题型：阅读理解 题类：模拟题 难易度：普通
河南省新乡市2018届高三英语第二次模拟考试试卷
There is a breakthrough in building aircrafts. Bendable wings covered with overlapping(部分重叠) pieces resembling fish sizes could be used to build swifter, fuel-efficient aircraft, a new study finds.
Nowadays, conventional aircrafts typically rely on ailerons (副翼) to help control the way the planes tip as they fly. However, when the Wright brothers flew the first airplane, Flyer 1, over a century ago, they used no ailerons but wires and pulleys that twisted the wood-and-canvas wings, to control the plane.
Scientists have long sought to develop aircrafts that can alter their wings during flight, just as birds can. However, most previous attempts have failed because they relied on heavy mechanical control structures within the wings. These structures were also complex and unreliable, said Neil Gershenfeld, a physicist and director of the Center for Bits and Atoms at Massachusetts Institute of Technology (MIT).
The new wing consists of a system of tiny, strong, lightweight modules. The shape of the wing can be changed uniformly along its length using two small motors, which apply a twisting pressure to each wingtip. These wings are covered in “skins” of overlapping strips of flexible material resembling fish sizes. These strips move across each other as the wings alter, providing a smooth outer surface, the researchers explained.
Wind-tunnel tests of these wings showed that they at least matched the aerodynamic properties of conventional wings, at about one-tenth the weight. Initial tests using remotely piloted aircrafts made with these wings have shown great promise, said Benjamin Jenett, a graduate student at the Center for Bits and Atoms at MIT.
The new modular structures the scientists developed could be manufactured quickly in mass quantities and then installed by teams of small robots. These modular structures also can be disassembled more easily, making repairs simpler.
“Still, the first aircraft built using this strategy will not be a passenger jet, ”Gershenfeld said. “Instead, the technology will likely first be tested on unmanned aircraft, leading to drones (无人机) that can fly for a long time, to help deliver internet access or medicine to remote villages and do some rescue works.”
Courses & Curriculum of the College of Arts & Sciences in Cornell
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The diversity of the courses you can take in the College of Arts & Sciences is extraordinary: Academic Distribution Requirements The College's academic distribution requirements will include: effective writing foreign language beyond the introductory level imaginative and critical thinking To choose your courses for a semester, use the Class Roster. It shows the schedule of all classes offered in a particular term, along with class enrollment information and course details. The Class Roster is updated frequently. To plan your classes over your four years at Cornell, use the Courses of Study. It represents Cornell's full catalog of courses and is published annually. It provides information on Cornell degree programs, requirements, policies and procedures. If you need help, call 607-255-5004 for an appointment with an advising dean. Or contact a career counselor in the Arts & Sciences Career Development Center at 607-255-4166 to talk about your interests and how they can translate into a major and a future career. A New Curriculum On October 30, 2018, the College of Arts & Sciences faculty（教员） approved a new undergraduate curriculum to be carried out over the next two to three years. The new curriculum focuses on the theme of exploration and reaffirms the college's commitment to a liberal arts and sciences education. Students who have questions about the new curriculum can view the approved proposal on the Course Designer app of Cornell. Innovative Learning If you're one of the 3,000 students across the university taking biology or physics at the College, you may be part of an innovative（创新的） classroom project that uses active learning, a new model that is proving to be the quickest path to expert-level mastery. Your education at Cornell will extend far beyond the classroom. You can join a faculty member's research team on campus, conduct field study research in different states or spend a semester with Cornell in Washington D.C. You could study abroad in one of more than 85 countries or develop your own research project through independent study. Give yourself the freedom to explore. |
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