250 A.D. to the late 1500s A.D., three pass on nuances, the Mayans, the Aztecs, and the Incas control lead Central America and South America. Each of them was different but all shared some of the resembling qualities. They all were culturedizations that had a daily life than revolved around religion. Their religions also required a lot of human sacrifices to please the gods. Also, they all invented calendars that were surprisingly complete compared to the calendars today. One of the calendars was less than a minute from being exact. Finally, they all declined for many different reasons but the Spanish conquistadors was one of the most common and deadliest, due to their advanced weapons and the diseases they brought. But even thought they all had mysterious declines, these ancient civilizations of Latin America were very advanced and had many great achievements.The earliest Latin American civilization was the empire of the Maya ns. They controlled most of the Yucatan peninsula and part of southern Mexico. The Mayans were known for their advanced math skills. They invented the number zero and developed a sophisticated counting system of rules the Incas also had an advanced counting system like the Mayans. Mayans communicated through the use of hieroglyphics. They had over 800 symbols that represented things like words, syllables, days, and numbers. The Mayans were also well known for their new vitrine of farming.They called it slash and burn farming in which they cut down all the trees in an area, then they lit the area on fire, so that the ashes from the trees would enrich the acres and make it better to grow in. the decline of the Mayan empire is a mystery still to this day. The most popular theories are that the soil became infertile, so they ran out of food. another(prenominal) theory was that they just got up and left and walked into the jungles. The only other possible theory is because of constan t warfare between the Mayan city-states.After the fall of the Mayan empire, the great civilization of the Aztecs came into power. The Aztecs centered themselves on Lake Texcoco, in the city of Tenochtitlan. The capital city of the Aztecs was built in the center of Lake Texcoco, with volumed causeways, which were large sturdy bridges, connecting the city to the mainland. The Aztecs advanced engine room allowed them to adapt to their environment just as the Mayans and Incas did. The writtenlanguage of the Aztecs was a combination of hieroglyphics and pictorial symbols. Like the Mayans, the Aztecs language was utilize for counting, which was more primitive in Aztec culture, days, records, and communication. The Aztecs expanded their empire through military strength.They conquered the nearby city-states, and forced them to pay tribute or face destruction. But later needed for sacrificial subjects led to less aggressive and less deadly military tactics, causing the strength of the Az tec army to diminish. Around the late 1400s into the 1500s, the power and vastness of the Aztecs began to fade. The once calm and nether control city-states began to rebel, leading to less human sacrifice and less resources being collected. Also, the conquistadors came from Spain, brining along with them deadly diseases like smallpox, and far superior steel weapons, along with a lust for specie. They soon conquered and destroyed the Aztec empire with almost no effort at all.The Incas, down in the Andes Mountains, neer came into contact with the Central American civilizations. They never borrowed any customs or traditions, yet their civilization was fairly similar. They had very advanced engineering skills, which led them to the building of extensive road systems. They also began the idea of terrace farming in which you carve out steps into a hill and farm on the man-made steps. Even though the Incas had no written language, they passed everything down through oral communications. But they did have a complicated counting system in which different sized beads and colored ropes were used to counts things such as military, crops, population, and many other things.The Incas, as did the other Latin empires, had invented a calendar that had 365 days and was kept accurate by looking at the position of the stars, the moon, the planets, and the sun. Due to the complex road system the Incas built, they had to devise a simple messenger system to communicate throughout the empire. Runners would have to travel over twenty-five miles a day to run a message to another runner, then the first runner would have to pass off the message to the turn runner and then the first runner would rest. It works somewhat like a relay race only it isnt a competition. In the late 1500s civil war began to break out between the sons of the emperor after he had died. The empire then split into two halves, but it never became whole again and just slowly began to crumble until it was gone.In c onclusion, these three civilizations were the most sophisticated in all of the Americas at the time. The Mayans were excellent astronomers and mathematicians, the Aztecs were experienced warriors, and the Incas were skilled engineers. Even though all of the empires had different strengths, they all had some similar qualities. They all built stone buildings, with the Mayans and Aztecs and their well-built pyramids, and they all were polytheistic cultures that practiced sacrifices daily. All of these sacrifices led to a large loss in resources both human and natural. The Aztecs alone would sacrifice a quarter of a million people a year. They all used gold and melted it and made figurines to give to the gods. Soon their empires fell apart and the people of the empire just walked away.

Gilgamesh and Odyssey Essay Example for Free

Gilgamesh and Odyssey EssayGilgamesh is an ancient poem that significantly marked its name as in some way organism the first major heroic narrative in the world literature. Fractions of this literature were discovered uniquely carved in tablets even before the Roman, Hebrew and Hellenic civilization appe ard. Gilgamesh depicts a unique and propinquity story of Gilgamesh and his companion Enkidu that transcribed a mixed and moving gist of bonds of friendship, of the pursuit for prominence and of the enduring and lasting attempt to escape death, of which considered to be the common fate of hu world. On the other hand, Odyssey, an epic story by Homer, is concerned on the idyllic events proceeded after a war and mainly on the significant damages of the heroes who survived the war. The main subject of this written epic work in some way focus on the enduring, drawn-out return of one of the heroes named Odysseus of Ithaca, whose fate is to amble in unknown seas for ten eld befor e he returned to his rocky kingdom. This paper will provide detailed and ecumenical comparison between the two main characters from both epics Gilgamesh and Odyssey. pauperization, goals, self-control, assumption, outside influences, behaviors and personal and social human relationships will serve as points of comparison being grasped in this paper. Motivation and Goals Gilgamesh, as exposit in the transcription, was provided with bizarre and astonishing strength, courage, and beauty by his divine and great creator. He is portrayed to be more of a deity than a man. These characteristics of him profoundly surpass wholly circumstances all throughout his journey, a journey that significantly paved the greatest aspiration that probably mankind would have wanted how to escape the general fate of the human race.Simply, Gilgamesh wanted to run away from death and have eternal life. One of the tablets inscribed the sheer dialogue between Gilgamesh and Utanapishtim (The Distant One). Utanapishtim is descriptively the wisest man who ever lived. Gilgameshs search for eternal life led him to ask Utanapishtim the greatest question, how to escape the universal fate of mankind? On a tablet transcribing such meeting, Gilgamesh apparently questions Utanapishtim of how did the latter join the ranks of the gods and find eternal life, though Gilgamesh described him not diametric physically in several(predicate) and yet his eart drained of battle spirit.And as response to the wondering question of Gilgamesh, Utanapishtim told him the story of the flood. Utanapishtim profoundly stated that he was commanded to work out a boat to save bothone from the wrath of a devastating flood made by a god named Enlil, the chief god living on earth to wipe out human race. This story someways illustrates events similar to the biblical script Noahs Ark. The punishment to human race by Enlil gave Utanapishtim the fortune to have eternal life. Gilgameshs greatest achievement though was br inging back to the human race this untold and unknown story.Gilgamesh, by some means, got experience of a plant that can likely grant rebirth to those who eats it, but unfortunately, a serpent stole it from him. With greater wisdom, Gilgamesh returned to Uruk knowing that only the gods are immortal. The goal of seeking immortality is what made both Gilgamesh and Odysseus, from Homers epic Odyssey, distinct and divergent with for each one other. Unlike Gilgamesh, whose goal is to seek and find answers on how to become immortal, Odysseuss goal, on the hand, is merely the fact that he wants to find his way back home after a immense and bloody