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Điện thoại có cần thiết?
Are Cell Phones Necessary?
Sifting through his latest screenplay on the way to class, Geoff Yetter ignores the muffled sound of a computer-generated rendition of Johan Pachelbel’s Canon in D coming from inside his book bag.
“Porcupined onions,” he curses to himself. “I’ll call them back when I’m free.”
Yetter, a senior film and video studies major at the University of Oklahoma, said that although he has a cell phone, it is only because he considers them to be a “necessary evil.”
“At the risk of coming off as one of those ‘hippie’ types, I truly see a cell phone as a leash that ties you to a world that man shouldn't belong to,” he said. “No matter how much one tries, you can never escape anyone if you have a cell phone.”
Over 110 million Americans own a cell phone, according to a study done by the Cellular Telecommunications Industry Association (CTIA). With an average of 46,000 new subscribers every day, CTIA experts project that in 2005 there will be over 1.25 billion cell phone users worldwide.
Increasing numbers of college students are abandoning landlines in lieu of simply using their cell phones as their only contact number, said an Oct. 10, 2004 Wesleyan Argus article on the drop in dorm phone subscription rates at Wesleyan University. The article calls the drop so significant that landlines on campus “seem anachronistic.”
In a school like Northeastern University,a fast-paced, career-driven school in a major metropolitan area, having a cell phone is almost a necessity for students.
While there are many factors to consider when deciding to purchase a cell phone – convenience, price, minute plan, clarity of service, when it will be used, health risks– it comes down to a simple necessity of a convenience for most people, said the Argus article.
“I have my cell phone to keep in touch with friends and family from home,” said Kirsten Baxter, a junior mechanical engineering major at Northeastern University. “My family lives on the West Coast so it would be long distance on a regular phone so I (set up) a cell phone plan with nationwide minutes.”
Having a cell phone also makes more sense for her as a college student because with a landline she might have to set up a new number every time she moves in addition to it being obviously less portable, she said.
Many newer cell phone models are multimedia devices with “telephone” merely being one of the features. There are camera phones and various videogames and ring tones one can use on a cell. There is also the Nokia “N-Gage,” a gadget that is primarily a handheld videogame system that doubles as a cell phone and can be used to play multiplayer games across a cell network.
“I like having the games on my cell phone a lot because I commute too,” Baxter said, peering up from her match of cell phone Backgammon. “When I’m on the T it’s nice to have a mindless game to play.”
The radiation emitted from everyday cell phones in extended exposure has been proven to cause an increase in lymphocytes in mice through lab experiments, according to a study done in Radiation Research – a monthly journal published by the Radiation Research Society. Yet there is still no definitive answer on what the long-term health risks for humans may be.
“There have been several studies that examined this issue and reported that there was no significant difference in the incidence of brain tumors in cell phone users and non-users,” said Professor Robert Cersosimo of the Bouvé College of Health Sciences at Northeastern University. “However, there is more work to be done is this area and more studies are currently underway.”
While some students do consider these health risks and remain leery of them, others do not give them a second thought and spend literally thousands of minutes on their handheld phones every month.
“I sometimes worry about the risks of developing some kind of tumor from using my cell phone too much,” said Northeastern sophomore pharmacy major Jack Soohoo. “But it doesn’t stop me from using it.”
Soohoo estimates he uses his phone an average of 15 minutes each day – almost 500 minutes a month. That amount may be enough to do damage, but considering it as only a mere 15 minutes out of the day might be enough to create a false sense of security for users looking to rationalize the use of their phones in some way.
“I think the amount of time I spend using my cell phone is still insignificant and won’t be sufficient [enough] to cause cancer,” said Soohoo.
Baxter has similar feelings, saying she thinks “common sense says it has the probably could cause cancer, but everything does” and that she’s not overly worried about it.
For those who do worry about the risks of radiation waves being transmitted close to their heads, protection devices exist that are intended to cut down on this potentially harmful radiation.
The “No-Wave – Anti Wave Antenna” technology by RF Safe incorporates “a simple natural process of nullifying energy around the user through an Interferometric Array or interference pattern that sends in-phase and out-of-phase energy to cancel each other out at point of intersection,” according to the company’s website.
