1. Brown Dwarfs

A brown dwarf is a celestial body that has never quite become a star. A typical brown dwarf has a mass that is 8 percent or less than that of the Sun. The mass of a brown dwarf is too small to generate the internal temperatures capable of igniting the nuclear burning of hydrogen to release energy and light.

A brown dwarf contracts at a steady rate, and after it has contracted as much as possible, a process that takes about 1 million years, it begins to cool off. Its emission of light diminishes with the decrease in its internal temperature, and after a period of 2 to 3 billion years, its emission of light is so weak that it can be difficult to observe from Earth.

Because of these characteristics of a brown dwarf, it can be easily distinguished from stars in different stages of formation. A brown dwarf is quite distinctive because its surface temperature is relatively cool and because its internal composition-approximately 75 percent hydrogen- has remained essentially the same as it was when first formed. A white dwarf, in contrast, has gone though a long period when it burns hydrogen, followed by another long period in which it burns the helium created by the burning of hydrogen and ends up with a core that consists mostly of oxygen and carbon with a thin layer of hydrogen surrounding the core.

It is not always as easy, however, to distinguish brown dwarfs from large planets. Though planets are not formed in the same way as brown dwarfs, they may in their current have some of the same characteristics as a brown dwarf. The planet Jupiter, for example, is the largest planet in our solar system with a mass 317 times that of our planet and resembles a brown in that it radiates energy based on its internal energy. It is the mechanism by which they were formed that distinguishes a high-mass planet such as Jupiter from a low-mass brown dwarf.

2. Pulsars

There is still much for astronomers to learn about pulsars. Based on what is known, that term pulsar is used to describe the phenomenon of short, precisely timed radio bursts that are emitted from somewhere in space. Though all is not known about pulsars, they are now believed in reality to emanate from spinning neutron stars, highly reduced cores of collapsed attars that are theorized to exist.

Pulsars were discovered in 1967, when Jocelyn Bell, a graduate student at Cambridge University, noticed an unusual pattern on a chart from a radio telescope. What made this pattern unusual was that, unlike other radio signals from celestial objects, this series of pulses had a highly regular period of 1.33730119 seconds. Because day after day the pulses came from the same place among the stars, Cambridge researchers came to the conclusion that they could not have come from a local source such as an Earth satellite.

As more and more were found, astronomers engaged in debates over their nature. It was determined that a pulsar could not be a star in as much as a normal star is too big to pulse so fast. The question was also raised as to whether a pulsar might be a white dwarf star, a dying star that has collapsed to approximately the size of the Earth and is slowly cooling off. However, this idea was so

rejected because the fastest pulsar known at the time pulsed around thirty times per second and a white dwarf, which is the smallest known type of star, would not hold together if it were to spin that fast.

The final conclusion among astronomers was that only a neutron star, which is theorized to be the remaining core of a collapsed star that has been reduced to a highly dense radius of only around 10 kilometers, was small enough to be a pulsar. Further evidence of the link between pulsars and neutron stars was found in 1968, when a pulsar was found in the middle of the Crab Nebula. The Crab Nebula is what remains of the supernova of the year 1054, and in as much as it has been theorized that neutron stars sometimes remain following supernova explosions, it is believed that the pulsar coming from the Crab Nebula is evidently just such a neutron star.

3. Limestone

Limestone caves can be spectacular structures filled with giant stalactites and stalagmites. These caves are formed when rainwater, which is a weak acid, dissolves calcite, or lime, out of limestone. Over time, the lime-laden water drips down into cracks, enlarging them into caves.

Stalactites’, which grow down from cave ceiling, are formed in limestone caves when groundwater containing dissolved lime drips from the roof of the cave and leaves a thin deposit as it evaporates. Stalactites generally grow only a fraction of an inch each year, but over time a considerable number may grow to be several yards long. In cases where the supply of water is seasonal, they may actually have growth rings resembling those on tree trunks that indicate how old the stalactites are.

Stalagmites are formed on the floor of a limestone cave where water containing dissolved lime has dripped either from the cave ceiling or from a stalactite above. They develop in the same way as stalactites, when water containing dissolved limestone evaporates. In some limestone caves with mature limestone development, stalactites and stalagmites grow together, creating limestone pillars that stretch from the cave floor to the cave ceiling.

4. Smart Energy

The next few decades will see great changes in the way energy is supplied and used.  In some major oil producing nations, peak oil has already been reached, and there are increasing fears of global warming.  Consequently, many countries are focusing on the switch to a low carbon economy. This transition will lead to major changes in the supply and use of electricity. Firstly, there will be an increase in overall demand, as consumers switch from oil and gas to electricity to power their homes and vehicles. Secondly, there will be an increase in power generation, not only in terms of how much is generated, but also how it is generated, as there is growing electricity generation from renewable sources. To meet these challenges, countries are investing in Smart Grid technology.  This system aims to provide the electricity industry with a better understanding of power generation and demand, and to use this information to create a more efficient power network.