war.During his navigate towards home, several temptations tested his mental qualities and physical endurance. Circe offered him the Lotus flower that endows forgetfulness of home and family. The greatest temptation however is offered by the goddess fairy-slipper, whom he spent his seven years with immortality. Instead of accepting such prom ising offer of immortality, he somehow denied such and still chooses the human conditions in spite of struggles, difficulties, disappointments and even its foreseeable death.Odysseuss motivational force that drives his willingness to go back home is his wife, Penelope. Self-control Gilgamesh was first described as a king without self-control, rash and violent. People of Uruk, his kingdom, often complained intimately his absence of self-control towards oppressiveness to the Sumerian gods. Due to this aggressiveness, the gods created Enkidu as counterpoise to Gilgamesh. But surprisingly, both Gilgamesh and Enkidu became best of friends they fought together in every battles and wars, and found in each other the true companion they both sought.In an event where both took an adventure to seek universal fame and immortality pictures out the harsh and uncontrollable oppression to the gods overwhelmingly end the curtain to Enkidu. Enkidus death and his continuous and sole journey to seek immortality cause personal transformation. This change and transformation broaden his sensing towards greater acceptance and recognition of reality and mans mortality. On the other hand, Odysseus has extreme sense of self-control. Within the epic story, his remarkable self-control was described and admired.Again, during his adventures on the voyage home, his mental abilities and his physical endurance were tested. Instances occurred that tempted him to descend from his struggle towards home. A Lotus flower is said to suggest forgetfulness of home and family. Circe, goddess of magic, offered a amiable life in the island of Lotus eaters. In the Phaeacia, he once offered the love and marriage of a young princess. Calypso is an immortal goddess whom Odysseus spent his life with for seven years offered the close to significant and most tempting proposal, which probably all of mankind cannot resist.Calypso offered eternal life for Odysseus that will make him immortal. But all of these temptations were single-handedly denied by Odysseus as he preferred more to be mortal and be human amidst varied struggles, disappointments and the predictable end called death. Self-control magnate be a struggle for every man, but if every man has the drive to hold on to their will and embrace limitation, it will never be too late or too impossible to resist and deny any temptations. PrideThe story of Gilgamesh started out as depiction of his arrogance of power. Because of his pyrotechnic capabilities endowed to him by his divine creator, his egotism of power endangered the relationship between mankind and the Summerian gods. To end Gilgameshs arrogance and injustices, gods then created Enkidu. His arrogance and pride concerning his power and unusual capabilities were continuously tested all throughout their journey in quest of rejuvenation of life and immortality.But then again, as mentioned to begin with the previous section, after Enkidus death changed his perception not only towards mans mortality but also the perception of one-self. One of the most significant limitations that Odysseus possesses is his pride which Odysseus had much. Part of the story somehow depicted Odysseuss pride, particularly on the Cyclops island. When Odysseus and his men escaped safely from the island, Odysseus surprisingly brags and boasts close his exploit. Cyclops heard him and tossed huge rocks into the ship and some almost sing the ship.Effect of circumstances surrounding the character There are several away influences that bounds and affects the transformation of the once-known arrogant and violent king of Uruk. Due to the egoistic personality of Gilgamesh, it resulted to the discontentment and complaints from his people in which Summerian God interfered. The effect of these external events somehow paved a new path towards the overall impacts of Gilgameshs journey that led to his transformation from an arrogant king to a more unselfish and wisdom-filled individual.anoth er(prenominal) circumstance that greatly affected the character is the death of his supposed and destined enemy, Enkidu. Enkidu was a god-like mortal created by the gods intended to end Gilgameshs injustices and arrogance. Both somehow became friends and found a true and deep bond of friendship with each other. Death of his friend allowed him to solely seek answers for mankinds immortality, which led him to his wonder that there should no more battle to be fought and needs answers not surpassing violent circumstances.His continuous journey to seek answer guided him to Unatapishtim, the cleric One who could answer Gilgameshs wonderings, and which that this Divine One is blessed with immortality and abundance from the gods. Their conversation drew in new and significant events of the Divine One that gave him unending mortality. This occurrence surprisingly influenced and changed Gilgameshs perception on mans mortality and broadens his acceptance to reality. Odysseuss journey back ho me from the Trojan struggle somehow had endowed circumstances that might affect his own beliefs and characteristics.For example, when tempted by different immortal goddesses, most especially on the offering by Calypso to have everlasting and unending existence, he still grasps tightly to his humanity and instead chose to be human than immortal. His faith and dedication somehow proved that every obstacles and disappointments can be surpassed if he is optimistic enough to exceed and outdo every ounce of it. Behaviors In the beginning of the story, Gilgameshs subservient behavior is steered by his own self-contentment and self-sufficiency.Arrogant, violent, harsh, and no self-control are self-seeking behaviors and characteristics being affixed to the king, in which all these opened doors to discontentment and dissatisfaction from people. Gilgameshs behavior guided him to destruction. This ego-centric trend blinded Gilgamesh from reality that his conscious tried to make him see. For a n instance, Gilgamesh tried to strike down on Ishtar during their second adventure to Cedar Forest with Enkidu. Ishtar cannot handle Gilgameshs harsh rejection and provoked to send the Bull of Heaven against the people of Uruk.Although they succeeded, it brought terrible damage to his kingdom and brought about the painful death of Enkidu. Unlike Gilgamesh, who is depicted as ego-centric individual, Odysseus has the contrast of this characteristic. Odysseus is optimistic and altruistic as he struggles not only for his own survival during the war, but also for his shipmates personal survival. Odysseus is described having versatility which any way compliments his physical strength and courage in battle, skills he showed during the war at Troy.These behaviors somehow resulted from his eagerness to return home to his wife and from his sedulousness to preserve and finish the heroic reputation and dignity that he won in war at Troy. The same scene that illustrated Odysseus pride also dep icts his sustainment and being concerned to his crevice shipmates. After Cyclops threw boulders to the ship, Odysseus hastily gave his identity to Cyclops and the latter called Poseidon, his father, to punish Odysseus who brought harm to him. That incident hurt Odysseus more than losing his fellow men. This showed Odysseuss heed towards his fellow shipmen.Personal and Social Relationships The Gilgamesh poem depicted not only ancient Mesopotamian myths and legends, but also endowed diverse and complex relationships and dealings between people involved in the epic story, particularly the main character, Gilgamesh. Gilgameshs relationship towards his people as a king is somehow in deep and shaky condition. There have been misunderstandings and lack of sense of unity between the king and its people that hindering a kingdom to grow due to Gilgameshs disturbing and arrogant means of ruling Uruk. Another unstable relationship is with Gilgamesh and the Summerian gods.Gilgamesh tends to o ppress the gods which led to the creation of Enkidu. Although Enkidu was created as a counterweight of Gilgamesh, unpredictably, both became friends. Relationship between the king and the supposed enemy is probably the most light and happy relationship made by Gilgamesh. They think of each other as brothers and a true companion in which their common journey indeed deepened their brotherly bond and friendship. There are also different relationship built all throughout the story between Odysseus and other characters in the epic.Again, he built a strong and deep bond and comradery with his fellow men. He even risked himself just to keep other from falling in the hands of Cyclops. Odysseus somehow has heart of gold for those who treasure him and appreciate him from his doings. His relationship with his wife, Penelope, also is as strong and sturdy as a diamond which no one can break even through rough and long times of being away from each other. To show his commitment and love to his w ife, he even tricks his wifes suitors and disguised himself as beggar.

