We have collected an up-to-date sample of 123 superluminal sources （84 quasars, 27 BL Lac objects and 12 galaxies） and calculated the apparent velocities （βapp） for 224 components in the sources with the A-CDM mo...We have collected an up-to-date sample of 123 superluminal sources （84 quasars, 27 BL Lac objects and 12 galaxies） and calculated the apparent velocities （βapp） for 224 components in the sources with the A-CDM model. We checked the relationships between their proper motions, redshifts,βapp and 5 GHz flux densities. Our analysis shows that the radio emission is strongly boosted by the Doppler effect. The superluminal motion and the relativistic beaming boosting effect are, to some extent, the same in active galactic nuclei.展开更多
Active X数据对象 ( Active X Data Object,简称 ADO)是由微软公司推出的以 Active X技术为基础的一组基于 OL E DB数据的高级自动化应用层接口 ,是一种新型的数据访问方法。与微软以前提供的数据访问方法 DAO( Data Access Object)、RD...Active X数据对象 ( Active X Data Object,简称 ADO)是由微软公司推出的以 Active X技术为基础的一组基于 OL E DB数据的高级自动化应用层接口 ,是一种新型的数据访问方法。与微软以前提供的数据访问方法 DAO( Data Access Object)、RDO( Remote Data Object)相比 ,ADO的速度更快、使用更方便、内存占用更少 ,所以 ADO一推出便受到广大用户的青睐 ,成为数据访问技术的一个发展方向。本文介绍了 ADO的对象模型及其在 VB中实现数据访问的方法。展开更多
基金the NSFC(Grants 10573005 and 10633010)the 973 project(2007CB815405)
文摘We have collected an up-to-date sample of 123 superluminal sources （84 quasars, 27 BL Lac objects and 12 galaxies） and calculated the apparent velocities （βapp） for 224 components in the sources with the A-CDM model. We checked the relationships between their proper motions, redshifts,βapp and 5 GHz flux densities. Our analysis shows that the radio emission is strongly boosted by the Doppler effect. The superluminal motion and the relativistic beaming boosting effect are, to some extent, the same in active galactic nuclei.
文摘Active X数据对象 ( Active X Data Object,简称 ADO)是由微软公司推出的以 Active X技术为基础的一组基于 OL E DB数据的高级自动化应用层接口 ,是一种新型的数据访问方法。与微软以前提供的数据访问方法 DAO( Data Access Object)、RDO( Remote Data Object)相比 ,ADO的速度更快、使用更方便、内存占用更少 ,所以 ADO一推出便受到广大用户的青睐 ,成为数据访问技术的一个发展方向。本文介绍了 ADO的对象模型及其在 VB中实现数据访问的方法。
