科學(xué)60秒:黑匣子為安全降落保駕護(hù)航
The little black boxes in airplanes provide useful information after a crash has taken place. Now researchers have___1___a way to use black box info from planes that do not___2___—to help preven
科學(xué)60秒:棒球裁判與數(shù)學(xué)結(jié)緣
The traveling salesman problem is a favorite math conundrum: if a salesman has to visit a ____1____ of cities, how do you get him to all of them once via the shortest possible route. But the trav...
自然與環(huán)境:亞特蘭大燃?xì)饩o缺
自然與環(huán)境:亞特蘭大燃?xì)饩o缺It has been a wild gas chase for a lot of people in Atlanta. A pump without a plastic bag on the handle or a “No Gas” sign is hard to come by thanks to supply issues...
晨讀美文071
聽寫時(shí)忽略標(biāo)題A young man sees a sunset and, unable to understand or to express the emotion that it rouses in him, concludes that it must be the gateway to a world that lies beyond. It is difficu...