Child Trafficking In Nigeria Social Work Essay

Child Trafficking In Nigeria Social Work EssayHuman trafficking in Nigeria has been one of the greatest problem in Nigerian history. Human trafficking can be traced to the period colonialism when human beings argon been traded for mere commodities to the Europeans, to help them in their plantations in their own country. Due to the abolishment of slave trade in Nigeria by 1885-1950, the act of human trafficking was reduced and some few years later they started babe trafficking since the peasantren ar more vulnerable. Child trafficking is a form of human trafficking that involves the transportation, harbouring, receiving ,recruitment of nestlingren in the purpose of exploitation.The issue of kid domestic labour is very complex and problematic. national tiddler labourers atomic number 18 among the most invisible child labourers. The number of children exploited in private households is unknown because of the hidden nature of the work. Many of these children are girls and in many countries domestic service is seen as the only employment option a girl might behave. Children exploited in domestic service are paid little or nonhing, are malnourished, are very vulnerable to further abuse and exploitation, and do not go to school. However, because child domestic workers are employed within an informal family environment, they cannot be integrated as a professional group within conventional working systems because such integration would reckon an acceptance of the idea of child domestic labour. At the same time, without legal initiatives, it is difficult to combat child domestic labour. Furthermore, the terms, norms and standards to regulate the employment of children are lacking because children work in a largely invisible domain outside law and the public sphere and their domestic labour cannot be integrated on a lower floor normal labour laws. Although the final goal of all laws should be the prevention and elimination of child domestic labour, it is ack nowledged right at the outset that this is a long term goal. In the interim, there is a need to accept that children do, and will continue, to work until effective alternatives make it unnecessary for them to work. In the meantime, the best rice beer of the child principle together with the notion of the child as a rights holder should guide any lawmaking on child domestic work. police and policy reform can play a powerful constitutive and transformative role in improving and changing the lives of both the girl child and anthropoid child domestic worker however, in envisioning workplace and domestic arrangements it is important to see that sex stereotypes are not reinforced. Just as some(prenominal) as law has the profound power to prevent and regulate domestic labour, it has the power to reinforce it by creating loopholes through which employers can continue to hire child domestic workers. Laws can a solid deal spark social change only if they are translated into action. In drafting new laws or revising existing laws, child domestic labour should be seen in the context of historic sex discrimination. There is an apparent tension when laws and policies are blind to the differences between the girl child domestic worker and the male child domestic worker such as the girl childs weak bargaining position and low status, which increases her vulnerability to obsession by her family and employer.Child trafficking in Nigeria is something the organization has not really put enough effort to ensure that child trafficking is reduced or eradicated this is due to the put across (corruption) of the whole presidential term system because most of the child traffickers are top political sympathies officials and this makes it very difficult to investigate any problem that has to do with child trafficking. According to a research carried out by United nation children fund (unicef) say the aver period age of children been trafficked in Nigeria is around 15years but t he age varies, especially with girls and also it says 60-80% of girls in the sex trade outside the country are in Italy (over 700 in Italy while Belgium and Holland is experiencing an upsurge in the number of Nigerian girls. On the average About 10 children pass Nigerian borders daily originating from fostering and extended family system. Children that are been trafficked has so many reasons which include domestic help, prostitution these are especially for girls while boys are used as scavengers, car washing, bus conducting, drug peddling and farming.Child trafficking has so many effects on both the child and the country. Trafficking of migrant children has unquestionably affected individual children and their communities in various immediate and long term ways. It sometimes endangers the childrens lives. The obvious impacts of child trafficking often mentioned is on deteriorating their education, physical and mental development. Moreover, the trafficked migrant children are disem powered in many ways. They are in the foreign country with foreign customs and foreign language. They are transported and sold or deceived as bonded labour, treated like property, and work under slavery-like conditions. Whenever they feel depressed, or suffering, or face difficulties, or are tortured, commonly they have no one they can turn to as they tend to live in isolated theaters. Even if they have a chance to seek help, they often do not know where to go or what to do or whom to ask because they are illegal migrants and are afraid of police. In some circumstances, they whitethorn encounter racism from the police, authorities, and general people among whom may be their own employers. A major result of child trafficking can be loss of lives, increase prevalence of STDs (sexually transmitted diseases) including HIV/AIDS, increase in violence and crime rate, increased school drop-out, impaired child development, poor national image and coarse deportation of Nigerians especially girls. And also, There are diverse reasons why many Nigerian children are vulnerable to trafficking, including widespread poverty, large family size, rapid urbanization with deteriorating public services, low literacy take aims and high school-drop out ratesThe demand for cheap commercial sex workers in countries of destination strongly contributes to the growth of this phenomenon and the success of this criminal intercommunicate.Parents with a large family, often overburdened with the care of too many children, are prone to the traffickers deceit in well-favoured away some of their children to city residents or even strangers promising a better life for them.Traffickers exploit the trust of people rooted in a widespread, culturally accepted common drill in West Africa of placement and fostering as part of the extended familysafety net. In some instances, desperately poor and uninformed parents willingly co-operate with the traffickers, giving away their children in exchange for a small fee. In thehands of unscrupulous guardians, these children are increasingly trafficked and exploited for money.But All hope is not lost as every problem has a solution. The government can still curb this evil practice in order to save children and the good name of the country. Firstly, government should provide free education in every government owned school in the country from the nursery to the secondary level so that parents will have no excuse of giving out their children to strangers in the pretext of taking them to learn new sill in new environment.Secondly, government should pay workers salaries at the end of each month because they have personal bills to foot children to cater for and they depend solely on their salaries.Thirdly, the parliamentary arm of the government should make and amend law that all Nigerian families should not have more than 3 children and any found to go against the law would be punish because one of the causes of child trafficking in Nigeria is the inability of parents to cater for so many children.Also, government should make laws for children against child abuse and intimidation which should be strictly adhered to. experience but not the least, government should come to an agreement with leaders of other countries that any Nigerian child suspected to be abused or trafficked should be rescued and the trafficker, punished.In an effort aimed at battling child trafficking within Nigeria and the sub-region, Nigeria and the government of Benin Republic have signed a memorandum of understanding to co-operate in the area of prevention of child trafficking as well as the repatriation of offenders to countries of origin for prosecution. administrator Secretary of National Agency for the Prohibition of Traffic in Persons and Other connect Matters(NAPTIP), Mrs. Carol Ndaguba disclosed this at a one-day workshop on Anti Child Trafficking Network Project in Nigeria held at the UN House Abuja.According to her, Nigeria and the gover nment of Italy, United Kingdom and Spain also have understandings on joint initiative on modalities for prevention of child trafficking and slavery, adding that the Italian government as well as UNICEF have been providing huge financial and capacity building support to the agency in carrying out its task.On the issue of house-help or domestic servants in the country, NAPTIP Executive Secretary regretted that the phenomenon had been exploited by traffickers to batter, sexually or emotionally traumatize victims, adding that the so called syndrome must now come to an end.She identified the challenges faced by the network project to include expansion of the network from 22 states to 36, sustaining awareness campaign at the state and community levels, and capacity building of the state working groups.In her remark, Deputy Country Representative of UNICEF, Barbara Reynold said that although the anti-trafficking agency was already doing a lot to put an end to the menace of human traffickin g, more needs to be done in the area of conscientisation and increased awareness by a broader section of society.