Smart Grid technology basically involves the application of a computer system to the electricity network.  The computer system can be used to collect information about supply and demand and improve engineers ability to manage the system.  With better information about electricity

demand, the network will be able to increase the amount of electricity delivered per unit generated, leading to potential reductions in fuel needs and carbon emissions.  Moreover, the computer system will assist in reducing operational and maintenance costs.

Smart Grid technology offers benefits to the consumer too.  They will be able to collect real-time information on their energy use for each appliance.  Varying tariffs throughout the day will give customers the incentive to use appliances at times when supply greatly exceeds demand, leading to great reductions in bills.  For example, they may use their washing machines at night.  Smart meters can also be connected to the internet or telephone system, allowing customers to switch appliances on or off remotely.  Furthermore, if houses are fitted with the apparatus to generate their own power, appliances can be set to run directly from the on-site power source, and any excess can be sold to the grid.

5. Plate Tectonics

According to the theory of plate tectonics, the upper portion of the Earth’s lithosphere, which contains the heavier oceanic and the lighter continental crusts, consists of rigid plates that are in constant motion. This theory provides a cohesive model to explain the integrated actions of continental drift, seafloor spreading, and mountain formation.

The Earth’s plates are estimated to have an average depth of approximately 60 mile (or 100 kilometers), but they are believed to vary considerably in size. Some are estimated to be continental or even hemispheric in size, while other are believed to be much smaller. Though the actual boundaries and sizes and shapes of the plates are not known for sure, it has been postulated that there are six major plates and somewhere around the same number of smaller ones. Most of the plates consist of both sail (continental) and sima (oceanic) crust. They are in contrast movement, though they move at an extremely slow pace, and these movements cause frequent interactions between plates.

At this time, scientists have identified three different types of boundaries between plates. At a divergent boundary, plates are moving away from each other. This type of boundary occurs at an oceanic ridge, where new material is being added to the seafloor from deeper within the Earth. Shallow earthquakes and underwater volcanoes are associated with this type of plate activity. At a convergent boundary, plates are moving toward each other and collide, causing vast folding and crumpling along the edges of the plates. In addition to the folding and crumpling, one of the plates slowly folds under the other. The boundaries between convergent plates are generally found around the edges of ocean basins and are sometimes associated with deep ocean trenches. A third type of boundary is a transcurrent boundary, which involves two plates sliding past each other laterally, without the folding and crumpling that occurs at a convergent boundary. This type of boundary is thought to be far less common than the other two types of boundaries.

6. Solar system

Our solar system consists of an average star we call the Sun, the planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. It includes: the satellites of the planets; numerous comets, asteroids, and meteoroids; and the interplanetary medium. The Sun is the richest source of electromagnetic energy (mostly in the form of heat and light) in the solar system. The Sun's nearest known stellar neighbor is a red dwarf star called Proxima Centauri, at a distance of 4.3 light years away. The whole solar system, together with the local stars visible on a clear night, orbits the center of our home galaxy, a spiral disk of 200 billion stars we call the Milky Way. The Milky Way has two small galaxies orbiting it nearby, which are visible from the southern hemisphere. They are called the Large Magellanic Cloud and the Small Magellanic Cloud. The nearest large galaxy is the Andromeda Galaxy. It is a spiral galaxy like the Milky Way but is 4 times as massive and is 2 million light years away. Our galaxy, one of billions of galaxies known, is traveling through intergalactic space.

The planets, most of the satellites of the planets and the asteroids revolve around the Sun in the same direction, in nearly circular orbits. When looking down from above the Sun's north pole, the planets orbit in a counter-clockwise direction. The planets orbit the Sun in or near the same plane, called the ecliptic. Pluto is a special case in that its orbit is the most highly inclined (18 degrees) and the most highly elliptical of all the planets. Because of this, for part of its orbit, Pluto is closer to the Sun than is Neptune. The axis of rotation for most of the planets is nearly perpendicular to the ecliptic. The exceptions are Uranus and Pluto, which are tipped on their sides.

7. Geothermal Heating

Our dependence on fossil fuels is a huge problem. Fossil fuels emit pollutants into the air. And they are non-renewable. That means that once you use them, they can’t be restored. That is, we can’t create any more. Finally, like all scarce resources, they are expensive. So we have the incentive to find other energy sources.

One option comes from the Earth. Under the surface of the Earth, there is a natural source of heat. We can extract this heat and use it in our homes. We do this by putting a heat pump deep in the Earth. It pumps heat from the Earth into our homes in the winter. The energy is clean and it never runs out.

Unfortunately, you cannot get enough heat from the Earth to maintain a comfortable temperature in your home. You still have to use another source, such as electricity. However, if you use geothermal as your principal heating source, your second source of energy will not be exerted as much. This will bring down your heating costs during the winter months. Though geothermal heating systems are expensive to install, they save money in the long run.

8. Carbon Footprints

Humans are doing a lot of damage to the Earth. Our lifestyles rely on certain technologies. And many of these technologies require power. The sources of that power emit greenhouse gases. Theses gases pollute the air. Polluting the air has serious implications. For one thing, it is not healthy to breathe polluted air. In addition, greenhouse gases cause the Earth’s temperature to rise. This causes

changes in the climate. Climate change is responsible for extreme weather like floods, droughts, and storms.

