Scientists say they have developed a system that uses machine learning to predict when and where lightning will strike. Researchers report the system is able to predict lightning strikes up to 30 minutes before they happen within a 30-kilometer area.
Lightning is a strong burst of electricity in the atmosphere. Since it carries an extremely powerful electrical charge, it can be destructive and deadly. European researchers have estimated that between 6,000 and 24,000 people are killed by lightning worldwide each year. For this reason, climate scientists have long sought to develop methods to predict lightning.
The system tested in the experiments uses a combination of data from weather stations and machine learning methods. The researchers developed a prediction model that was trained to recognize weather conditions that were likely to cause lightning.
The model was created with data collected over a 12-year period from 12 Swiss weather stations in cities and mountain areas. The data, related to four main surface conditions: air pressure, air temperature, relative humidity and wind speed, was placed into a unique machine learning algorithm (算法), which compared it to records of lightning strikes. Researchers say the algorithm was then able to learn the conditions under which lightning happens.
The researchers test-ran the system several times. They found that the system made predictions that proved correct almost 80 percent of the time. “It can now be used anywhere,” the Swiss Federal Institute of Technology said in a statement.
The researchers plan to keep developing the technology in partnership with a European effort that aims to create a lightning protection program. The effort is called the European Laser Lightning Rod project. Scientists working on the project are experimenting with a laser technology that could someday control lightning activity, transferring lightning charges from clouds to the ground. They hope that such technology can one day be used as protection against lightning strikes. Possible uses could be at stations, airports or places where large crowds gather.
1.Why was the system developed?
A.To meet kids’ curiosity about lightning.
B.To show the power of lightning.
C.To keep track of lightning deaths.
D.To protect people from lightning.
2.What is special about the system?
A.It was based on a number of samples worldwide.
B.It adopted a different machine learning algorithm.
C.It used an effective method of collecting data.
D.It required low cost of predicting lightning.
3.What will the researchers do next with the laser technology?
A.Monitor lightning activity. B.Prevent the occurrence of lightning.
C.Direct energy from lightning. D.Generate electricity with lightning.
4.What can be a suitable title for the text?
A.A System of Controlling Lightning B.A Method of Forecasting Lightning
C.A Theory of Employing Lightning D.A Model of Creating Lightning
The worst outbreak of desert locusts (蝗虫) in decades is presently underway in the Horn of Africa. It is the biggest of its kind in 25 years for Ethiopia and Somalia — and the worst Kenya has seen for 70 years.
What we are seeing in East Africa today is unlike anything we’ve seen in a very long time. Its destructive potential is enormous, and it’s taking place in a region where farmers need every gram of food to feed themselves and their families. Most of the countries hardest hit are those where millions of people are already vulnerable (脆弱的) or in serious humanitarian need, as they endure the impact of violence, drought, and floods.
We have acted quickly to respond to this outbreak. The primary method of battling locusts is the aerial spraying of pesticides (杀虫剂). FAO’s “Locust Watch” service explains that “although giant nets, flamethrowers, lasers, and huge vacuums have been proposed in the past, these are not in use for locust control. People and birds often eat locusts but usually not enough to significantly reduce population levels over large areas.”
The UN’s Office for the Coordination of Humanitarian Affairs has released $10 million from its Central Emergency Relief Fund to fund a huge scale-up in aerial operations to manage the outbreak.
But the window to contain this crisis is closing fast. We only have until the beginning of March to bring this infestation under control as that is when the rain and planting season begins. If left unchecked — and with expected additional rains — locust numbers in East Africa could increase 500 times by June.
We must act now to avoid a full-blown catastrophe. And we will. At the same time, we need to pay attention to a bigger picture. This is not the first time the Greater Horn of Africa has seen locust outbreak approach this scale, but the current situation is the worst in decades. This is linked to climate change. Warmer seas mean more tropical storms, generating the perfect breeding conditions for locusts.
1.What is implied in paragraph 2?
A.People in East Africa are suffering drought.
B.People in East Africa are going through floods.
C.The locust outbreak will cause crop failure.
D.The locust outbreak is worsening locals’ life.
2.What can we learn from the last paragraph?
A.We need a bigger picture to study the disaster.
B.It is the second outbreak of locusts in East Africa.
C.It is the largest outbreak of locusts ever in history.
D.The outbreak of locusts is fueled by global warming.
3.What is the purpose of the text?
A.To analyse and compare. B.To inform and call for.
C.To argue and discuss. D.To introduce and assess.
4.Where does the text probably come from?
A.A guidebook. B.A health magazine.
C.A news report. D.A chemistry paper.
Growing up, Deka Ismail says she let labels define what she could be. “I was a black girl, from a refugee (难民) family,” Deka said. “It was as if I was only allowed to explore in this predetermined box”
After a high school chemistry class inspired her to think about a career in science and gave her confidence in the field, Deka learned to live outside labels and began making big plans for her future. Now she is about to begin her freshman year at the University of California, planning to become a professor.
Born and raised in San Diego’s City Heights neighborhood, Deka is the daughter of a Somali refugee couple. When Deka was eight years old, her mother got a job by studying hard back in school in order to support the whole family. That made Deka realize that education could make a difference to one's life. She spent a lot of time in the library reading books, and didn’t do many of the things her peers did, like partying or having romantic relationships.