Single Stage to Orbit (SSTO) Propulsion System

Single Stage to Orbit (SSTO) actuation SystemThis paper discusses the relevant selection criteria for a single stage to orbit (SSTO) propulsion governing body and and so reviews the characteristics of the typical railway locomotive signs proposed for this role against these criteria. The engine types considered include Hydrogen/Oxygen (H2/O2) uprises, Sc beatjets, Turbojets, Turbo go ups and Liquid logical argument Cycle locomotives. In the authors opinion no(prenominal) of the supra engines be able to meet all told the necessary criteria for an SSTO propulsion dodging simultaneously. muchover by selecting appropriate features from each it is affirmable to synthesise a impertinent class of engines which are specifically optimised for the SSTO role. The resulting engines employ precooling of the send outstream and a postgraduate internal crush balance to enable a relatively conventional high up coerce rocket combustion chamber to be utilised in two pushoverbre athing and rocket paths. This results in a significant mass saving with quickness emoluments which by careful design of the oscillation thermodynamics enables the full potential of airbreathing to be realised. The SABRE engine which powers the SKYLON launch vehicle is an example of one of these so called cool hybrid airbreathing rocket engines and the judgmentual reasoning which leads to its main(prenominal) design parameters are described in the paper.Keywords Reusable launchers, SABRE, SKYLON, SSTO1.IntroductionSeveral organisations world- huge are studying the technical and technical feasibleness of reusable SSTO launchers. This new class of vehicles appear to offer the tantalising prospect of greatly rock-bottom recurring bells and incr sticking out(p) reliability compared to exist expendable vehicles. However achieving this break done is a difficult task since the attainment of orbital velocity in a re-entry capable single stage demands bonzer propulsive motion .Most studies to date bewilder focused on high press henry/ atomic number 8 (H2/O2) rocket engines for the primary propulsion of such vehicles. However it is the authors opinion that despite recent advances in materials technology such an approach is non destined to succeed, due to the relatively gloomy specific impulse of this type of propulsion. Airbreathing engines offer a possible r protrudee forward with their intrinsically higher specific impulse. However their first gouge/ cant ratio, limited Mach issuing score and high dynamic jam trajectory name in the past cancelled any theoretical advantage.By design review of the relevant characteristics of both rockets and airbreathing engines this paper sets out the rationale for the selection of deeply precooled hybrid airbreathing rocket engines for the main propulsion agreement of SSTO launchers as exemplified by the SKYLON vehicle 1.2. Propulsion CandidatesThis paper volition solely consider those engine types which wo uld result in politically and environmentally acceptable vehicles. Therefore engines employing nuclear answers (eg onboard fission reactors or immaterial nuclear pulse) and chemical engines with toxic exhausts (eg fluorine/oxygen) will be excluded.The candidate engines can be split into two broad groups, namely clarified rockets and engines with an airbreathing persona. Since none of the airbreathers are capable of accelerating an SSTO vehicle all the way to orbital velocity, a practical vehicle will always have an onboard rocket engine to pad the ascent. Therefore the use of airbreathing has always been proposed within the context of improving the specific impulse of pure rocket propulsion during the initial first gearer Mach portion of the trajectory.Airbreathing engines have a much junior-gradeer sack/ weight ratio than rocket engines (10%) which tends to outgrowth the advantage of reduced discharge custom. Therefore vehicles with airbreathing engines invariably have w ings and employ a lifting trajectory in order to reduce the installed thrust requirement and hence the airbreathing engine mass penalty. The cabal of wings and airbreathing engines hence demands a low flat trajectory (compared to a ballistic rocket trajectory) in order to maximise the installed performance (i.e. (thrust-drag)/fuel head for the hills). This high dynamic pressure trajectory gives rise to one of the drawbacks of an airbreathing approach since the airframe light uping and loading are increased during the ascent which ultimately reflects in increased structure mass. However the commanding level of mass growth depends on the relative moroseness of the ascent as compared with reentry which in turn is mostly dependant on the type of airbreathing engine selected. An additional drawback to the low trajectory is increased drag passinges particularly since the vehicle loiters longer in the lower atmosphere due to the lower acceleration, offset to some(prenominal) extent by the much reduced gravity loss during the rocket ply ascent.Importantly however, the addition of a set of wings brings more than just performance advantages to airbreathing vehicles. They also give considerably increased abort capability since a properly configured vehicle can remain in stable flight with up to half of its propulsion systems shutdown. Also during reentry the presence of wings reduces the ballistic coefficient thereby reducing the heating and hence thermal breastplate system mass, whilst simultaneously improving the vehicle lift/drag ratio permitting greater crossrange.The suitability of the following engines to the SSTO launcher role will be discussed since these are representative of the main types presently down the stairs study within various organisations world-wideLiquid Hydrogen/Oxygen rocketsRamjets and ScramjetsTurbojets/Turborockets and variantsLiquid Air Cycle Engines (LACE) and Air accumulation Engines (ACE)Precooled hybrid airbreathing rocket engi nes(RB545/SABRE)3.Selection CriteriaThe selection of an optimum propulsion system involves an assessment of a number of interdependant factors which are listed below. The relative importance of these factors depends on the severity of the mission and the vehicle characteristics.Engine performanceUseable Mach number and altitude range.Installed specific impulse.Installed thrust/weight.Performance sensitivity to component level efficiencies.Engine/Airframe consolidationEffect on airframe layout (Cg/Cp pitch trim structural efficiency).Effect of required engine trajectory (Q and heating) on airframe technology/materials.Technology levelMaterials/structures/aerothermodynamic and manufacturing technology.Development costEngine scale and technology level.Complexity and power demand of kingdom test facilities.Necessity of an X unconditional research project to precede the main development program.4.Hydrogen/Oxygen Rocket EnginesHydrogen/oxygen rocket engines achieve a very high thrust/ weight ratio (60-80) but relatively low specific impulse (450-475 secs in vacuum) compared with conventional airbreathing engines. Due to the relatively with child(p) V involve to reach low earth orbit (approx 9 km/s including gravity and drag losses) in relation to the engine exhaust velocity, SSTO rocket vehicles are characterised by very high mass ratios and low warhead fractions.The H2/O2 propellant combination is invariably chosen for SSTO rockets due to its higher performance than other alternatives despite the structural penalties of employing a very low minginess cryogenic fuel. In order to maximise the specific impulse, high field of view ratio nozzles are required which inevitably leads to a high chamber pressure cycle in order to give a compact installation and reduce back pressure losses at low altitude. The need to belittle back pressure losses normally results in the selection of some form of altitude compensating nozzle since conventional bell nozzles have high difference and overexpansion losses when running in a separated condition.The high thrust/weight and low specific impulse of H2/O2 rocket engines spares vertical takeoff flightless vehicles since the wing mass and drag penalty of a lifting trajectory results in a smaller lode than a steep ballistic climb out of the atmosphere. The ascent trajectory is therefore extremely benign (in terms of dynamic pressure and heating) with vehicle material selection determined by re-entry. Relative to airbreathing vehicles a pure rocket vehicle has a higher density (gross take off weight/ raft) due to the reduced hydrogen consumption which has a fortunate effect on the tankage and thermal protection system mass.In their favour rocket engines represent broadly known (current) technology, are ground testable in mere(a) facilities, functional throughout the whole Mach number range and physically very compact resulting in good engine/airframe integration. Abort capability for an SSTO rocket vehic le would be achieved by arranging a high takeoff thrust/weight ratio (eg 1.5) and a cock-a-hoop number of engines (eg 10) to permit shutdown of at least two whilst retaining overall vehicle control. From an operational standpoint SSTO rockets will be relatively noisy since the high takeoff mass and thrust/weight ratio results in an installed thrust level up to 10 times higher than a well designed airbreather.Reentry should be relatively straightforward providing the vehicle reenters base first with active cooling of the engine nozzles and the vehicle base. However the maximum lift/drag ratio in this attitude is relatively low (approx 0.25) pass the maximum achievable crossrange to well-nigh 250 km. Having reached a low altitude some of the main engines would be restarted to control the subsonic descent before ultimately effecting a tailfirst landing on legs. Low crossrange is not a particular problem providing the vehicle operator has adequate time to wait for the orbital plane t o cross the landing site. However in the case of a military or commercial operator this could pose a serious operational barricade and is consequently considered to be an undesirable characteristic for a new launch vehicle.In an attempt to increase the crossrange capability some designs attempt nosefirst re-entry of a numb cone shaped vehicle or alternatively a blended wing/body configuration. This approach potentially increases the lift/drag ratio by reducing the fuselage wave drag and/or increasing the aerodynamic lift generation. However the drawback to this approach is that the nosefirst attitude is aerodynamically unstable since the aft mounted engine software package pulls the empty center of gravity a considerable distance behind the hypersonic center of pressure. The resulting pitching moment is difficult to trim without adding nose ballast or large control surfaces projecting from the vehicle base. It is expected that the additional mass of these components is likely to erode the small payload capability of this engine/vehicle combination to the point where it is no longer feasible.Recent advances in materials technology (eg fibre reinforced plastics and ceramics) have made a big impact on the feasibility of these vehicles. However the payload fraction is still very small at around 1-2% for an Equatorial low Earth orbit falling to as low as 0.25% for a Polar orbit. The low payload fraction is generally perceived to be the main disadvantage of this engine/vehicle combination and has historically embarrassed the development of such vehicles, since it is felt that a small degree of optimism in the preliminary mass estimates may be concealing the fact that the real payload fraction is negative.One possible route forward to increasing the average specific impulse of rocket vehicles is to employ the atmosphere for both oxidiser and reaction mass for part of the ascent. This is an old idea dating back to the 1950s and revitalised by the emergence of the BAe/Rolls Royce HOTOL project in the 1980s 2. The following sections will review the main airbreathing engine candidates and trace the design background of precooled hybrid airbreathing rockets.5.Ramjet and Scramjet EnginesA ramjet engine is from a thermodynamic viewpoint a very simple device consisting of an intake, combustion and nozzle system in which the cycle pressure rise is achieved purely by ram compression. Consequently a separate propulsion system is needed to accelerate the vehicle to speeds at which the ramjet can takeover (Mach 1-2). A conventional hydrogen fuelled ramjet with a subsonic combustor is capable of operating up to around Mach 5-6 at which point the limiting effects of dissociation reduce the effective heat addition to the flow of air resulting in a rapid loss in nett thrust. The idea behind the scramjet engine is to avoid the dissociation limit by only part slowing the airstream through the intake system (thereby reducing the static temperature rise) and h ence permitting greater useful heat addition in the now ultrasonic combustor. By this means scramjet engines offer the tantalising prospect of achieving a high specific impulse up to very high Mach numbers. The consequent decrease in the rocket powered V would translate into a large saving in the mass of liquid oxygen required and hence possibly a reduction in launch mass.Although the scramjet is theoretically capable of generating positive nett thrust to a significant fraction of orbital velocity it is unworkable at low supersonic speeds. Therefore it is generally proposed that the internal geometry be reconfigured to function as a conventional ramjet to Mach 5 followed by transition to scramjet mode. A further reduction of the useful speed range of the scramjet results from consideration of the nett vehicle specific impulse ((thrust-drag)/fuel flow) in scramjet mode as compared with rocket mode. This tradeoff shows that it is more effective to shut the scramjet down at Mach 12-15 and continue the remainder of the ascent on pure rocket power. Therefore a scramjet powered launcher would have four main propulsion modes a low speed accelerator mode to ramjet followed by scramjet and finally rocket mode. The proposed low speed propulsor is a lot a ducted ejector rocket system employing the scramjet injector struts as both ejector nozzles to entrain air at low speeds and later as the rocket combustion chambers for the final ascent.Whilst the scramjet engine is thermodynamically simple in conception, in engineering practice it is the most complex and technically demanding of all the engine concepts discussed in this paper. To make matters worse many studies including the recent ESA Winged Launcher Concept study have failed to show a positive payload for a scramjet powered SSTO since the fundamental propulsive characteristics of scramjets are measlyly suited to the launcher role. The low specific thrust and high specific impulse of scramjets tends to favour a crui se vehicle application flying at repair Mach number over long distances, especially since this would enable the elimination of most of the multivariate geometry.Scramjet engines have a relatively low specific thrust (nett thrust/airflow) due to the stamp down combustor temperature rise and pressure ratio, and therefore a very large air mass flow is required to give adequate vehicle thrust/weight ratio. However at constant freestream dynamic head the captured air mass flow reduces for a given intake area as speed rises above Mach 1. Consequently the full vehicle frontal area is needed to serve as an intake at scramjet speeds and similarly the exhaust flow has to be re-expanded back into the original streamtube in order to achieve a conceivable exhaust velocity. However employing the vehicle forebody and aftbody as part of the propulsion system has many disadvantagesThe forebody boundary shape (up to 40% of the intake flow) must be carried through the entire shock system with co nsequent likelihood of upsetting the intake flow stability. The conventional solution of bleeding the boundary layer off would be unacceptable due to the prohibitive momentum drag penalty.The vehicle undersurface must be flat in order to provide a middling uniform flowfield for the engine installation. The flattened vehicle cross section is poorly suited to pressurised tankage and has a higher surface area/volume than a pear-shaped cross section with knock-on penalties in aeroshell, insulation and structure mass.Since the engine and airframe are physically inseparable little freedom is available to the designer to control the vehicle pitch balance. The single sided intake and nozzle systems positioned underneath the vehicle generate both lift and pitching moments. Since it is necessary to optimise the intake and nozzle system geometry to maximise the engine performance it is extremely unlikely that the vehicle will be pitch balanced over the entire Mach number range. Further it is not clear whether adequate CG movement to trim the vehicle could be achieved by active propellant transfer.Clustering the engines into a compact package underneath the vehicle results in a highly interdependant flowfield. An unexpected failure in one engine with a consequent loss of internal flow is likely to unstart the entire engine installation precipitating a violent change in vehicle pitching moment.In order to focus the intake shock system and generate the correct duct flow areas over the whole Mach range, variable geometry intake/combustor and nozzle surfaces are required. The large variation in flow departure shape forces the adoption of a rectangular engine cross section with flat moving ramps thereby incurring a severe penalty in the pressure vessel mass. Also to maximise the installed engine performance requires a high dynamic pressure trajectory which in combination with the high Mach number imposes severe heating rates on the airframe. Active cooling of significant p ortions of the airframe will be necessary with further penalties in mass and complexity.Further drawbacks to the scramjet