Sometimes the problem seems overwhelming. Individuals wonder what they can do. One way to grasp the subject is through the idea of a carbon footprint. This is the amount of greenhouse gases we are each responsible for. So, instead of feeling overwhelmed by the enormity of the problem, we can do something. We can reduce our carbon footprint.

How can we change our lifestyles to minimize our carbon footprints? First, we can assess our current level of consumption. Then, we can explore ways to reduce it. If we have to drive, we can set a limit to how much we drive. Then, we may not exceed this limit. But what if we do exceed it?

The other positive thing we can do is offset our carbon footprint. This means doing positive things for the Earth to counter the negative things we do. For example, we can plant trees. Trees filter the air and also serve as an energy source.

9. E-books

These days it seems that everything is going digital. Books are no exception. The e-book was designed to take the place of the printed book. It is a hand-held device. Text appears on a screen, just like a computer.

There are several advantages to the e-book. For one thing, it takes up less space. E-books are capable of storing hundreds of books. Therefore, readers will no longer need bookshelves to store all of their books.

Another distinction between the e book and normal books is that it is like a computer. Users can search for certain words in a book, or links to other texts can be included. This can make research less time consuming.

Readers with difficulty reading will note another important difference between books and their digital media equivalent. They can change the text size to make it easier to read. Further, a text –to-speech version of the software can be added so that they can listen instead of reading.

From the publisher’s point of view, distribution is made easier. Books are easy to replicate. The need for paper and ink is eliminated. And books don’t have to be shipped as they can be sent electronically.

10. Eco-friendly Computers

Computers are now part of our everyday lives. And they keep getting better. As they do, many people upgrade. That is, when a better product comes out, they get fid of their old one and replace it. The problem with this trend is that it creates a lot of waste. Corporate interests demand that consumers continually update their systems. This often results in a lot of waste. The solution is biodegradable computers.

In many ways computers can be seen as eco-friendly. They cut down on the amount of paper we need to use. That means we cut down less trees. Information can be shipped electronically. We don’t have to transport it by air, land, or sea. The amount of power it takes to run a computer is marginal. But the machines are made from toxic materials. They are not recyclable and they take up room in landfills.

A company called Micro Pro began working on a solution in 1992. It has since developed an eco-friendly computer. Items such as keyboards and monitors are made of wood and other biodegradable materials. That means

11. Wireless

Wi-Fi is a type of technology. It creates networks. These networks are wireless. Computers can communicate with one another without the use of wires. Internet connections can be made without wires. People can make phone calls over the internet. The telephone wires are not used. Such items as TVs and DVD players can be connected to networks using Wi-Fi technology. Wi-Fi technologies were introduced in 1997. Since then several versions have come out. Each one is an improvement on the previous one.

How is this possible? Wireless devices have to be capable of making a connection. They would all have to use the same technology. If one company uses one type of technology, another must use its equivalent. That’s the only way they can connect to the same network. So, different companies must work together to set standards. That way their different devices can work on the same network. The Wi-Fi Alliance sets these standards.

Wi-Fi is now common in corporate environments. People working in different locations can communicate easily. Distribution of tasks is simpler. People can work faster. There are fewer problems caused by delays. And the more access points, the more efficient the whole network is.

Hot spots are starting to appear in more places. These are areas where Wi-Fi is available for free. Anyone who happens to be in the area can use it. They just have to have a Wi-Fi certified device. These hot spots might be might be at a café, a hotel, an airport, or even an entire city. Some cities provide free wireless internet access.

Another good thing about Wi-Fi is cost. It gets rid of the need for cables. These can be costly to install. The cost of installing a wireless local area network is marginal in comparison. Wi-Fi also makes it easier to expand existing networks.

Wi-Fi technology has changed the way we do business. It has also changed the way we live our lives. The internet is more accessible than ever. And we can easily network our computers with others. The internet is now part of our everyday lives.

12. The Kyoto Protocol

The countries of the world often argue about environmental issues. Some are very vocal about global warming because they think it is very dangerous. They think that countries like the US use too

many fossil fuels such as oil. Using too much of these fuels hurts the environment and causes global warming.

Global warming is changing our weather. There are more floods and storms in many places. Often, many people are killed in floods. For years, scientists have warned us that we have to use less fuel.

There have been successive meetings between leaders to figure put what to do. One of the most important conferences took place in Japan in 1997. It was held in the city of Kyoto. Leaders from many countries assembled in a meeting room there to talk about what to do. They talked a lot and then some of them agreed to try to halt global warming. They signed a document called “The Kyoto Protocol”.

Some countries did not want to stop using fossil fuels and their leaders did not sign at Kyoto. They thought scientists were lying and making things sound more serious than they are. Some countries that sell oil to the rest of the world did not want to sign. They were scared their countries would become poor if people used less oil. Leaders who signed believe we can find new forms of energy. They pay scientists to find out what we can do. Many scientists believe we can use the Sun to make energy. We can also use wind or water.

