Lider news

21/05/2024

The prime purpose of radio is to convey information from one place to another through the intervening media (i.e., air, space, nonconducting materials) without wires. Besides being used for transmitting sound and television signals, radio is used for the transmission of data in coded form. In the form of radar it is used also for sending out signals and picking up their reflections from objects in their path. Long-range radio signals enable astronauts to communicate with the earth from the moon and carry information from space probes as they travel to distant planets. For navigation of ships and aircraft the radio range, radio compass (or direction finder), and radio time signals are widely used. Radio signals sent from global positioning satellites can also be used by special receivers for a precise indication of position (see navigation satellite). Digital radio, both satellite and terrestrial, provides improved audio clarity and volume. Various remote-control devices, including rocket and artificial satellite operations systems and automatic valves in pipelines, are activated by radio signals. The development of the transistor and other microelectronic devices led to the development of portable transmitters and receivers. Cellular and cordless telephones are actually radio transceivers. Many telephone calls routinely are relayed by radio rather than by wires; some are sent via radio to relay satellites. Some celestial bodies and interstellar gases emit relatively strong radio waves that are observed with radio telescopes composed of very sensitive receivers and large directional antennas.

Transmission and Reception of Radio Waves

For the propagation and interception of radio waves, a transmitter and receiver are employed. A radio wave acts as a carrier of information-bearing signals; the information may be encoded directly on the wave by periodically interrupting its transmission (as in dot-and-dash telegraphy) or impressed on it by a process called modulation. The actual information in a modulated signal is contained in its sidebands, or frequencies added to the carrier wave, rather than in the carrier wave itself. The two most common types of modulation used in radio are amplitude modulation (AM) and frequency modulation (FM). Frequency modulation minimizes noise and provides greater fidelity than amplitude modulation, which is the older method of broadcasting. Both AM and FM are analog transmission systems, that is, they process sounds into continuously varying patterns of electrical signals which resemble sound waves. Digital radio uses a transmission system in which the signals propagate as discrete voltage pulses, that is, as patterns of numbers; before transmission, an analog audio signal is converted into a digital signal, which may be transmitted in the AM or FM frequency range. A digital radio broadcast offers compact-disc-quality reception and reproduction on the FM band and FM-quality reception and reproduction on the AM band.

21/05/2024

The first descriptions of Ottawa's future site were written by the founder of New France, Samuel de Champlain, in 1613. The rivers served as passageways for explorers and traders over the following two centuries. The Napoleonic Wars increased Britain's need for shipbuilding timber, and the Ottawa Valley offered just such resources. In 1800 an American, Philemon Wright, had begun timbering across the Ottawa River in what became the city of Hull. During the War of 1812 between Britain and the United States, the Rideau provided the British with a safe shipping route from the Ottawa River to Kingston, on Lake Ontario, thus spurring settlement of Ottawa. It was hastened by the arrival in 1826 of Lt. Col. John By of the Royal Engineers to work on canalizing the river, and the town became Bytown.

Ottawa might still be a modest city had not political quarrels between Quebec city and Toronto and between Montreal and Kingston induced leaders to call upon Queen Victoria to designate a capital for United Canada. In 1855 Bytown was incorporated and rechristened Ottawa after the Indian tribe. It became the fastest growing metropolis in eastern Canada, a development due largely to the presence of the national government. In 1937 Prime Minister William L. Mackenzie King brought the architect Jacques Grйber from France to begin the redevelopment of the national capital district.

The fur trade and lumbering have diminished in importance, and industry now employs only a small fraction of the labour force. The federal government is the major employer. Many commercial and financial associations from around the country as well as embassies and trade associations are also located there.

Ottawa is served by both of Canada's major railroads and several airlines. There is bus service throughout the city. Navigation on the Ottawa and Rideau rivers, except for pleasure craft, is a thing of the past.

The major cultural centres remain the city's three universities. The University of Ottawa and St. Paul University are bilingual institutions, whereas instruction at Carleton University is entirely in English. A large community college, Algonquin, provides technical training. Ottawa also houses the National Arts Centre, which includes an opera house and two theatres, the National Library and Public Archives Building, the National Museum of Science and Technology, and the National Gallery of Canada. Pop. (1991) city, 313 987; Ottawa-Hull metropolitan area, 920 857.

08/12/2023

12/10/2023

"In order to help develop and enhance positive self esteem, a youth sports program must make sure that every kid feels like he or she belongs on the team," Burnett says. "At the recreation level, the real value of sports is that everybody plays."

"Unfortunately, in many situations in America now, in youth sports, and recreational level especially, the less talented kids are being trained to be spectators -- to root for the handful of kids who will be the representative all-stars," he says.

Also, in many leagues, some experts are concerned that the focus is on winning, a team's place in the standings and making it to post-season play.

"At the real early ages until about the age of 10," says Gould, "you don't really need to worry about score. A lot of parents are forgetting this fun and fundamentals stage."

There are two ways to motivate a kid to play sports, Burnett says.

One negative method is an all-or-nothing approach:"You have to beat the competitor. You are only as good as the competitor you defeat. There is no place for second place."

He suggests an alternate philosophy that motivates kids to participate in sports by getting them to judge their success based on the skills they develop, regardless of outcome.