concept are evident in many areas. The nett thrust of a scramjet engine is very sensitive to the intake, combustion and nozzle efficiencies due to the exceptionally poor work ratio of the cycle. Since the exhaust velocity is only slightly greater than the incoming freestream velocity a small reduction in pressure retrieval or combustion efficiency is likely to convert a small nett thrust into a small nett drag. This situation might be tolerable if the theoretical methods (CFD codes) and engineering knowledge were on a very solid footing with ample correlation of theory with experiment. However the reality is that the component efficiencies are dependant on the detailed physics of poorly understood areas like flow turbulence, shock wave/boundary layer interactions and boundary layer transition. To exacerbate this deficiency in the underlying physics existing groun d test facilities are unable to replicate the flowfield at physically representative sizes, forcing the adoption of expensive flight research vehicles to acquire the necessary data.Scramjet development could only proceed after a lengthy technology program and even then would probably be a risky and expensive project. In 1993 Reaction Engines estimated that a 130 tonne scramjet vehicle development program would cost $25B (at fixed prices) assuming that the program proceeded according to plan. This program would have included two X planes, one devoted to the subsonic intervention and low supersonic political science and the other an air dropped scramjet research vehicle to explore the Mach 5-15 regime.6.Turbojets, Turborockets andVariantsIn this section are grouped those engines that employ turbocompressors to compress the airflow but without the aid of precoolers. The advantage of cycles that employ onboard work transfer to the airflow is that they are capable of operation from sea level static conditions. This has important performance advantages over engines employing solely ram compression and additionally enables a cheaper development program since the mechanical reliability can be acquired in relatively inexpensive open air ground test facilities.6.1 TurbojetsTurbojets (Fig. 1) exhibit a very rapid thrust decay above active Mach 3 due to the effects of the rising compressor inlet temperature forcing a reduction in both flow and pressure ratio. Compressors must be operated within a stable part of their characteristic bounded by the mint and choke limits. In addition structural considerations impose an upper outlet temperature and spool speed limit. As inlet temperature rises (whilst operating at constant WT/P and N/T) the spool speed and/or outlet temperature limit is rapidly approached. Either way it is necessary to throttle the engine by moving down the running line, in the process reducing both flow and pressure ratio. The consequent reduction in nozz le pressure ratio and mass flow results in a rapid loss in nett thrust.However at Mach 3 the vehicle has received an insufficient get ahead to make up for the mass penalty of the airbreathing engine. Therefore all these cycles tend to be proposed in conjunction with a subsonic combustion ramjet mode to higher Mach numbers. The turbojet would be isolated from the hot airflow in ramjet mode by blocker doors which allow the airstream to flow around the core engine with small pressure loss. The ramjet mode provides reasonable specific thrust to around Mach 6-7 at which point transition to rocket propulsion is effected.Despite the ramjet extension to the Mach number range the performance of these systems is poor due mainly to their low thrust/weight ratio. An uninstalled turbojet has a thrust/weight ratio of around 10. However this falls to 5 or less when the intake and nozzle systems are added which compares badly with a H2/O2 rocket of 60+.6.2 TurborocketThe turborocket (Fig. 2) cycle s represent an attempt to improve on the low thrust/weight of the turbojet and to increase the useful Mach number range. The pure turborocket consists of a low pressure ratio fan driven by an entirely separate turbine employing H2/O2 combustion products. Due to the separate turbine working fluid the matching problems of the turbojet are eased since the compressor can in principle be operated anywhere on its characteristic. By manufacturing the compressor components in a suitable high temperature material (such as reinforced ceramic) it is possible to eliminate the ramjet bypass duct and operate the engine to Mach 5-6 whilst staying within outlet temperature and spool speed limits. In practice this involves operating at reduced nondimensional speed N/T and hence pressure ratio. Consequently to avoid choking the compressor outlet guide vanes a low pressure ratio compressor is selected (often only 2 stages) which permits operation over a wider flow range. The turborocket is considerabl y lighter than a turbojet. However the low cycle pressure ratio reduces the specific thrust at low Mach numbers and in conjunction with the preburner liquid oxygen flow results in a poor specific impulse compared to the turbojet.6.3 Expander Cycle TurborocketThis cycle is a variant of the turborocket whereby the turbine working fluid is replaced by high pressure regeneratively heated hydrogen warmed in a heat exchanger rigid in the exhaust duct (Fig. 3). Due to heat exchanger metal temperature limitations the combustion process is normally split into two stages (upstream and downstream of the ma-LHLH LOx/LH2Fig. 1 Turbo-ramjet Engine (with integrated rocket engine).LOx/LH2LH2 LOx/LH2Fig. 2 Turborocket.LH2LOx/LH2Fig. 3 Turbo-expander engine.trix) and the turbine entry temperature is quite low at around 950K. This variant exhibits a moderate improvement in specific impulse compared with the pure turborocket due to the elimination of the liquid oxygen flow. However this is achieved at the expense of additional pressure loss in the air ducting and the mass penalty of the heat exchanger.Unfortunately none of the above engines exhibit any performance improvement over a pure rocket approach to the SSTO launcher problem, despite the wide variations in core engine cycle and machinery. This is for the simple reason that the core engine masses are swamped by the much larger masses of the intake and nozzle systems which tend to outweigh the advantage of increased specific impulse.Due to the relatively low pressure ratio ramjet modes of these engines, it is essential to provide an efficient high pressure recovery variable geometry intake and a variable geometry exhaust nozzle. The need for high pressure recovery forces the adoption of 2 dimensional geometry for the intake system due to the requirement to focus multiple oblique shockwaves over a wide mach number range. This results in a very serious mass penalty due to the inefficient pressure vessel cross section and the physically large and complicated moving ramp assembly with its high actuation loads. Similarly the exhaust nozzle geometry must be capable of a wide area ratio variation in order to cope with the widely differing flow conditions (WT/P and pressure ratio) between transonic and high Mach number flight. A further complication emerges due to the requirement to integrate the rocket engine needed for the later ascent into the airbreathing engine nozzle. This avoids the prohibitive base drag penalty that would result from a separate dead nozzle system as the vehicle attempted to accelerate through transonic.7. Liquid Air Cycle Engines (LACE) and Air Collection Engines (ACE)Liquid Air Cycle Engines were first proposed by Marquardt in the early 1960s. The simple LACE engine exploits the low temperature and high specific heat of liquid hydrogen in order to liquify the captured airstream in a specially designed condenser (Fig. 4). Following liquifaction the air is relatively considerably pump ed up to such high pressures that it can be fed into a conventional rocket combustion chamber. The main advantage of this approach is that the airbreathing and rocket propulsion systems can be combined with only a single nozzle required for both modes. This results in a mass saving and a compact installation with efficient base area utilisation. Also the engine is in principle capable of operation from sea level static conditions up to perhaps Mach 6-7.LH2 LO2Liquid Air Turbopump Fig. 4 Liquid Air Cycle Engine (LACE).The main disadvantage of the LACE engine however is that the fuel consumption is very high (compared to other airbreathing engines) with a specific impulse of only about 800 secs. Condensing the airflow necessitates the removal of the latent heat of vaporisation under isothermal conditions. However the hydrogen coolant is in a supercritical state following compression in the turbopump and absorbs the heat load with an accompanying increase in temperature. Consequently a temperature pinch point occurs within the condenser at around 80K and can only be controlled by increasing the hydrogen flow to several times stoichiometric. The