13. What is Electricity?

Electricity is a form of energy. Electricity is the flow of electrons. All matter is made up of atoms, and an atom has a center, called a nucleus. The nucleus contains positively charged particles called protons and uncharged particles called neutrons. The nucleus of an atom is surrounded by negatively charged particles called electrons. The negative charge of an electron is equal to the positive charge of a proton, and the number of electrons in an atom is usually equal to the number of protons. When the balancing force between protons and electrons is upset by an outside force, an atom may gain or lose an electron. When electrons are "lost" from an atom, the free movement of these electrons constitutes an electric current. Electricity is a basic part of nature and it is one of our most widely used forms of energy. We get electricity, which is a secondary energy source, from the conversion of other sources of energy, like coal, natural gas, oil, nuclear power and other natural sources, which are called primary sources.

How is electricity generated? An electric generator is a device for converting mechanical energy into electrical energy. The process is based on the relationship between magnetism and electricity. When a wire or any other electrically conductive material moves across a magnetic field, an electric current occurs in the wire. The large generators used by the electric utility industry have a stationary conductor. A magnet attached to the end of a rotating shaft is positioned inside a stationary conducting ring that is wrapped with a long, continuous piece of wire. When the magnet rotates, it induces a small electric current in each section of wire as it passes. Each section of wire constitutes a small, separate electric conductor. All the small currents of individual sections add up to one current of considerable size. This current is what is used for electric power.

14. Alternative resources of energy

Natural Gas, in addition to being burned to heat water for steam, can also be burned to produce hot combustion gases that pass directly through a turbine, spinning the blades of the turbine to generate electricity. Gas turbines are commonly used when electricity utility usage is in high demand.

Petroleum can also be used to make steam to turn a turbine. Residual fuel oil, a product refined from crude oil, is often the petroleum product used in electric plants that use petroleum to make steam.

Nuclear power is a method in which steam is produced by heating water through a process called nuclear fission. In a nuclear power plant, a reactor contains a core of nuclear fuel, primarily enriched uranium. When atoms of uranium fuel are hit by neutrons they fission (split), releasing heat and more neutrons. Under controlled conditions, these other neutrons can strike more uranium atoms, splitting more atoms, and so on. Thereby, continuous fission can take place, forming a chain reaction releasing heat. The heat is used to turn water into steam, that, in turn, spins a turbine that generates electricity.

Hydropower, the source for 9% of U.S. electricity generation, is a process in which flowing water is used to spin a turbine connected to a generator. There are two basic types of hydroelectric systems that produce electricity. In the first system, flowing water accumulates in reservoirs created by the use of dams. The water falls through a pipe called a penstock and applies pressure against the turbine blades to drive the generator to produce electricity. In the second system, called run-of-river, the force of the river current (rather than falling water) applies pressure to the turbine blades to produce electricity.

15. Materials Science

Every day we come into contact with many thousands of manufactured objects that are essential to modern life: the vehicles that we travel in; the clothes that we wear; the machines in our homes and offices; the sport and leisure equipment we use; the computers and phones that we can’t live without; and the medical technology that keeps us alive. Everything we see and use is made from materials derived from the earth: metals, polymers, ceramics, semiconductors and composites.

To develop the new products and technologies that will make our lives safer, more convenient, more enjoyable and more sustainable we must understand how to make best use of the materials we already have, and how to develop new materials that will meet the demands of the future. Materials Science and Engineering involves the study of the structure, properties and behavior of all materials, the development of processes to manufacture useful products from them, and research into recycling and environmentally friendly disposal.

The basic building block of all matter is the atom and there are 94 different types that occur naturally on earth. These are ‘the elements’ and include hydrogen, oxygen, carbon, silicon, iron, copper, and aluminum. All materials are made up of these atomic building blocks but differ in their microstructure: the types of atom they contain, the pattern in which the atoms are arranged and the way in which the atoms are joined together. The central concept in Materials Science and Engineering is that the properties and behavior of every material is dependent on its microstructure, and that microstructure can be controlled by the way in which the material is made and processed. Materials Scientists test the mechanical, physical, chemical and electrical properties of materials and explore how these properties depend on the microstructures they engineer and observe using high powered microscopes.

16. TelecommunicationTelecommunications service providers and equipment vendors today face significant

challenges as they address the multitude of changes and competitive challenges sweeping their industry. Networks are increasing in size and complexity as demand pressures grow and as new technologies — from wireless communications and fiber optics to multimedia, computers and advanced Internet technologies converge upon the network. As the competitive environment intensifies, it becomes increasingly important for service providers and equipment vendors to be able to react to changes quickly and effectively while maintaining the highest levels of performance and reliability.

One of the most important means of achieving these goals is the ability to efficiently model, manage, and optimize the next generation of telecommunications equipment and services. Telecommunications networks are among the most demanding environments in terms of performance and reliability, and as a result place enormous demands on the database management systems that are at the heart of most telecommunications equipment and services.