The safeguard system was invented to prevent possible health effects and as a solution for an FCC mandate of the Americans with Disabilities Act to create a device that would let hearing impaired individuals to use cellular phones without having to remove their hearing aid.
According to the company’s website, radiation emitted from a cellular device penetrates into the skull of the user’s head while remaining at high levels, above that of the federally imposed Specific Absorption Rate (SAR) guidelines (Fig. 1). The image, which was created using electromagnetic imaging software, shows a reddened region surrounding the ear representing the reach of the most intense rays.
RF Safe claims their RF blocking device can significantly reduce this reddened region. When a phone is placed next to a handheld RF meter during a connected call, the radiation levels spike toward the highest readings. After the company’s protective device is equipped, the reading is significantly lower (Fig. 2). Whether or not these images are skewed to assist the company’s image, the radiation levels of an unprotected phone are still elevated.
Greta Merrick, a sophomore graphics design major at Northeastern who is opposed to owning a cell phone, said that while such data is frightening, the health risks are not a determining factor and something she “honestly wouldn’t consider that much.”
“I don’t know much about the health concerns,” she said. “I’ve only heard hearsay.”
For alternative methods of reducing exposure to radiation from a cell phone, the National Cancer Institute suggests reserving usage for only shorter conversations and in situations where a landline is not available, switching to a type of portable phone with a headset to keep the antenna away from the head, and for use in a car, switching to a kind of mobile phone with the antenna mounted outside the vehicle.
With the added portability cell phones offer, they can assist a businessman in getting added work done while on the run. They can be the charm a commuter student studying on the train needs as he makes arrangements for later that night, or they can serve as the liaison for a stock broker trying to get some extra buying and selling done while driving to lunch.
While this handiness can certainly increase the efficiency of and be a benefit for many people, the distraction that comes with this convenience can be dangerous.
“Studies have confirmed that people who use a cell phone while driving run the same risk of having an accident as a moderately intoxicated person,” said Professor of Northeastern University’s Sociology and Anthropology department Danny Faber. “In other words, holding onto a cell phone (with one hand) while driving with another dramatically increases your chance of having an accident.”
Driving while talking on a hand-held cell phone doesn’t just slightly increase one’s chances of getting in an accident, it increases those chances four-fold, according to a study done by the New England Journal of Medicine. That statistic is comparable to the one found regarding the increased occurrence of accidents among those driving while under the influence of alcohol.
As much of a potential hazard as this can be, 56 percent of college students surveyed at Northeastern University said they talk on their cell phones in the car all the time. On top of that, only six percent said they have never taken this liberty.
Professor in the Sociology and Anthropology department and Acting Chair at Northeastern Thomas Koenig said he thinks this shift in public phone conversations is, if nothing else, strange.
“I think it is interesting that people used to go into full booths (to talk on the phone in public),” said Koenig, mentioning where Superman changed in the old TV show as a reference. “Privacy and not bothering others was very important. Now people think little of blabbing their personal business to everyone passing nearby.”
With all this multitasking has come people taking their conversations into public places, often bothering those around them.
"Cell phones are still a pretty new technology," said Dr. Jack Levin, Professor and Director of the Brudnick Center on Conflict and Violence and Professor of Sociology at Northeastern. "We haven't yet developed norms for use. Some think it's okay to use in work, some think it's safe to drive (with one), some think it's okay to talk loudly in a crowded elevator."
Not as intimate
Merrick said that the main factors keeping her from using a cell phone are less about health and more about the cost and, chiefly, the lack of intimacy in conversing with someone on the go.
“They might be walking down the street or be at a party or in a hurry,” she said. “If they don’t tell you, you could start pouring out the story of your day and they can’t pay attention but they try to anyway.”
Merrick said she prefers the comfort and familiarity of using a home phone.
“If someone’s on a landline, you know they’re in their home – in their personal space, talking to you and listening to you,” she said. “The first question I usually ask someone if I’m calling their cell phone and actually want to talk to them is ‘Where are you’ or ‘What are you doing’ because otherwise I can’t relate to them and how can you talk to someone you’re not relating to?”
Professor Faber also prefers to remain living as he did before the inception of cell phones into society. While he said he believes one may certainly be risking one’s health when using one of the handheld devices, he mostly wants to be reached when he is in position to be reached – at home or in the office.
