Questions are based on the following passage.
Many of the most damaging and life threatening types of weather, such as torrential rains and severe thunderstorms, begin quickly, strike suddenly, and disappear rapidly, destroying small regions while leaving neighboring areas untoucheD.(79) Conventional (普通) computer models of the atmosphere have limited value in predicting short-lived local storms because the available weather data are generally not detailed enough to allow computers to see clearly the small atmospheric changes that come before these storms. In most nations, for example, weather-balloon observations are taken just once every twelve hours at location typically separated by hundreds of miles. With such limited data, conventional forecasting models do a much better job predicting general weather conditions over large regions than they do forecasting specific local events.
Until recently, the observation-intensive approach needed for accurate, very short range forecasts, or "nowcasts", was impracticable. The cost of equipping and operating many thousands of conventional weather stations was extremely high, and the difficulties involved in rapidly collecting and processing the raw weather data from such a network were beyond overcoming. Fortunately, scientific and technological advance have overcome most of these problems. Radar systems, automated weather instruments, and satellites are all capable of making detailed, nearly continuous observations over large regions at a relatively low cost. Communication satellites can transmit data around the world cheaply and immediately, and modem computers can quickly compile and analyze this large volume of weather information. (80) Meteorologists (气象学家) and computer scientists now work together to design computer programs and video equipment capable of transforming raw weather data into words, symbols, and vivid graphic displays that forecasters can interpret easily and quickly. As meteorologists have begun using these new technologies in weather forecasting offices, nowcasting is becoming a reality.
What is the best title of the passage? 查看材料
A.Severe Thunderstorms and Damages
B.Weather Forecasting and Life-threatening
C.Science Advances and Nowcasts
D.Available Data and Nowcasts
第3题
在实验过程中,给予动物某药物后出现心率减慢,心电图PR间期延长,该药是()。
A.阿托品
B.普萘洛尔
C.肾上腺素
D.去甲肾上腺素
E.酚妥拉明
第4题
A.主要表现为P-R间期延长
B.成人P-R间期≥0.21S
C.心率相同时P-R较前延长>0.04S
D.P-R间期随心率的快慢变化明显
E.P-R间期的长短不受年龄影响
第5题
A.心电图P-R间期缩短
B.心电图Q-T间期缩短
C.心电图Q-T间期延长
D.心电图P-R间期延长
E.心电图P-P(或R-R)间期延长
强心苷的负性频率作用可表现为()E.
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