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51.
随着高新技术的发展,人力资源管理已成为影响高校图书馆建设与发展的重要因素。本文分析了高校图书馆人力资源管理中出现的误区,并从五个方面探讨了改善当前高校图书馆人力资源管理现状的对策和方法。  相似文献   
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The ability to locate and characterize icy deposits and other hydrogenous materials on the Moon and Mars will help us understand the distribution of water and, therefore, possible habitats at Mars, and may help us locate primitive prebiotic compounds at the Moon's poles. We have developed a rover-borne neutron probe that localizes a near-surface icy deposit and provides information about its burial depth and abundance. We have also developed a borehole neutron probe to determine the stratigraphy of hydrogenous subsurface layers while operating within a drill string segment. In our field tests, we have used a neutron source to "illuminate" surrounding materials and gauge the instruments' efficacy, and we can simulate accurately the observed instrument responses using a Monte Carlo nuclear transport code (MCNPX). An active neutron source would not be needed for lunar or martian near-surface exploration: cosmic-ray interactions provide sufficient neutron flux to depths of several meters and yield better depth and abundance sensitivity than an active source. However, for deep drilling (>or=10 m depth), a source is required. We also present initial tests of a borehole gamma ray lithodensity tool and demonstrate its utility in determining soil or rock densities and composition.  相似文献   
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Morphologically diverse structures that may constitute organic microfossils are reported from three remote and widely separated localities assigned to the ca. 3400?Ma Strelley Pool Formation in the Pilbara Craton, Western Australia. These localities include the Panorama, Warralong, and Goldsworthy greenstone belts. From the Panorama greenstone belt, large (> 40?μm) lenticular to spindle-like structures, spheroidal structures, and mat-forming thread-like structures are found. Similar assemblages of carbonaceous structures have been identified from the Warralong and Goldsworthy greenstone belts, though these assemblages lack the thread-like structures but contain film-like structures. All structures are syngenetic with their host sedimentary black chert, which is associated with stromatolites and evaporites. The host chert is considered to have been deposited in a shallow water environment. Rigorous assessment of biogenicity (considering composition, size range, abundance, taphonomic features, and spatial distributions) suggests that cluster-forming small (<15 μm) spheroids, lenticular to spindle-like structures, and film-like structures with small spheroids are probable microfossils. Thread-like structures are more likely fossilized fibrils of biofilm, rather than microfossils. The biogenicity of solitary large (>15?μm) spheroids and simple film-like structures is less certain. Although further investigations are required to confirm the biogenicity of carbonaceous structures from the Strelley Pool Formation, this study presents evidence for the existence of morphologically complex and large microfossils at 3400?Ma in the Pilbara Craton, which can be correlated to the contemporaneous, possible microfossils reported from South Africa. Although there is still much to be learned, they should provide us with new insights into the early evolution of life and shallow water ecosystems.  相似文献   
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人类航天活动日益频繁,空间目标种类和数量不断增多,识别未知空间目标的关键特征具有重要的科学价值。本文通过辅助图形软件建模分割,获取球体、圆锥体和圆柱体带法向量的面元坐标;基于卫星仿真工具包,得到了目标轨道及位置参数,并结合双向反射分布函数各向异性Phong 模型和四元数姿态更新模型,完成了地基观测条件下4种形状空间目标的视星等仿真。仿真结果表明,目标受空间位置、形状和姿态的影响程度不同,其光度曲线具有各自特点。球体由于形状完全中心对称,光度曲线主要受空间位置的影响;圆锥体、正方体、圆柱体光度曲线的波形受形状影响较大,曲线走向受位置影响较大,波动频率受姿态角速率影响较大。通过统计分析相关数据,可为后续空间目标位置、姿态和形状的反演提供先验模型。   相似文献   
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