in this paper a practical method for tropospheric effects on gps derived coordinates in absolute mode is presented. gps observations at the permanent gps stations can be used as source of information for the modeling. the developed model is a time-dependent model and as such differs from usual tropospheric models, which are based on atmospheric parameters, i.e. temperature, pressure and humidit...

Learning objects along with their sequencing are being studied to support efficient e-learning systems. They could solve the problem of costly reproduction of learning materials for e-learning systems. The problem arising here is related to the size and complexity of methods used to achieve the appropriate composition of learning objects in order to generate courses with pedagogic efficiency an...