"Now you're competing against yourself. You focus on the skills," Burnett says. "The top athletes focus on tasks, not on trophies."

Regardless of what type of program you and your children choose, "When all the dust settles," Burnett urges parents, "You need to make sure that when you look at your child, that you relate to your child as a kid first and an athlete second."

12/10/2023

When it comes to signing your child up for a sports program, look before you leap.

Ask yourself, "Why do I want my child to play sports?" Ask your child, "Why do you want to play sports?" And ask the program director, "What can you offer my child?"

A good program should provide children with all the positive values that sports have to offer -- and feed their reasons for playing.

There is no denying the benefits of participating in sports. Aside from the obvious health benefits that come with activity and exercise, research shows that there are strong physical, social and psychological rewards associated with competition.

Dan Gould, the director of the Michigan State University Institute for the Study of Youth Sports, stresses that when children participate in multiple sports at an early age, they can develop the "ABCs of sports -- agility, balance and coordination."

He adds that children can learn both fundamental motor skills, such as running or throwing, and sport-specific skills that will help them to stay active well into adulthood.

In addition to skill development, given the right environment, research has shown that sports can have a positive psychological impact on kids.

Dr. Darrell Burnett, a clinical psychologist and certified sports psychologist specializing in youth sports in Laguna Niguel, California, suggests that participation in sports meets the four basic needs that contribute to our self-esteem.

"When kids play sports, they can have the opportunity to feel that they belong, feel like they are worthwhile just for being kids, be treated with respect and learn about a sense of emotional control."

For those students who continue to play sports into high school, valuable skills learned on the field can be transferred to the real world.
Employers know that to be successful, student athletes must have developed skills such as self-discipline, decision-making, problem solving and time-management.

With all of the benefits to playing sports, how can parents motivate their kids to play sports year after year?

Experts recommend finding out what's driving the kids first.

Recent studies conducted at the Michigan State University Institute for the Study of Youth Sports reveal that kids are motivated to play sports by a variety of factors.

"Kids want to have fun, improve their skills, be with their friends, get some physical activity," says Gould. "They like to win, but it's not the top reason nor the only reason."

And while sports have real value for kids, experts caution that children will not just catch the positive effects by showing up for practices or on game day. To reap the benefits of sports, they say that children need to be a part of a youth sports program that promotes mutal respect and encouragement.

12/10/2023

Fable brief allegorical narrative, in verse or prose, illustrating a moral thesis or satirizing human beings. The characters of a fable are usually animals who talk and act like people while retaining their animal traits. The oldest known fables are those in the Panchatantra, a collection of fables in Sanskrit, and those attributed to the Greek Aesop, perhaps the most famous of all fabulists.

Other important writers of fables include Jean de La Fontaine, whose fables are noted for their sophistication and wit, the Russian poet Ivan Krylov, and the German dramatist and critic Gotthold Lessing, who also wrote a critical essay on the fable. In England the tradition of the fable was continued in the 17th and 18th cent. by John Dryden and John Gay. The use of the fable in the 20th cent. can be seen in James Thurber's Fables for Our Time (1940) and in George Orwell's political allegory, Animal Farm (1945).

The American poet Marianne Moore wrote poems quite similar to fables in their use of animals and animal traits to comment on human experience; she also published an excellent translation of The Fables of La Fontaine (1954).

05/05/2023

This panic, incidentally, only made Frank more certain as to what he really wanted to do – now that he had this free money, he would go into business for himself. Even Tighe’s offer of a minor partnership failed to tempt him.

“I think you have a nice business,” he explained, in refusing, “but I want to get in the note-brokerage business for myself. I don’t trust this stock game. I’d rather have a little business of my own than all the floor work in this world.”

“But you’re pretty young, Frank,” argued his employer. “You have lots of time to work for yourself.” In the end he parted friends with both Tighe and Rivers. “That’s a smart young fellow,” observed Tighe, ruefully.

01/05/2023

During all these days young Cowperwood was following these financial complications with interest. He was not disturbed by the cause of slavery, or the talk of secession, or the general progress or decline of the country, except in so far as it affected his immediate interests. He longed to become a stable financier; but, now that he saw the inside of the brokerage business, he was not so sure that he wanted to stay in it. Gambling in stocks, according to conditions produced by this panic, seemed very hazardous. A number of brokers failed. He saw them rush in to Tighe with anguished faces and ask that certain trades be cancelled. Their very homes were in danger, they said. They would be wiped out, their wives and children put out on the street.

26/04/2023

In less than a week Cowperwood knew the financial condition of the Messrs. Waterman as well as they did – better – to a dollar. He knew how their accounts were distributed; from what section they drew the most business; who sent poor produce and good – the varying prices for a year told that. To satisfy himself he ran back over certain accounts in the ledger, verifying his suspicions. Bookkeeping did not interest him except as a record, a demonstration of a firm’s life. He knew he would not do this long. Something else would happen; but he saw instantly what the grain and commission business was – every detail of it. He saw where, for want of greater activity in offering the goods consigned – quicker communication with shippers and buyers, a better working agreement with surrounding commission men—this house, or, rather, its customers, for it had nothing, endured severe losses.

We are a team of professionals with over 20 years of experience

21/04/2023