The Japanese Quasi-Zenith Satellite System (QZSS) has been developed as a GPS (Global Positioning System) complementary system to improve positioning accuracy in the Asia-Pacific region. However. the accuracies of ultra-rapid predicted clocks are not high enough for real-time applications. so it is still a challenge problem. https://allfixelectricales.shop/product-category/oven-shelf-support-rack-screw/