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6 tháng 4 2021

Non-recoverable energy sources, such as coal, gas, have been exploited by humans for a long time . These kinds of energy take a very long time to form. However, its consumption happens so fast that it causes the problem of depletion of natural resources as well as pollution.

Meanwhile, renewable energy sources such as wind, solar, and water are available in abundance and availability. However, the exploitation of this energy source requires modern and complex equipment.

Renewable energy source promises to be the energy source of the future. They are friendly to the environment. We should make use of them and reduce the reliance on non-renewable resources.

 

Chúc em mai thi tốt nhé!

12 tháng 3 2022

tự suy nghĩ mak làm hoặc e tham khảo gg dịch nhé

đừng cóa lên đay nhờ ăn sẵn nx em cố gắng tự vt nha

18 tháng 3 2018

VỀ PHIM

The film I like best is Boy Hood.It's a school life film with the acting of Karry,Roy and Jackson.It's about school life and basketball competition between two schools.The film is very gripping and hilarious but it has a sad ending.The acting of the character is natural and exellent.The music,which is really suitable for this film and interesting with a fun rhythm.The visuals are beautiful with a lot of beautiful sceneries.Critics say that it is one of the best film with gripping and hilarious scenes.It also includes a meaningful message for the young.And,I think that is one of the best films I have ever-seen.It's a must-see film for everybody.

VỀ GIAO THÔNG

I think traffic in my city is bad and not strictly because there are many traffic problems.First,there are too many vehicles on the road.Also,m any cattle and dogs run along or across the road.Children play on it and some villagers sell and buy things,too.Second,many roads are narrow and bumpy.They are easily flooded when it rain so heavily.The roads roads become wet and slippery after the rain.The last,many people don't obey the traffic rules.They usually drive and ride very dangerously,so there are many traffic accidents everyday.In order to reduce these problems,we must strictly obey all the traffic rules

22 tháng 6 2020

According to me, learning English can definitely change your life . Nowadays, many families let their children to learn foreign language, espeacially is English . The main reason is beacause of social development . Also, in some universities, you need an English certificate to pass the exams . If you have a large knowledge of English , you can speak to people around the world or you can get a scholarship. English is very nescessary to our life. So how can we study English easily . You can watch English movies or some English songs, that might be very interesting. You can improve your pronounciation by downloading the app "Elsa speak " . If you are on another level, you can try to talk to some foriegners in some parks . Learning English is very important so remember to try your best in speaking as much as possible.

15 tháng 4 2021

   I am a volunteer so I have done many things for the community service. Last month, I raised money and funds for the poor, and they were very hapy. I also donated books and clothes for the children. Last week, I provided houses and food for the homless, and they looked very happy, too. So far, I , and my classmates, have planted trees and beautiful flowers in the school yard. It was so great. I have collected the rubbish on the beach and in the sea then I recycle them. It helps protectthe environment. And I, together with my family, often go to the hospital to help every one there. They are so freindly and they seem very happy when they see us. Volunteering is very good and special to me 'cause I can help others. I 'll do more in the future.

12 tháng 4 2022

tham khảo
With fast growth of civilization there is also an ever mounting need for energy. Energy may be in the form of fuels or electricity. Petrol is a liquid fuel which is used widely nowadays. But this kind of fuels is likely to be exhausted at the rate man is using it recently.

To meet the challenge, various methods have been suggested. One is to minimize the man’s demand in using the energy. Non-essential consumption should be minimized. During certain days of the year, people all over the world turn off the electricity for 1 hour to save the energy. Modern gadgets consuming energy should only be used when they are absolutely necessary.

Energy conservation is possible through modernization of plant and equipment. People should replace the obsolete equipment by the modern ones.

Energy can be saved on transport by the following methods. People should commute by the rail rather than by cars and vans. The transport must be improved with a view to sparing the energy. Cities must be planned in such a way that the commuting distance from this place to others is minimized.

In industry, many things could be done to reduce waste of energy or to economize energy. The machine maintenance needs to be tightened; heater must be utilized properly. When systems are streamlined, economy in fuel is obvious. Instead of using materials requiring higher energy, those which require lower energy should be used.

We hope man with his ever rising urge for existence will cope up with this urgent problem and find alternatives.

19 tháng 12 2017

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.”

Health Concerns
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.

Multitasking
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.”

Cost
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.”

Convenience
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."

Dalat Flower Festival is a cultural festival which takes place every other year in Da Lat city, Lam Dong, Vietnam and some other localities in Lamdong province. The festival is held with the purpose of exhibiting flowers, vegetables and ornamental plants from the local as well as other regions within the country and many other countries in the world in order to attract visitors to come to Dalat, promote economic development of the city. Dalat Flower Festival is also an activity honoring the value of flowers and floriculture, calling for investment in Dalat flower industry as well as promoting a positive image of the city, the culture and the people of Dalat.