The next generation of telecommunications applications requires a new generation of database technology - technology that draws on the strengths of prior generation DBMS technology and blends them with the latest software advances; a DBMS designed from the ground up for the highest performance and reliability in concurrent, highly distributed, multiplatform environments with extremely large data storage requirements. The Versant ODBMS (object database management system) is such a product. Versant is a seventh generation DBMS combining the direct modeling of complex, graph/structured data with the power of today’s leading object programming languages combined with report oriented query capabilities. As a result, the Versant ODBMS allows telecommunications service providers and equipment vendors to solve problems that they have been unable to solve using older storage technologies.

17. Computer language

A computer language is the means by which instructions and data are transmitted to computers. Put another way, computer languages are the interface between a computer and a human being. There are various computer languages, each with differing complexities. For example, the information that is understandable to a computer is expressed as zeros and ones (i.e., binary language). However, binary language is incomprehensible to humans. Computer scientists find it far more efficient to communicate with computers in a higher level language.

Block-structured language Block-structured language grew out of research leading to the development of structured programming. Structured programming is based on the idea that any computer program can be written using only three arrangements of the information. The arrangements are called sequential, selection, and iteration. In a sequential arrangement, each programming instruction (statement) is executed one after the other. This order is vital. The execution of the second statement is dependent on the prior execution of the first statement.

PASCAL, ALGOL, and MODULA-2 are examples of block-structured languages. Examples of non-block structured languages are BASIC, FORTRAN, and LISP. Refinements of BASIC and FORTRAN produced more structured languages.

Block-structured languages rely on modular construction. A module is a related set of commands. Each module in a block-structured language typically begins with a "BEGIN" statement and ends with an "END" statement.

18. Nineteenth Century Photography

___The nineteenth century saw enormous advances in photography in the US. Photos from this time period can tell us about history. But they don’t just tell us about the subject of the photo. We can learn about the art of photography.___We can infer the date of a photo by the style. The daguerreotype, for example, was the earliest style in common use. A silver-plated, mirror-like metal sheet was used. It was placed in a camera and exposed to the image. The final image was sharp and full of detail.___The ambrotype was used from 1854 to the early 1860s. It became popular because it was cheaper than the daguerreotype. It used a glass plate to expose the image in the camera. Another glass plate was then attached to protect it. Then the thing was interested into a metal frame.___The ambrotype preceded the tintype. The tintype used a thin, black, metal plate instead of glass. It was invented in 1856. It was popular until the early 1900s. The photos didn’t have to be cased like ambrotypes. This was because they weren’t so fragile. ___These are just a few of the many techniques used in photography in America in the nineteenth century.

19. Visual Arts

Visual arts are arts that appeal to our sense of sight. As such, the possibilities for visual arts are endless. Paintings, drawings, film and sculptures are just a few examples. There has been some disagreement as to what should be included in the visual arts. Namely, should crafts be seen as such? There was a time when only fine arts could be included in the visual arts. Craftsmen were not thought to be artists. This era preceded the Arts and Crafts Movement which was founded in the early twentieth century. This movement helped create an appreciation for craftsmanship. Today, crafts too are considered visual arts. Our ideas of what constitutes art are always changing. ■ A modern example is graffiti. ■ Graffiti is seen by some as vandalism. ■ They think it is ugly. ■ But others see it as art. For one thing, it can be very beautiful. For another, it can make a strong statement about society. The visual arts are old as humanity. Some of the earliest examples of visual arts are cave paintings. These were made by early humans. They would often depict scenarios such as hunting. Such paintings not only tell us about the daily lives of these early humans, but they tell us something about their psyches. In other words, we can see what their lives were like, but we can infer something about the way their minds worked. For example, some cave paintings indicate that the artists held religious beliefs. A good visual artist does more than depict an image. He or she attaches meaning to that image. The hope is that it will invoke a certain emotional response in the viewer. The range of possible responses, of course, is enormous. Again, the work can tell us much about the subject. But it can tell us even more about the artist. There is a great diversity in the types of visual art available. And the possibilities are growing. New technologies allow for new genres. Computer graphics, for example, has opened up a world of possibilities to artists. And the quality gets better and better as technology improves.

20. Life Science

___Life Science is the study of all living things. It is the study of animals, humans, and plants. It is also the study of tiny living things that can only be seen with a microscope. We call these small things micro-organisms.___Life Science is also sometimes called biology. This word comes from two Greek words: ‘bio’, meaning ‘life’ and ‘logos’, meaning ‘to speak of’. Many scientific words come from Greek. This is because the ancient Greeks were some of the first people to try and understand nature. They wrote their ideas down and today we can still read them. ___Aristotle, a Greek philosopher, who lived from 384 BCE until 322 BCE, is known as the ‘father of biology’. He was one of the very first people to make highly accurate studies of animals and plants.___Aristotle had a lot of perseverance. He knew that he had to study the same animal or plant for a long time to get to know it. He studied living things carefully. He also did many experiments. He wrote down everything he saw.___Aristotle believed that all scientists had to be rigorous and that they could not guess. That is also why he did not confine his studies to one place. He traveled a lot. Today, life scientists still use many of his methods.