“I value my privacy, and don't want to be so accessible all of the time,” he said.
Yetter said he often feels the same way when he hears the beginning of the digital Canon in D, and resents the expectations of being available all the time to concentrate on a phone conversation.
“Anyone can track you down at any time, and when they are unable to, they get cross with you because they believe that, since you do have a cell, they are entitled to talk to you whenever they wish,” he said.
Yetter, like Merrick, says he also doesn’t consider the potential adverse health effects as one of the main deterrents.
“For me personally, I am unafraid of the health risks because I use my phone so little,” he said. “But as research developments continue and further evidence proves that these gadgets can be cancer-causing, it does make me worry for friends, family, and, well, everyone who uses one basically.”
Over 70 percent of college students who own a cell phone do not pay for their own bill, according to the survey conducted at Northeastern University.
Of those surveyed, only two of the 18 respondents said they actually pay for their entire bill, while another three either pay some of the bill each month or only in situations where they incur overage charges.
Most cell phone companies offer plans upon which customers pay a fixed rate per month and are given a set amount of minutes to use within certain time constraints. The most common plan cost of students surveyed is $39.99, yet one-third of students said they do not even know how much their cellular phone costs per month. T-Mobile and Verizon were both the most popular and highest rated services on a scale of one to 10, each garnering an average rating of just under 8. If the user goes over his or her allotted minutes, the user will have to pay overage charges, which typically range around 40 cents per minute.
In some cases, these excess charges for using more minutes than agreed upon in a contract can run up a steep bill. Sophomore journalism and marketing major Bessie King said one month she received her bill in the mail and was surprised upon opening it up to find a bill of $300.
All she could say to describe the situation was, “Ouch.”
In addition to the monthly expenses that come with the territory of owning a cell phone, buying a phone itself can be expensive too. While most wireless carriers offer free phones for signing up, the upper echelon sets, like the Samsung “i600 Smartphone” from Verizon Wireless that costs $549, can still strike a hit to the wallet.
While phones like this incorporate many added features like Microsoft Windows Mobile and can surf the internet, the result of owning one is carrying around a valuable piece of equipment at all times if one wants to make use of it. In situations like this, picking up an insurance plan can Giúp to ease the tension of handling such a high-priced device.
“Having insurance on my cell phone has been awesome because once my phone fell in the toilet bowl and stopped working, and a second time it was stolen,” said Northeastern sociology major Tara Doran. “With the insurance (each time) I was able to get replacement phones of the same model.”
In addition for use when on-the-run, another main reason people want to own a cell phone is in case of an emergency, according to a Nov. 1, 2004 Washington Post article.
“I am quite the scatterbrained fellow, and often lose my keys, etc. so when something along those lines happens, it is good to be able to call someone without the use of change, which one doesn't always have,” Yetter said.
Having a mobile phone when in a pinch or even when just simply going out can be a comforting aid, Yetter said. “What it all boils down to,” he said, is that as much as he doesn’t want to subscribe to a service he believes is a problem with America, he has to acknowledge that in many cases it is necessary to own one.
In today’s society, especially in the setting of a college campus, the need for each individual to own a cell phone has come to the point of it being personal information so closely identified with a person that it can be found as a separate field on various applications forms and profiles on internet sites. It is just simply necessary to have one these days as the pros will always outweigh the cons, said Baxter.
“You can get in touch with group members (for school projects) at anytime or call a friend when you’re just hanging around campus,” she said. “Having a cell phone is just plain very convenient."
Levin said that they just make sense the world today.
"Ten years ago, before cell phones and iPods, you would've thought someone was psychotic (for being) alone, muttering something under their breath or singing a tune," he said. "(They) just fit so well with our fast paced life and our inability to wait."
Lợi ích và tác hại của Điện thoại
Benefits And Problems Of Mobile Phones
The advent of mobile phones has squeezed this large world and brought it into the palm of human being. However mobile phones have always been instigating debates among the people about their merits and demerits. Apart from the instant access they give us, mobile phones have multipurpose uses ranging from business work, means for entertainment and ensuring security. On the other hand, they have some disadvantages like initiating violation of privacy, unnecessary wastage of money, talking on mobile phones while driving and emission of radiation from the handsets which is allegedly harmful for health. I would like to argue for the advantages of mobile phones which outweigh their disadvantages.