“I always felt like I had to be the perfect girl for my family,” Deka said. “You have to do your best and do much better than everyone else. I felt like the whole world was waiting for me to mess up.”
Deka’s efforts paid off. The summer before her senior year of high school, she was accepted to the American Chemical Society Project SEED Programme. “She brought both enthusiasm and focus,” Botham, a researcher at this research institute, recalled. “She arrived every day ready to work, ready to learn and ready to tackle new challenges regardless of whether or not she had done anything similar.”
When asked what advice she would give to others like her, Deka warned them not to underestimate themselves. “Don’t tell yourself that scholarship is too big or this programme is too competitive or I’ll never get into this school,” she said. “I was not sure whether I could make it until I started seeing the acceptance letters rolling in.”
1.From the passage, we can learn that ______.
A.Deka was adopted by a refugee family
B.Deka became a professor after graduation
C.Deka’s experiences drove her to work hard
D.Deka spent a lot of time going to parties
2.Deka realized the importance of education ______.
A.after her chemistry class B.from her mother’s experience
C.by reading books in the library D.through working at the institute
3.According to the last paragraph, Deka advised that students be ______.
A.patient B.ambitious
C.confident D.generous
4.What does the story intend to tell us?
A.Life is not all roses. B.Practice makes perfect.
C.Well begun is half done. D.Hard work leads to success.
Just as John Lubbock said, we may sit in a library and yet be in all quarters of the earth. Here are some of the coolest libraries of the world.
Stuttgart City Library
Despite a classic white-on-white color, Stuttgart City Library is one of the most visually appealing modern libraries. The amazing modem and simple look is the product of the Korean architect Yi Eun-young. The German library opened in 2011, and cost nearly 80 million euros to construct.
Kanazawa Umimirai Library
Architects from the Coelacanth K&H Architects studio designed the Kanazawa Umimirai Library lo create the best reading environment. Healed floors, an outpouring of natural light, and other features were specifically included lo achieve this goal. The wall, which consists of thousands of tiny openings, allows natural lighting into the building, improving the overall feel of the space. This Japanese library was opened in 2011, and reflects the appearance of many modem and simple spaces.
Library of Congress
In 1800, Congress set up the Library of Congress in Washington D.C.. Fifteen years later, Thomas Jefferson offered his personal library to replace books that were lost when the British set the building on fire in 1814. His books, which took nearly 50 years to collect, varied from texts on science, literature and philosophy, to books in a variety of foreign languages. These days, the Library of Congress offers more than 155 million items and the largest rare book collection in North America.
State Library of Victoria
The Slate Library of Victoria, located in Melbourne, Australia, is one of the largest exhibiting libraries in the world. Though it opened in 1856, major repairs took place between 1990 and 2004. The La Trobe Reading Room is one of the library’s main attractions due to its visually amazing architecture. The lawn at the library’s front attracts hundreds of city folk each day, who gather for lunch or to enjoy the statues there. The library currently contains over two million books, as well as armor (盔甲) of Ned Kelly, a folk hero against the ruling class.
1.Which library has the longest history?
A.Stuttgart City Library. B.Kanazawa Umimirai Library.
C.Library of Congress. D.State Library of Victoria.
2.What’s special about Stale Library of Victoria?
A.It has great architecture.
B.It has a folk hero’s statue in it.
C.It is the world’s largest exhibiting library.
D.It serves as a meeting place for the citizens.
3.What does the first two libraries have in common?
A.They are constructed in the modem style.
B.They cost a large amount of money.
C.They are designed by Korean architects.
D.They feature providing readers with natural light.
假设你是李华，你的美国朋友Tim想在寒假时到中国北京旅游，于是发邮件向你征求建议。请你回复一封邮件，内容包括：
1. 推荐北京这个城市；
2. 给出推荐理由；
3. 要提及喝茶。
注意：1.词数100左右；
2.可以适当增加细节，以使行文连贯。
3. 参考词汇：Tiananmen Squsre ; the Great Wall; the Summer Palace
Dear Tim,
______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Yours sincerely,
Li Hua
假定英语课上老师要求同桌之间交换修改作文,请你修改你同桌写的以下作文。文中共有10处语言错误,每句中最多有两处。每处错误仅涉及一个单词的增加、删除或修改。
增加:在缺词处加一个漏字符号(∧),并在其下面写出该加的词。
删除:把多余的词用斜线()划掉。
修改:在错的词下划一横线,并在该词下面写出修改后的词。
注意:1.每处错误及其修改均仅限一词;
2.只允许修改10处,多者(从第11处起)不计分。
Dear friends,
We'd like to share our culture , the art of Chinese Calligraphy (书法), with you. As you can see it, all the Chinese characters here are writing with the Four Treasures of the Study(文房四宝). Known for essential tools to create art works, they enjoy a long history and a good reputation. For Chinese, calligraphy served the purpose of conveying thought and showing the beauty of the lines. Writing Chinese characters are a practical and unique art, which can help make our souls pure.
Under guidance of our club members, you can taste the brilliant traditionally Chinese culture. If you are interesting, sign up to feel the beauty, elegance or power of writing. Looking forward to your participation!