21. Evolution

In 1859, a man called Charles Darwin wrote a famous but controversial book. The book was called On the Origin of Species. It was about something called ‘evolution’. This was a very exciting idea about how animals and plants changed over millions of years. Darwin had traveled all over the world. He had studied many different plants and animals. He could see how they all adapted to their environments. He saw that animals that lived in deserts did not use a lot of water. He saw that animals that lived in the snow had thick fur to keep them warm. He decided that it took a long time for animals and plants to change like this. He thought it took thousands of years for them to change just a title. Darwin believed that people had also changed over time. He wrote that people and monkeys had come from the same animal. He had a colleague called Thomas Huxley who also thought so. They upset many people. The idea was incompatible with the Bible. The Bible said that God had made people. The church tried to prohibit students from learning about evolution. They thought Darwin’s ideas were evil. There was a lot of evidence to show that Darwin was right and his ideas could not be ignored. Darwin also saw how weaker animals often died while stronger animals didn’t. This meant that only the strongest and smartest animals would have babies. Darwin thought this was nature’s way of making sure that there would only be strong animals on Earth.

22. Effective Management and the Employee Interview

___The manager’s job is to make sure the business is running well. A big part of the business is the workers. They have to be doing their best for the business to be doing its best. So managers have to make sure workers are doing their best. To do this they have to be good leaders.

___Good leaders should understand why some people work hard and some don’t. ■ Then they can provide motivation for workers. ■ Money is not the only motivation for workers. ■ Workers want to know that they are appreciated. They want to feel like they are part of the company’s success. ■ ___ Managers need to enhance worker-manager relations. One way is to do brief interviews every three months. This allows managers to compile information. Workers can express their attitudes toward certain policies. Then they feel like they are being listened to. This makes them likely to be more cooperative.____■ It is important that workers know the purpose of the interview. If they think it is an evaluation they will perform differently. ■ The fear of termination can affect their level of honesty. ■ They should see the interview as a chance to express themselves. ■ Then it will be more productive.

23. Market Economy

Competition is the most important thing in a market economy. Firms compete with one another for business. This helps to keep prices reasonable. To get some insight into how this works, think of what would happen if firms cooperated. The motivation of every firm is to enhance their profit margins. One way to do this is to increase price. If all of the firms were cooperating, they could set any price. The consumer would have to pay it or do without the commodity being sold. In general, firms don’t cooperate. They compete. Consider this example. A pencil costs twenty-five cents to make. Firm A makes pencils and sells them for two dollars. Firm B sells them for one dollar. Firm B’s pencils are just as good as Firm A’s. Which firm will make more money? Well, if they sold an equal number of pencils, Firm A would. But they won’t sell an equal number of pencils. Firm B will sell more. This is because consumers will look for the best price. So, Firm B will sell more pencils and earn a greater profit. So, in general, the firm that offers the best product for the best price should turn the best profit. Increasing price will not enhance profit margins unless the competition does the same. There are situations in a market economy where no competition exists. This is called a monopoly. When a firm has no competition, it has a monopoly. ■ It can virtually set any price because consumers have only one option. ■ The other option is to do without the commodity. So the firm needs to compile data on the maximum amount consumers are willing to pay for their product. Then they can charge that price. Generally, though, if a firm has a monopoly, it won’t last. ■ The opening of new firms to compete with them will coincide with their initial success. ■ A steep inclination in the demand curve for a certain product will signal other suppliers to provide it. Furthermore, there are laws in place that keep firms from maintaining a monopoly in any industry.

24. Mining Process

In addition to the various types of deep mining, several types of surface mining may be used when minerals lie relatively close to the surface of the earth. One type is open-pit mining. The first step is to remove the overburden, the layers of rock and dirt lying above the ore with giant scrapers. The ore is broken up in a series of blasting operations. Power shovels pick up the pieces and load them into trucks or, in some cases, ore trains. These carry it up ramps to ground level. Soft ores are removed by drilling screws, called augers.

Another type is called placer mining. Sometimes heavy metals such as gold are found in soil deposited by streams and rivers. The soil is picked up by a power shovel and transferred to a long trough. Water is run through the soil in the trough. This carries soil particles away with it. The metal particles are heavier than the soil particles and sink to the bottom, where they can be recovered.

The finishing-off process of mining is called mineral concentration. In this process, the desired substances are removed from the waste in various ways. One technique is to bubble air through a liquid in which ore particles are suspended. Chemicals are added that make the minerals cling to the air bubbles. The bubbles rise to the surface with the mineral particles attached, and they can be skimmed off and saved.

25. Sericulture or Silk Production

Sericulture, or silk production, has a long and colorful history unknown to most people. Archaeological finds show that sericulture dates to at least 2500 B.C., and may be much older. For much that time, China kept the secret of silk to itself as one of the most zealously guarded secrets in history. Anyone revealing the secret of silkworm culture or trying to smuggle silkworm eggs out of China was punished by death.

The key to China’s domination of silk production lies with one species native to China: the blind, flightless moth Bombyx mori. This insect lays five hundred or more eggs in four or five days and dies soon after. The eggs are like pinpoints- one hundred of them weigh only one gram. From one ounce (28.3 grams) of eggs come about 30.000 worms (the larvae of the moth), which eat a ton of white mulberry leaves and produce twelve pounds (5.4 kilograms) of raw silk. The silkworm of Bombyx mori produces smoother, finer, and rounder thread than other silkworms. Over thousands of years, this Chinese moth has evolved into the specialized silk producer that it is today.