air pressure within the condenser affects the latent heat of vaporisation and the liquifaction temperature and consequently has a strong effect on the fuel/air ratio. However at sea level static conditions of around 1 bar the minimum fuel/air ratio required is about 0.35 (ie 12 times greater than the stoichiometric ratio of 0.029) assuming that the hydrogen had been compressed to 200 bar. Increasing the air pressure or reducing the hydrogen pump delivery pressure (and temperature) could reduce the fuel/ air ratio to perhaps 0.2 but nevertheless the fuel flow remains very high. At high Mach numbers the fuel flow may need to be increased further, due to heat exchanger metal temperature limitations (exacerbated by hydrogen embrittlement limiting the choice of tube materials). To reduce the fuel flow it is sometimes proposed t o employ slush hydrogen and recirculate a portion of the coolant flow back into the tankage. However the handling of slush hydrogen poses difficult technical and operational problems.From a technology standpoint the main challenges of the simple LACE engine are the need to prevent clogging of the condenser by frozen carbon dioxide, argon and water vapour. Also the ability of the condenser to cope with a changing g transmitter and of designing a scavenge pump to operate with a very low NPSH inlet. Nevertheless performance studies of SSTOs equipped with LACE engines have shown no performance gains due to the inadequate specific impulse in airbreathing mode despite the reasonable thrust/weight ratio and Mach number capability.The Air Collection Engine (ACE) is a more complex variant of the LACE engine in which a liquid oxygen separator is incorporated after the air liquifier. The tendency is to takeoff with the main liquid oxygen tanks empty and fill them during the airbreathing ascen t thereby possibly reducing the undercarriage mass and installed thrust level. The ACE principal is often proposed for parallel operation with a ramjet main propulsion system. In this variant the hydrogen fuel flow would condense a quantity of air from which the oxygen would be separated before entering the ramjet combustion chamber at a near stoichiometric mixture ratio. The liquid newton from the separator could perform various cooling duties before being fed back into the ramjet airflow to recover the momentum drag.The oxygen separator would be a complex and heavy item since the physical properties of liquid oxygen and nitrogen are very similar. However setting aside the engineering details, the prefatorial thermodynamics of the ACE principal are wholly unsuited to an SSTO launcher. Since a fuel/air mixture ratio of approximately 0.2 is needed to liquify the air and since oxygen is 23.1% of the airflow it is apparent that a roughly equal mass of hydrogen is required to liquify a given mass of oxygen. Therefore there is no saving in the takeoff propellant loading and in reality a severe structure mass penalty due to the increased fuselage volume needed to contain the low density liquid hydrogen.8. Precooled Hybrid AirbreathingRocket EnginesThis last class of engines is specifically formulated for the SSTO propulsion role and combines some of the best features of the previous types whilst simultaneously overcoming their faults. The first engine of this type was the RB545 powerpla

The Nature of Construction Problems: Past and Present

The Nature of Construction Problems Past and PresentABSTRACT This paper aims at deriving a across-the-board understanding pertaining to the different construction difficulties that pick out been faced in the past and be being faced at one time in the present also. It provides a intense analysis of why the problems were faced, the nature of the problems and how they were dealt with.It has been a long time since the first inception of architectural ideas that had crept into our ancestors minds. Right from the Stone Age, man has actually been into this act of constructing hinder for making his life easy. At the very juncture of the Metal Age, he got a further boost with the advent of new materials and construction techniques. Furthermore, came the time when computer computer architecture was at its peak. Everywhere in the world there was zeal to construct structures that non only made life comfortable for man, but also soothed his eyes. The classic orders of the Greeks packed the punch of serving as better structural members along with being a visual treat. The Romans had been articulate in constructing an efficient system of piss supply in the nisus of a series of arches together being called as aquaducts. It still stands as an example people look up to anatomy urban spaces. Egyptians were no less. They were meticulously constructing pyramids and mortuary tombs that were way beyond the human scale. They had inclinationed the first forms of conveyor systems in building construction. Similarly, India saw the construction of a lot of architectural wonders. Right from the construction of the monolithic stone structures of the Ajanta-Ellora caves and the synagogues of Mahabalipuram to the Islamic structures of Taj Mahal and the Humayuns tomb it had been a marvellous leap in the form of architectural progress. Finally came the times of contr everyplacesies about architecture when Gustav Eiffel proposed the construction of an all metal structure now calle d the Eiffel tower. There was a lot of noise about the particular that how it would finally look when it was constructed in Paris. Many people said that it might turn out to be a scar on the face of the city. But, now fortunately it is known as the first thing that helps us identify the city of Paris. There behave also been controversies about Zaha Hadids designs. She is one of the pioneer architects as far as the use of fluidic forms is concerned. Her designs have al nearly always been at the helm of criticism by the senior architects of her times. But, she has been articulate in implementation her own designs. Similarly, in the recent times Frank O Gehry had faced a lot of challenges in bringing up his work called Bilbao museum. He has been criticised c are hell up to the level of being called the mad architect. Now as we come up to the fact of such progress in the field of construction, shadow we deny that there have been no difficulties in the construction of these age old structures? No will be the answer.As we go back to the times when the monolithic stone structures of the Kailasa temple was constructed, we get to know that no good technology was available at that time. However, they have managed to actually make it possible to form a massive temple out of a single rock. Imagine that how the person who started the construction, actually just utilize a chisel and a pounding to build such a huge temple. It is said that he started from the top and kept on chiselling till the bottom. It is evident that this wonderful construction must have taken a long time to come up. But, it has not been constructed by a single sculptor. Imagine the difficulty in passing on the aforementioned(prenominal) knowledge about the structure to so many artisans over the ages. There might have been several changes made to this temple structure during the construction. This must have made it even more difficult for the sculptors. Now raises the doubt of managing the waste that was generated in this process. How were all the cut out stones used? Yes, they were used to make roadstead and for pety constructions. But wasnt it really difficult to manage these heavy masses? Yes, it must have been tedious. A similar structure had come up previously. The Konark temple in Bhubaneshwar, Orissa had a huge contribution in raising the architectural taste of the people of the country. In this construction, they used the method of constructing sand ramps as it was being constructed towards the top end. This had actually ensured that the structure didnt get decayed during the construction process. However, this structure had made use of a huge pole at the center field in the form of a magnet that gave the massive stone structure all its strength. This had been acquired by the British during their reign in our country. But, later on what it was used for nobody knows. Just imagine how that huge magnet was made to stand just by the use of very basic tools. This speaks of the difficulty in constructing structures belong to the typology of stone temples.Now, when the importance of Constantinople came into existence, there was a sudden need for the construction of several public buildings. At that time there was a huge ceding back in the field of construction in Europe. There was a shortage of imaginations, funds, architects and even labourers. This thing gave rise to a new form of architecture. This form of architecture came to be known as Polymath Architecture. In this form of architecture the existing buildings were used to build several other buildings. The Roman basilicas were used to build the