【填空题】在实际使用中，常采用两个相同的传感器线圈共用一个衔铁，构成 电感传感器。测量时，衔铁通过导杆与被测位移量相连，当被测体移动时，导杆带动衔铁也以相同的位移上下移动，使两个磁回路中磁阻发生 相等， 相反的变化，导致一个线圈的电感量增加，另一个线圈的电感量减小。

【填空题】求图中电压uab=( )。

【填空题】Lesson 15 Listening Comprehension-2 Listen and Fill in the blanks with what you have heard On the benefits of ADSB The world aviation continues to evolve towards 1 to improve safety, communication, surveillance and navigation by extending the protection of 1090 megahertz frequency to satellites. Significant 2 can be made that will have an immediate impact as early as in 2017. since 1940s, radar has been the primary method to 3 and it remains so until today. In recent years ADSB has become a widely accepted 4 providing critical information to stakeholders. Current systems are limited to land-based areas leaving 70% of the world uncovered, creating 5 routing over much of the world’s airspace. These global blind spots will soon be disappear in 2017. ADSB receivers on satellites will 6 from all ADSB-equipped aircraft to ATC worldwide. This will provide near 7 of ADSB-equipped aircraft in any flight information region, including currently unsurveiled oceanic, polar, desert, and 8 Space-based ADSB will enable 9 , increase operational 10 for airlines, lower emissions, expand ATM efficiency and capacity and significantly enhance safety all with little 11

【填空题】Lesson 3 Listening Comprehension Blank-filling 2 We will begin by explaining the layout of a typical airport. Although airports are different in size and layout，airport markings and procedures have been 1 for safety and efficiency of operations so that everyone can comfortably and safely 2 on the ground. When an airport is built the runways are laid out so that the approaches to the runways avoid higher 3 and 4 , and the primary runway is aligned as much as possible with the commonly 5 . Any 6 runways are for use when the winds are from other directions. Generally pilots try to utilize the runway with the most direct 7 which minimizes the runway distance required also reduces their workload. The 8 width, strength and number of runways will be determined by the amount and the size of traffic expected. Many airports started out small and were 9 as use increased. Airport Landing services can be asphalt, 10 , grass, gravel or for sea planes water. Airports will also have taxiways and parking areas known as 11 . As airports increase in size and usage they become hosts to aviation businesses that provide fueling service, 12 , flight training, passenger and 13 service, manufacturing and other related services. When operating from a towered airport air traffic control or ATC will 14 arrivals and departures by issuing instructions and 15 to the pilots. When operating from a non-towered airport the pilots coordinate their own movements and use recommended patterns and procedures for safety and efficiency.

【填空题】Lesson 3 Listening Comprehension Blank-filling Passage One On January fifteenth, US Airways flight fifteen forty-nine was leaving La Guardia airport near New York City. Everything seemed normal and the weather was good that day. But as the 1 climbed to about 2 in the air, something happened. Captain Chesley Sullenberger reported that both of his plane's engines had 3 . The engines soon 4 . The plane was unable to 5 to the airport. So Captain Sullenberger made a quick decision to land the plane on the 6 of the nearby Hudson River. The emergency landing was 7 perfectly. Captain Sullenberger's actions saved the lives of one hundred fifty-five passengers and crew. But the 8 brought attention to a real and growing threat to 9 . Bird strikes happen all over the world. And they are not 10 . Bird Strike Committee USA says bird strikes cause about 600 million dollars in damage to American 11 and 12 aviation each year. The group says fifty-six thousand incidents were reported to the F.A.A. between 1999 and 2004. More than 7,600 bird and other 13 were reported for civilian aircraft in two thousand seven. But studies show only about 14 of bird strikes to civilian aircraft are reported. These incidents can be 15 . The organization says wildlife strikes have led to the deaths of 219 people around the world since 1988.

【填空题】Lesson 2 Listening Comprehension Blank-filling passage One Listening to the recording again and fill in the blanks with words you have heard. The wings _____1)_______ the airplane in the air, so it’s a good idea to have two wings. They also contain _____2)_______. Now the Skyhawk has a high wing, meaning that it is ____3)_______the airplane. A high wing has many advantages. The fuel tank _____4)_______are much easier to _____5)_______when checking fuel samples. You have much better ground clearance from low _____6)_______. You have an excellent view down and to the sides. During loading and unloading, you’ll really appreciate the _____7)_______the wing provides when it’s raining. The wing also provides _____8)_______ from the sun both on the ground and in the air. Listening to the recording again and fill in the blanks with words you have heard. The landing gear is another important part attached to the _____9)_______. Now the Skyhawk has, what is known as a_____10)_______, because it has one wheel in the front, that is called nose wheel, and two main wheels behind under the middle of the fuselage, a _____11)_______ like a triangle. The nose wheel _____12)_______ the airplane on the ground and supports the nose of the plane and the engine. The nose wheel does not have a _____13)_______ and is not as strong as main wheels. You don’t want to have a nose wheel supporting the full weight of the airplane. The nose wheel is connected through _____14)_______ to the _____15)_______located in the cockpit. If you _____16)_______ the left rudder pedal, the nose wheel turns to the left, pushing the right rudder pedal, turns the nose wheel to the right. The two main wheels are _____17)_______ to carry the full weight of the airplane by themselves. They’re normally the last to leave the ground during taking off and the first to touch during landing. The brakes are on the main wheels. You control each one _____18)_______ by pushing on the top of the rudder pedals.