At one time, silk was reserved exclusively for the use of the Chinese emperor. Gradually, all classes of society began wearing silk. In addition to being used for clothing and decoration, silk came to have industrial uses in China. This is something that happened in the West only in modern times. Silk was used for musical instruments, fishing lines, bowstrings, bonds of all kinds, and even for manufacturing paper. During the Han Dynasty, silk became an absolute value in itself. Farmers paid taxes in both grain and silk. Values were calculated in lengths of silk as they had once been calculated in gold. The importance of silk is even reflected in all the dialects of the Chinese language. For example, of the 5.000 most common characters in the Mandarin alphabet, around 250 have silk as their key.

In spite of their secrecy, the Chinese eventually lost their monopoly on silk production. Sericulture reached Korea around 200 B.C. when immigrants from China arrived there. Sericulture came to India in A.D.550 when sericulture came to the West. Silkworms were carried by travelers in hollow tubes of bamboo to Constantinople. This allowed a silk industry to be established the Middle East and later Italy. However, high – quality Chinese silks still had a market in the West.

26. What is a business leader?

What is a business leader? Is it the same as a manager? There is certainly an overlap between these two roles, but as the business author Bernard bass wrote, “Some managers do not lead, and some

leaders do not manage.” There are some personality traits and behaviors that are characteristic of a leader, and some that are characteristic of a manager. For example, leaders are committed to innovation and tend to look to the future for threats and opportunities. Managers try to maintain the status quo and concern themselves with solving problems in the present.

Leadership and management are both important to a business organization. Once an organization is established, managers go about maintaining the system, assuming that the organization will always be the same. Management keeps the organization going. However, the environment in which an organization operates is always in flux. There are changes in consumer tastes, technology, cultures trends, and historic events. If the organization is entirely in the management mode, it may not spot these trends because managers tend to look inward. However, if the organization is in the leadership mode, it will track these changes and shape the organization to face new challenges and keep the organization relevant.

Here’s a classic example: In the 1950’s and 60’s, North American auto makers built large, heavy, powerful cars with gas-GUZZLING engines because that was what consumers wanted. The oil crisis of the early 1970’s however, shifted consumer attitudes towards lighter, smaller cars with more fuel-efficient engines. Being in management mode, the “Big Three”—the three major North American auto makers—were very slow to recognize this trend and continued to manufacture the kind of cars that they had made for years. Meanwhile, European and especially Japanese automakers had been making economical cars for years. During this period, The Big Three lost a great deal of market share to international automakers.

27. Computer Games

Computer games were designed and played as long ago as the 1950’s. The first known game was Tennis for Two (1958), designed by William Higginbotham. Another early game was Steve Russell’s Space war! (1961).These games never became very popular. It was not until the 1970’s and 80’s,when computer arcade games were introduced, that computer games attracted millions of game-players. The first to make splash was Pong (Atari, 1972).It was designed by Nolan Bushnell and Alan Alcorn. The game play was extremely simple. Two players bounced a moving ball back and forth between their two electronic paddles. Bushnell placed the first game machine in local gas station. When he returned in a few days, the machine was so full of coins that it could no longer operate. Pong became an instant success and it helped create the arcade game industry. Other blockbuster game such as Space Invaders (bally/Midway 1978), Asteroids (Atari, 1979), and Donkey Kong (Nintendo, 1981) followed. Perhaps the most popular arcade game ever, Pac Man (Bally /Midway, 1980) was based on an ancient Japanese folk tale. Some these arcade games, and other games that were not seen in arcades, were available for play on personal computers. It can even be said that computer games helped popularize the idea of owning a home computer and shaped the way computers were made. Steve jobs and Steve Woznaik (Who has met while designing games foe Atari) designed the Apple II. The first popular personal computer, so that it could be used to play computer games at home

Today there are four main types of devices that computer game can be played on. Personal computers consoles handheld consoles, and arcade machines are all common platforms. Personal Computer (PC) games are designed to be played on standard home computers. Often no special

controls are needed-the game can be played with a keyboard or mouse-but some games are played with a joy stick. Video feedback is received by the user thought the computer monitor and audio feedback through speakers or headphones. Players can buy PC games at the store-usually stored on CD ROMs-or download them from the internet. Players of PC game can also play against live opponents on the Internet.

28. Thomas Edison’s Invitation At the end of the 1800’s, Thomas Edison introduced the incandescent light bulb and changed

the world. Remarkably, the incandescent bulb used today has changed little in over a hundred years. An incandescent light consists of a glass bulb filled with an inert gas such as argon. Inside the bulb, electricity passes through a metal filament. Because of resistance, the filament becomes so hot that it glows. Given that 20% of the world’s electricity is used to power lights, this represents an enormous amount of wasted energy.