basilican churches that formed the basis of Christianity. The columns of the condemned buildings were actually truncated to get a uniform size. As a result, the buildings were having a size very close to the human scale. explicitly or purposely, this form of architecture happened to be more close to people. Even the foundations of several buildings wer e used to meet the needs of the times. The rotunda buildings were used to used to build baptisteries when the question of child baptism came into existence. These spaces required a kind of radiating building plan in order to accommodate the required activity. So, the unavailability of resources at that time was intercommunicate in such a way.Now, when we come to construction of buildings that are built with the on public money, the question of minimalism comes into existence. The usage of minimum amount of resource and funds comes into existence. Taking the example of a case, when an architect is given task of designing a public building, he has to make sure that he does not raise the cost of the building to the height of making it unfeasible. Nowadays, in case of construction of public buildings, the factor of tender pops up. The person coming up with the most apt design within the least of cost frame usually gets the project. Such a case can be taken up when it comes to the Bilba o museum. It was designed by Frank O Gehry. He had gone by the criticism of the entire world because of his design. His design was so complex that it made use of aircraft design software. He had actually gone to the point of overusing resources. The frames of the building were made using thick steel sections. A large layer of fabric was used to handle the building. Above this a layer of titanium sheets were used. Around twenty four thousand square meters of such were used. As a result of this, he was criticised over the fact that a similar functionality and aesthetics was achievable with lesser use of resources. But, he had paid no heed to what the people said. He has a idea of a fish just because he had memories of going to a fish market with his grandma. This vague justification brought about a lot of talks throughout the world. Luckily, the titanium prices had gone down at that point of time. So, he had the privilege of not getting the project cancelled.When residential projec ts are taken into consideration, there are several pety issues that come up. Funds remain limited in most cases. There have been cases when construction of a single house has gone through a ceasework period of more than a year just due to the lack of funds. Other religious issues play a vital role in our country when it comes to construction of residences specially. Several people actually back out when the architect is reluctant to listen to his specifications about how the building should be.Industrial buildings have challenges that are totally different as compared to other buildings. They should have the ability to actually justify all the government norms regarding the minute points like waste generation and opportunity safety factors. They should have special anthropometric specifications but they should not use too much of space.So, as we come to conclude this, we can actually draw that several issues are getting solved in this context. Several architects are coming up with innovative ideas to actually cater to the ideas of the government and the environmental equal assessment bodies to make a statement regarding this matter. So let us hope for a hassle free and green future aheadReferences storey Of Architecture by Sir Bannister FletcherConstruction Delays Extension Of time and prolongation claims by Roger Gibson

Saratoga Race Course :: essays research papers fc

Saratoga Race course     On July 27, 1783, George Washington and his men stood over a bubbling ambush, that hole was releasing water that to them was salty and smelled as if it had a high sulfur content. This water would be known as Saratoga mineral water. Saratoga residents adust spring water cultivated cabbage for Washington and his men, with out adding any salt or yeast and yet within a matter of minutes the bread rose. George Washington was considered to be Saratogas first visitor or tourist on that day. almost fifty years before Washington came to this water hole the Mohawk Indians used the local waters as a cleanser, for medicinal purposes and for drinking (Hotaling 1). George never did buy the land of Saratoga Springs that he had valued so bad. George was having trouble with real estate deals he was actually going to buy Saratoga Springs. George had said that Saratoga was the turning point of the revolution. George also impudently that Saratoga had great mineral water that could lead to industry. George enjoyed Saratogas environment, people gambling and playing billiard, while women road through on horses (Hotaling, 2-3).     Almost one hundred years later the birth of Saratoga racing had begun. In 1863, during the middle of the civil war, the Saratoga association was formed. The Saratoga association was a continuation of Saratoga attractions such as boxing, gambling, and what brought people to famous Saratoga in the first place, its water. In 1863, a racing meet for thoroughbreds marked the reservoir of "the oldest rush along track in America."(Longrigg, 222-223) The race course bears the additional distinction of being the oldest sports facility in the country. With the exception of 1911 and 1912, when the track closed in answer to gambling reforms, and 1943-45, when meets were cancelled due to World War II, the track has continued to operate and grow in popularity. Attendance at the famous Tra vers Day race has been known to double the citys population.     Health and Horses are the foundation of Saratogas History. Without the springs, settlers might easily have passed the region. Mineral water, for drinking and bathing, a European tradition for the health conscious, was the potency for the development of the city. The arrival of the railroad in 1831 was a huge boost in tourism.     The summer season at Saratoga offered diversions as well scorching air balloon ascensions, hops, balls, Indian encampments, and afternoon carriage rides down Broadway where people and horses were decorated in the latest finery.

The Great Depression of the 1930s in Canada Essay -- World History

The Great Depression of the 1930s in Canada The Great Depression of the 1930s is a benchmark for all in all embossments and recessions in the past and in the future. In the booklet The Great Depression of the 1930s in Canada , Michiel trumpet gives an intellectual dissection of the events that occurred during the Great Depression. Michiel bird of nights approach leaves the reader with a foul taste for the Dirty Thirties. This essay will summarize Michiel Horns key points as well as discuss the ability of Michiel Horn to report his findings. Michiel Horn is currently the Chairman of the History Department at York University. His interests in the Great Depression revolve around the history of taxation. Therefore, he is interested in reservation sure that this sequence of events is fully understood so that future generations never allow it to happen again.There are several ca expenditures of the Great Depression which Michiel Horn touches on throughout his writings. The in itial tool that he used to help understand the situation was to look at statistical data from that time. Through use of this data, a greater understanding of the physical heavilyships could be quantified and compared to present day. The reading begins with statistics about the shocking rate of unemployment. In 1933, at the height of the depression, the unemployment rate was between 19.3and 27 percent. The industrial activity in 1933 was only 57 percent of the average activity for the years 1925-29. The causes for the Great Depression were easy to see, but hard to fix. The problems included the inability of foreign countries to purchase surplus goods produced by other countries. Before the Great Depression, the British used this tactic to stabilize the market. Unfort... ...ults of the recession. In pose for this never to happen again, there is a need to learn from the mistakes in the past and to look for the warning signs. The problem is not just restricted to ane co untry, but is a global problem and needs to be addressed as such. The Great Depression often seems very distant to people of the twenty-first century. This article is a good reminder of potential problems that may reoccur. The article showed in a very literal way the idea that a depression can bring a growing country to its knees. The overall ramifications of the event were never discussed in detail, but the historical significance is that peoples lives were put on set aside while they tried to struggle through an extremely difficult time. BibliographyMichiel, Horn. The Great Depression of the 1930s in Canada. Ottawa The Canadian Historical Association, 1984.