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18/12/2023

18/12/2023

18/12/2023

25/09/2023

In Egyptian architecture, to which belong some of the earliest extant structures to be called architecture (erected by the Egyptians before 3000 BC), the post-and-lintel system was employed exclusively and produced the earliest stone columnar buildings in history. The architecture of W Asia from the same era employed the same system; however, arched construction was also known and used. The Chaldaeans and Assyrians, dependent upon clay as their chief material, built vaulted roofs of damp mud bricks that adhered to form a solid shell.

After generations of experimentation with buildings of limited variety the Greeks gave to the simple post-and-lintel system the purest, most perfect expression it was to attain. Roman architecture, borrowing and combining the columns of Greece and the arches of Asia, produced a wide variety of monumental buildings throughout the Western world. Their momentous invention of concrete enabled the imperial builders to exploit successfully the vault construction of W Asia and to cover vast unbroken floor spaces with great vaults and domes, as in the rebuilt Pantheon (2d cent. AD;).

25/09/2023

Architecture the art of building in which human requirements and construction materials are related so as to furnish practical use as well as an aesthetic solution, thus differing from the pure utility of engineering construction. As an art, architecture is essentially abstract and nonrepresentational and involves the manipulation of the relationships of spaces, volumes, planes, masses, and voids. Time is also an important factor in architecture, since a building is usually comprehended in a succession of experiences rather than all at once. In most architecture there is no one vantage point from which the whole structure can be understood. The use of light and shadow, as well as surface decoration, can greatly enhance a structure.

The analysis of building types provides an insight into past cultures and eras. Behind each of the greater styles lies not a casual trend nor a vogue, but a period of serious and urgent experimentation directed toward answering the needs of a specific way of life. Climate, methods of labor, available materials, and economy of means all impose their dictates. Each of the greater styles has been aided by the discovery of new construction methods. Once developed, a method survives tenaciously, giving way only when social changes or new building techniques have reduced it. That evolutionary process is exemplified by the history of modern architecture, which developed from the first uses of structural iron and steel in the mid-19th cent.

Until the 20th cent. there were three great developments in architectural construction—the post-and-lintel, or trabeated, system; the arch system, either the cohesive type, employing plastic materials hardening into a homogeneous mass, or the thrust type, in which the loads are received and counterbalanced at definite points; and the modern steel-skeleton system. In the 20th cent. new forms of building have been devised, with the use of reinforced concrete and the development of geodesic and stressed-skin (light material, reinforced) structures.

25/09/2023

The growth of credit cards has had an enormous impact on the economy—changing buying habits by making it much easier for consumers to finance purchases and by lowering savings rates (because consumers do not need to save money for larger purchases). Oil companies, car makers, and retailers have also used the cards to market their goods and services, using credit as a way of encouraging consumers to buy. Concern has been voiced over widespread distribution of bank credit cards to consumers who may not be able to pay their bills; costly losses and theft of cards; inaccurate (and damaging) credit records; high interest rates on unpaid balances; and excessive encouragement of consumer debt that has cut savings in the United States.

Technology advances have facilitated the use of credit cards. Merchants are now connected to banks by modem , so purchases are approved rapidly; on-line shopping on the Internet is possible with credit card payment. Credit card companies are also experimenting with smart cards that would act like a small computer, storing account and other information necessary for its use. An alternative to credit cards is the debit card , which is used to deduct the price of goods and service directly from customers' bank balances.

25/09/2023

Credit card device used to obtain consumer credit at the time of purchasing an article or service. Credit cards may be issued by a business, such as a department store or an oil company, to make it easier for consumers to buy their products. Alternatively credit cards may be issued by third parties, such as a bank or a financial services company, and used by consumers to purchase goods and services from other companies. There are two types of cards—credit cards and charge cards. Credit cards such as Visa and MasterCard allow the consumer to pay a monthly minimum on their purchases with an interest charge on the unpaid balance. Charge cards, such as American Express, require the consumer to pay for all purchases at the end of the billing period. Consumers may also use bank cards to obtain short-term personal loans (including "cash advances" through automated teller machines). Credit card issuers receive revenue from fees paid by stores that accept their cards and by consumers that use the cards, and from interest charged consumers on unpaid balances.

Diners Club became the first credit card company in 1950, when it issued a card allowing members to charge meals at 27 New York City restaurants. In 1958, Bank of America issued the BankAmericard (now Visa), the first bank credit card. In 1965, only 5 million cards were in circulation; by 1996, U.S. consumers had nearly 1.4 billion cards, which they used to charge $991 billion in goods annually.

15/06/2023

In addition to the UN member states, a number of NGOs promoting clean water and sustainable aquatic habitats have used World Day for Water as a time to focus public attention on the critical water issues of our era. Every three years since 1997, the World Water Council has drawn thousands to participate in its World Water Forum during the week of World Day for Water. Participating agencies and NGOs have highlighted issues such as a billion people being without access to safe water for drinking and the role of gender in family access to safe water.

13/06/2023

Pollution is the degradation of natural environment by external substances introduced directly or indirectly. Human health, ecosystem quality and aquatic and terrestrial biodiversity may be affected and altered permanently by pollution.

Pollution occurs when ecosystems cannot get rid of substances introduced into the environment. The critical threshold of its ability to naturally eliminate substances is compromised and the balance of the ecosystem is broken.

The sources of pollution are numerous. The identification of these different pollutants and their effects on ecosystems is complex. They can come from natural disasters or the result of human activity, such as oil spills, chemical spills, nuclear accidents … These can have terrible consequences on people and the planet where they live: destruction of the biodiversity, increased mortality of the human and animal species, destruction of natural habitat, damage caused to the quality of soil, water and air…

12/06/2023

One of the myths associated with the Great Wall of China is that it is the only man-made structure that can be seen from the Moon with the naked eye. The legend originated in Richard Halliburton’s 1938 book Second Book of Marvels. However, this myth is simply not true. Richard Halliburton’s claim was contradicted by astronauts Neil Armstrong and Yang Liwei. A more plausible assumption would be to say that the Great Wall can be visible from a low orbit of the Earth which is not unique in this regard as many other artificial constructions can be seen from that height.