求翻译：摘要：近年来北京城市公共交通的车辆结构优化调整，增加各种新能源车辆，发展绿色公共交通出行，减少城市交通污染排放，尤其是纯电动公交车的运用和推广，为北京公交出行和减少能耗和碳排放提供很好的示范。本文在电池安全条件下，对电池更换慢充模式和充电桩快充两种纯电动公交车运营技术条件和首末站充电站占地等主要指标测算和纯电动公交车开行条件和电动公交车备用电池等关键参数技术经济分析，为城市电动公交线开行方案和运营调度提供参考和基础数据依据。是什么意思？

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Summary: In recent years the Beijing urban public transportation vehicles optimizing the structure adjustment, increasing the range of new energy vehicles and develop green public transport and reducing urban transport emissions, especially pure electric buses and widespread use of for Beijing to ha

Abstract: In recent years the Beijing city mass transit vehicles structure optimization adjustment, increased each kind of new energy vehicles, the development green mass transit journey, reduced the municipal transportation pollution emissions, in particular the pure electrically operated public tr

Abstract: the urban public transport fleet structure optimization adjustment in Beijing, added a variety of new energy vehicles, developing green public transportation to reduce urban traffic pollution emissions, especially the use of electric buses and promotion, for Beijing's public transit and re

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