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In our study, 48 U.S. departments that grant geography PhDs are compared along four measures of academic productivity. Using 1980–1994 as the base period, research productivity of faculty was assessed by counting book titles, as well as authorships in 77 journals. Teaching productivity was determined by placement of PhDs in graduate programs of geography in North America, and by a weighted index of teaching outcomes. Data were summed for departments, but are reported primarily as productivity per person (per FTE count). The results point to a wide variety of departmental profiles, from those departments that appear to emphasize teaching outcomes to those that are more productive in book publishing and journal authorship, with several exhibiting a balance between teaching and research.  相似文献   
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本文分析了2004年2月11日11:00~11:40 UT期间Cluster卫星簇的磁通门磁力计FGM)、等离子体电子及电流试验仪(PEACE)和CUTLASS 芬兰雷达对多个磁通量传输事件(FTEs)的同时观测. 在此期间,Cluster卫星簇位于北半球外极隙区附近,并于11:18 UT左右穿出磁层顶进入磁鞘,四颗卫星同时观测到了多个FTEs, 其出现具有准周期性,周期约为130 s. 利用Cluster四颗卫星的多点同时观测数据,采用最小方向微分法和时空微分方法,我们推断这些FTEs是尺度大小约为(0.87~1.81)RE的准二维结构,其运动方向为东北方向,与Cooling模型预测方向基本一致. CUTLASS芬兰雷达在相应的电离层区域观测到了明显的“极向运动雷达极光”结构,这些结构与Cluster卫星簇观测的FTEs有着很好的对应关系,它们是FTEs的雷达观测特征.  相似文献   
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2004-03-18 23:10~23:50 UT期间,“双星(Double Star)”探测一号卫星(TC 1)在向阳面磁层顶高纬晨侧由内向外穿越磁层顶,其时TC_1的GSM坐标为 (75RE, -55RE, -54RE), RE为地球半径.穿越过程中TC_1观测到了8个通量管和1个磁通量传输事件(FTEs).在此期间Cluster星簇位于向阳面太阳风内,其GSM坐标为(180RE, -31RE, -62RE),其4颗卫星监测到行星际磁场(IMF)的BZ分量持续南向,BY有较大的负值.本文的研究表明:TC_1观测到的前7个通量管具有准周期重现性,周期大约是1~4 min,明显小于以前所观测到的FTEs的平均周期(8~11 min);所有的通量管都具有较强的核心场.本文分别使用最小方差分析法(MVA)和Grad_Shafranov反演方法(GSR)对通量管的轴向进行了分析和对比,发现所有的通量管主轴基本沿晨昏向,结果显示GSR方法在轴向分析上比MVA优越.本文使用GSR方法对通量管的磁场结构进行了分析,恢复出了通量管的磁场在卫星穿越面的结构图;此外,本文还对这次多重通量管事件进行了deHoffmann Teller(HT)分析,结果表明,所有通量管大致朝南极方向运动,均来源于向日面低纬区域.这说明它们可能起源于向日面低纬区,由该区的磁场分量重联产生.  相似文献   
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In our study, 48 U.S. departments that grant geography PhDs are compared along four measures of academic productivity. Using 1980–1994 as the base period, research productivity of faculty was assessed by counting book titles, as well as authorships in 77 journals. Teaching productivity was determined by placement of PhDs in graduate programs of geography in North America, and by a weighted index of teaching outcomes. Data were summed for departments, but are reported primarily as productivity per person (per FTE count). The results point to a wide variety of departmental profiles, from those departments that appear to emphasize teaching outcomes to those that are more productive in book publishing and journal authorship, with several exhibiting a balance between teaching and research.  相似文献   
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