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我国公安机关是专门掌管社会治安、行使国家治安和刑事管理权的机关，这是公安机关与其他国家行政机关的不同之处。 ()
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违反治安管理的行为属于行政违法行为，犯罪行为是刑事违法行为。 ()
地方自治制警政管理体制以法国为代表。 ()
听力原文： The interpretation of dreams has been a favorite activity of people for as long as we have had recorded history. Some of these dream interprets have become famous, and some, like the European psychologist Sigmund Freud, felt that all dreams have meanings which relate to our personal relationships with family members and friends.
Good dreams include those in which we see 6urselves succeeding in some difficult or pleasant activity such as singing, dancing, talking with our friends, or experiencing the happiness which may not occur in our waking hours. Many persons report dreams of competing in athletic competitions or music competitions. The performance in these events can go beyond anything we might experience in reality. Who among us has not dreamed of spending pleasant hours with our real or imaginary lover, enjoying his or her company in ways known only to those who have loved？ Interpreters of such dreams give varied meanings, most of which are probably not very reliable. But, we often a wake from good dreams in a good mood, rested and ready to face the day.
Bad or unpleasant dreams include those which frighten us, recall unpleasant experiences from our lives, or present problems for which there is no evident solution. Dreams of failing an exam at school, dreams of losing a job or a good friend, dreams of accidents or death of a loved one in our family, etc. are unsettling and not easily understood. Some dream experts believe these dreams are now a threatening way to face a problem from real life. They give us a way to deal with the problem so that we may find it less stressful in our waking hours.
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Section B
Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D. You should decide on the best choice.
How would you design an aircraft if your main aim were to keep its roar from waking up the entire neighbor hood during takeoffs and landings？ A group of 40 engineers from the Massachusetts Institute of Technology and England's University of Cambridge took on that challenge and, three years later, has unveiled designs for the SAX 40. Thanks to a host of noise-silencing innovations, the 215-seat airplane should be virtually inaudible outside the airport. Designers estimate that the aircraft will emit just 63 decibels(分贝) at takeoff, about as loud as an average conversation, while Today's airliners hit up to 150 decibels. However, when landing, it still is noisier than at take off, about 100 decibels.
To achieve such relative silence, researchers needed to rethink' nearly every aspect of the typical airliner. "There's no one thing you can do," says Will Graham, who headed up the Cambridge airframe-design team. "You have to treat all the noise sources."
What aspects should be considered？ First, the long exhaust tubes have acoustic liners to get rid of noise, and the size of the exhaust nozzles can be made smaller during takeoff to reduce noise or larger while cruising for fuel efficiency. Second, instead of noisy flaps, a sloped wing and steep landing angle do the braking. Engines embedded in the frame, with air intakes an top, reduce drag and noise. Last, three radial-blade(径向叶片) fans per turbine move large volumes of air at low,quiet speeds. Precisely tuned turbine blades don't vibrate nonmoving parts.
Moreover, chief among the aspects is the airframe. The faster a plane flies, the louder it mars. So Graham and his group designed the SAX-40 with a blended-wing body, a concept that discard the tube-and-wing approach for a tailless, triangular structure. That shape provides extra lift, enabling the plane to fly more slowly during takeoffs and landings. It also saves a significant amount of fuel, getting some 35 percent more passenger-miles per gallon than a Boeing 777.
A number of other researchers are working on similar concepts. But challenges remain. An aircraft without a stabilizing tail would be far more difficult to fly. And then there is the question of how to make its flattened fuselage(机身) as structurally strong as a cylinder. But perhaps the biggest difficulty is the airline industry's financial in vestment in conservative design. Betting on such a radical plane, Graham says," would be a huge step for manufacturers."
What will be achieved by the design of SAX 40？
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