The main feature of mobile phones is instant access' which makes them the most exclusive devices for communication. Now people can make voice or VDO call or send text messages to anyone anytime from almost anywhere at a cheap rate using mobile phones. Besides this, with the aid of the latest WAP technology users can surf the internet, send emails and chat with other people at a low cost (Bấm vào đây để đăng nhập và xem link!, 24th October, 2007). According to a research released on 13th February, 2007 from the Mobile Entertainment Forum and Ovum, 20% of UK subscribers search internet via mobile phones (Bấm vào đây để đăng nhập và xem link!, retrieved 24th October, 2007). It is obvious that the communication has become a lot easier now compared to the pre-mobile phones period.
Mobile phones are lessening the pressure of the business and office work too. These days, the latest mobile phones are powered with Microsoft Office application for viewing and editing various types of files including Word, PDF, and Excel etc easing the office and business work (Markley, Bấm vào đây để đăng nhập và xem link!, retrieved 30th October, 2007). Moreover, in this modern world of advanced communication loads of business deals are made through mobile phone conferences.
Apart from these, mobile phones are widely used for entertainment replacing number of miniature gadgets by comprising all their features. Now most of the mobile phones include games, mp3 and mp4 players, high resolution digital camera, radio etc which are the main attraction of the young generation. (Gonsalves, 2006, Bấm vào đây để đăng nhập và xem link!, retrieved 25th October, 2007).
Mobiles phones are also giving their users security to some extent. People can call each other instantly for Giúp whenever they are in any danger or crisis. Even using GPS navigation technology in one's mobile phone one can find out his/her way if he/she is lost in the street (about.com, retrieved 26th October, 2007). Thus people tend to feel safe when they are carrying their mobile phone.
On the contrary, mobile phones have some demerits e.g. they violate privacy of people. Some people misuse their camera phones or voice recording option of phones to take secret pictures or record conversations which infringe other people's private life.
Another disadvantage of mobile phones is that they instigate wastage of money. Most of the teenagers now own mobile phones and a lot of them spend hours after hours talking unnecessarily on phone. This results in the payment of high bills which is a sheer waste of money.
Besides these, mobile phones may cause serious accident if somebody is talking on phone while driving and unmindful for even a fraction of a second. For instance, in the year 2005, a driver in Sheffield ran over an 80-year-old pedestrian while talking on mobile phone and was jailed for 2 years (telegraph.co.uk, retrieved 29th October, 2007).
Recently mobile phones are also accused of emitting radiation which is harmful for health causing cancer, brain tumours, headaches, sleeping disorders etc (Highfield, 2004, telegraph.co.uk). Researches are still being undertaken to come to a definite conclusion if there is any possible impairment by the radiation.
"Research by the Radiation and Nuclear Safety Authority in Finland found that microwaves from cell phone handsets damaged the blood-brain barrier, which prevents materials from the blood entering the brain. It warned that this might have implications for human health" (Uhlig, 2002, telegraph.co.uk).
But it does not insinuate that the biological effect may necessarily pose health risk. As Dr Michael Clarke argues:
"But we need to remember that all sorts of things - tea, caffeine, red wine, sugar - have biological effects without necessarily damaging health" (telegraph.co.uk, retrieved 31st October, 2007).
However precautionary approach can be taken to avoid any probable risk that may be caused by mobile phone radiation i.e. using earphones while talking on mobile. Besides this, all the mobile phone manufacturers are now producing mobiles with a limited SAR (Specific Absorption Ratio) limit which minimizes the impact of radiation (Markley, Bấm vào đây để đăng nhập và xem link!, retrieved 27th October, 2007).
Considering all the merits and demerits, I believe that the advantages of mobile phones outweigh their disadvantages. At the end of the day, it is we who use the mobile phones the way we want. So mobile phones should not be blamed for its misuses. They are the perfect emblems of the advancement of communication technology and play a vital role in this modern world of globalization. That is why we should ensure their best and most effective uses.
