Subordinate Routes

The general rule for route dominancy is: among all concurrent routes, the route with the lowest sign system code dominates. If more than one route shares the same lowest sign system code the one with the smallest route number dominates. Measures embedded in routes are derived by linear interpolation based on calibration point data collected by using a Distance Measuring Instrument (DMI) except for ramps which use the geometry length to derive measures. Collection of all Routes that are running concurrent with a dominant route layer as extracted from the Dominant Routes Layer in West Virginia. Current feature information included in this layer is the ROUTEID, Label, Sub Route, Sign System, Supplemental Code, Route Number, County Code, District, Beginning Mile Point, Ending Mile Points, Comments, Year Recorded and State Code. Data is in NAD_1983_UTM_Zone_17N projection. Data is updated semi-annually.线路主导性的通用规则为：在所有并行线路中，标识系统代码最低的线路具有主导权。若多条线路共享相同的最低标识系统代码，则线路编号最小的线路成为主导线路。 线路内嵌的度量属性，除匝道外均基于测距仪（Distance Measuring Instrument, DMI）采集的校准点数据，通过线性插值法计算得到；匝道则采用几何长度计算相关度量属性。 本数据集收录了从西弗吉尼亚州（West Virginia）主导线路图层（Dominant Routes Layer）中提取的、与该图层内主导线路并行的全部线路。 该图层当前包含的要素属性信息包括：ROUTEID、Label、Sub Route、Sign System、Supplemental Code、Route Number、County Code、District、Beginning Mile Point、Ending Mile Points、Comments、Year Recorded以及State Code。 数据采用NAD_1983_UTM_Zone_17N坐标系投影。 数据每半年更新一次。