19 tháng 3 2018

I attented Thuong Temple festival last month. It’s a seasonal festival in Lao Cai city. It is held on the 15 th of the first lunar month. Local people made offerings of incense to worship General Tran Hung Dao who defeated the Mongok 3 times. Besides, there were many activities such as: shpping, playing traditional games, singing, dancing, … Many local people and townritsfrom all over the country attented the festival. This is an occation for us to show our love to our motheland and preserve our cultural traditions.

21 tháng 3 2019

- Walk or ride a bike when travelling short distances

- Use some low energy light bulds

- Turn off the light when leave

- Don`t leave when the (Tủ lạnh) open

21 tháng 3 2019

Nowadays, energy is being run out more and more so it is one of the most important things of our life. We need to save energy because nobody of us can lives without energy. So why don't we start to do it right in our home? We have many ways to save energy in our home. One of those ways is using electricity, water and gas economically. Such as we should turn off the light in room when we go out or in unnecessary situations, avoid wasting water, shut the kitchen stove when stop cooking. Use a microwave instead of a stove to reheat food. Use rechargeable batteries instead of disposable batteries... Besides, we should use electrical equipments which are energy - saving. Such as using lights and fans that have low capacity, or using equipments which reserve electricty. Not only do these help us to save money but also they work effectively.
In addition, we should frequently check electrical equipments in our home in order to fix opportunely. In summary, we need to save energy so that energy isn't run out and continues to serve human's life.

25 tháng 12 2019

Bn tìm tranh về Ha Long Bay nhé!

Halong Bay is one of Mother Earth’s most amazing natural wonders and one of Vietnam’s most prized treasures.Halong Bay is formed by Cat Ba island to the South, Ngoc Hung and Van Canh islands to the East and the Vietnamese coastline to the North and West.

The most outstanding feature of Halong Bay and undoubtedly its greatest attraction are the 1,696 islands, islets and rocky karst outcrops. 989 of these islets and rocky outcrops have been been given imaginative names by the locals over the years. These have been derived from their perceived shapes and include names such as Man’s Head, Fighting Cocks, Wading Ox and Wallowing Buffalo.
With heights ranging from 50-100 meters (160-330 feet) and a height-to-width ratio of about 6:1, the majority of these karst pinnacles and islets have sheer, vertical cliffs. They are uninhabited and unaffected by human activities. The pure size and numbers of these outcrops provide a stunning contrast and backdrop to the turquoise waters of the bay when viewed from sea level. Another exceptional geological feature of Halong Bay is the number of limestone islands which have caves and grottoes within them. The total number of caves has never been determined and there are almost certainly more which are yet to be discovered. In order to preserve the natural state and integrity of the large number of caves and grottos in the World Heritage Area, only some are open to visitors. The most commonly visited are Thien Cung (Heavenly Palace) cave, Dau Go (Wood Tip) grotto, Sung Sot (Surprise) cave and Trinh Nu (Virgin) grotto.
The shapes and formations on the sides and rooves of the caves, many now being part of local folklore and legends, bear witness to the different stages of formation over the ages. Some cave features, such as calcified shell-beds, are the direct result of ancient human activity. The lower chambers of some caves and grottos are below sea level. Due to the porous nature of limestone, these chambers are often partially filled to form tidal lakes and pools. Although most of these are shallow, the depths of some have never been determined. The geomorphology of Halong Bay indicates that it is almost certain that there are undiscovered and fully entombed lakes within many of the islands. Dau Be (Goat’s Head island) alone has 6 different tidal lakes.
The sea in Halong Bay is generally less than 10 meters (33 feet) deep and boasts a rich biodiversity of about 1,000 species of marine animals. Over 160 species of coral have been identified. Coral reefs make up 30% of the seabed and in some areas as much as 80% of the seabed is covered in coral reefs. Most coral reefs are at a depth of 4-6 meters. Undoubtedly Halong Bay’s greatest attraction is its natural scenery. The towering limestone outcrops jutting skywards from the emerald-blue waters. The sheer numbers and size of the islands, islets and karsts within the bay serve to humble even the most jaded traveler.
Swimming, kayaking, hiking and of course photography are favorite pastimes for visitors to Halong Bay - one of the most popular tourist attractions in all of Vietnam. Abundant fresh local seafood is another delight.
Floating fishing villages are the most popular human attraction. Entire village populations live, work and die on these ’floating islands’ in Halong Bay. The villagers are mainly fisherfolk and ply the waters around their villages selling their fresh produce to the passing tourist trade.

25 tháng 12 2019

mai mik thi rồi giúp mik vs