Positive Impact of Cell Phones
Cell phones have been found to have many benefits although there is some anxiety about their safety. We all know how cell phones can be annoying at times, but, they can be a great source of security. Many people have cell phones. They are so popular because they can be carried from place to place. Cellular phones were originally for cars only. Now that technology has evolved we are able to carry around small and compact phones. Some car phones are installed permanently in the car. The car phone would draw power from the vehicle's battery. Others are portable and powered by the car's cigarette lighter or by an internal rechargeable battery.
We are not certain if cell phones have a negative impact on driving safety. None of the experts dispute that finger dialing and hand-held phones momentarily distract drivers. The driver must have the ability to concentrate first and foremost on driving. Many argue that coffee mugs, CD players, radio-even car fax machines, and computers can cause equal or worse distractions for drivers. The question I how responsible is the individual behind the wheel. The risk of being involved in traffic accidents while using cell phones was nearly four times that of the average driver. Using a hands free phone is equally as hazardous as a normal cell phone. Also, it is hard to prove that using a cell phone is dangerous. Advances in technology have lad to voice recognition phones. These types of phones may be a helpful tool in making the roads safer. When the car phone first appeared, some police officials worried that drivers using them would not pay attention to the road and would get into accidents; In fact, the phones have slightly made roads safer. "The point," said Master Sgt. John Duley, of the Connecticut State Policy, "is to drive safely."
Cell phones are everywhere in the world, just look around. There are more than 50 million cell phone subscribers in the U.S. alone. In 1994, 16 million Americans subscribed to cell phone services. Today more than 110 million Americans are subscribers. By 2005, experts predict world-wide subscribers will reach 1.2 billion people. That many people with cell phones driving and talking at the same time will make there be less concentration on the road. Although in 1990, the AAA Foundation for traffic safety reported there is no evidence that the use of car phones poses a hazard to the motoring public. In 1997, the New England Journal of Medicine published perhaps the most thorough study of this issue to date. The study monitored approximately 700 cell phone users in Ontario, Canada during a 14-month period in 1994 and 1995. That study made the hands free law all the more controversial. Also, did you know cell phone users grew by 1685% and traffic accidents went down by 17% from 1985 to 1986?
I think having a cell phone gives you a peace of mind. Children with cell phones are more in touch with their parents. They know where they're at and what they are doing. Seventy-percent of people say they wanted cell phones for personal safety. Other than personal safety cell phones can also prevent crimes. It is also proven particularly useful to women driving alone. An example for personal safety is if I was somewhere and no one knew where I was, I could use a cell phone to get a ride or tell my location. That situation has happened to me before.
Cell phones can serve a useful purpose to police. In 1990, the highest report of emergency numbers was called to date. Every month people with car phones make around 600,000 calls. The cell phone has become a popular crime-fighting and safety tool for drivers. Because of technology's reliability, rescue workers increasingly trust it for communication during floods, hurricanes, earthquakes, and brush fires. Police officers use the phone when they need radio silence. Cellular pones are making roads safer particularly against drunk drivers. Using car phones to lasso drunks has become a nationwide pastime. In some states cars have an HP button installed. If you hit the HP button it instantly connects you to Highway Patrol. This feature helps people report drunks. The biggest use of cell phones is by reporting drunk drivers. In some states like Illinois, it offers $100 savings bond for every drunk arrested. More than 400 cellular owners have collected in the past four years.
Cell phones are complicated pieces of machinery. When you receive a call on your cell phone, the message travels through the telephone network until it reaches a base station close to your cell phone. Then it sends radio waves in your phone where it is charged to sound. Dialing a cell phone sends a radio signal to the cell phone company tower covering the geographic area, or cell site. The signal is switched to a land-line, and the call proceeds through the telephone wires. When a driver begins moving out of one cell site, a telephone company computer senses a weak signal and automatically passes the call to the next tower. There are about 13,000 towers in operation. Ninety-seven percent of the population lies within range of cellular service. That is a lot of people.
I think cell phones have had a positive impact on the world. Cell phones have made a lot of people feel safer. They have helped kids stay in touch with parents and have stopped many drunk drivers from causing harm. They have distracted us at times. When you are at a movie or in church or just in public in general, we have been annoyed and distracted by ringing cell phones. Even though we've all been distracted by the sound of ringing cell phones, they have come to serve a purpose.