In the 1940’s a new, more efficient form of lighting, the fluorescent bulb, was introduced. Fluorescent work by passing electrical current through gas in a tube, producing invisible ultraviolet to visible light. A phosphor coating on the inside of the tube then converts the ultraviolet to visible light. Little heat is wasted. Fluorescents have proved popular in offices, factories, and stores, but they never took over the residential lighting market. The harsh color isn’t as pleasing as the warmer glow of incandescent lamps. Besides, they have a tendency to flicker on and off and to produce an annoying buzz.

Now, lighting engineers are developing a new form of lighting that is both pleasing to the eyes and energy efficient. This is the light- emitting diode, or LED. LEDs are made up of layers of electron- charged substances. When an electrical current passes through the layers, electrons jump from one layer to another and give off light without producing heat. Different types of materials result in light of different colors. Red, green, and orange LEDs have been used for decades in devices such as digital clocks, calculators, and electronic toys. In the future, however, white- light- emitting diodes (WLEDs) may be used to light homes. Engineers say that they are significantly more efficient than either incandescent or fluorescent lights.

Arrays of colored LEDs are beginning to be used in traffic lights and automotive lights. Today, colored light through a colored plastic filter. This is incredibly inefficient because only the red light that passes through the filter is used. The rest is wasted. Because LEDs actually produce red light, no filter is needed and no light is wasted. LEDs have other practical applications as well. For example, they can be used to light heat- sensitive materials like food or important documents.

29. Modern Architecture

The dissatisfaction with such a general situation at the turn of the twentieth century gave rise to many new lines of thought that served as precursors to Modern Architecture. Notable among these is the Deutscher Werkbund, formed in 1907 to produce better quality machine made objects. The rise of the profession of industrial design is usually placed here.

Following this lead, the Bauhaus school, founded in Germany in 1919, consciously rejected history and looked at architecture as a synthesis of art, craft, and technology.

When Modern architecture was first practiced, it was an avant-garde movement with moral, philosophical, and aesthetic underpinnings. Immediately after World War I, pioneering modernist architects sought to develop a completely new style appropriate for a new post-war social and economic order, focused on meeting the needs of the middle and working classes. They rejected the architectural practice of the academic refinement of historical styles which served the rapidly declining aristocratic order.

The approach of the Modernist architects was to reduce buildings to pure forms, removing historical references and ornament in favor of functionalist details. Buildings that displayed their construction and structure, exposing steel beams and concrete surfaces instead of hiding them behind traditional forms, were seen as beautiful in their own right. Architects such as Mies van der Rohe worked to create beauty based on the inherent qualities of building materials and modern construction techniques, trading traditional historic forms for simplified geometric forms, celebrating the new means and methods made possible by the Industrial Revolution.

Many architects resisted Modernism, finding it devoid of the decorative richness of ornamented styles. As the founders of the International Style lost influence in the late 1970s, Postmodernism developed as a reaction against the austerity of Modernism. Robert Venturi's contention that a "decorated shed" (an ordinary building which is functionally designed inside and embellished on the outside) was better than a "duck" (a building in which the whole form and its function are tied together) gives an idea of this approach.

30. Urban Design

Early human settlements were essentially rural. As surplus of production began to occur, rural societies transformed into urban ones and cities began to evolve, such as that of Katal Huyuk in Anatolia and Mohenjo Daro in India. In many ancient civilizations, such as that of the Egyptians' and Mesopotamians', architecture and urbanism reflected the constant engagement with the divine and the supernatural, while in other ancient cultures such as Persia architecture and urban planning was used to exemplify the power of the state.

The architecture and urbanism of the Classical civilizations such as the Greek and the Roman evolved from civic ideals rather than religious or empirical ones and new building types emerged. Architectural styles developed.

Cities in traditional societies were mostly very small by modern standards. Babylon, for example, one of the largest ancient cities of the Middle East, extended over an area only 3.2 square miles – and probably at its height. The world’s first cities appeared in about 3,500BC, in the river valleys of the Nile in Egypt, the Tigris-Euphrates in what is now Iraq, and the Indus in what is today Pakistan. Rome under Emperor Augustus was easily the largest ancient city outside China, having some 300,000 inhabitants.

Streets in cities serve many purposes besides carrying vehicles, and city sidewalks-the pedestrian parts of the streets – serve many purposes besides carrying pedestrians. Streets and their sidewalks, the main public spaces of a city, are its most vital organs. Think of a city and what comes to mind? Its streets. If a city’ streets look interesting, the city looks interesting; if they look dull, the city

looks dull. More than that, and here we get down to the first problem, if a city’s streets are safe from barbarism and fear, the city is thereby tolerably safe from barbarism and fear. When people say that a city, or a part of it, is dangerous or is a jungle, what they mean primarily is that they do not feel safe on the sidewalks.

Urban design concerns the arrangement, appearance and functionality of towns and cities, and in particular the shaping and uses of urban public space. It has traditionally been regarded as a disciplinary subset of urban planning, landscape architecture, or architecture. However, with its increasing prominence in the activities of these disciplines, it is better conceptualized as a design practice that operates at the intersection of all three, and requires a good understanding of a range of others besides, such as urban economics, political economy and social theory.