Structure electronic design of a crystal filter for high accuracy multi-mode crystal oscillator

Modern communication systems have a strong need for low-cost and high-stability frequency references. Although low-cost crystal oscillators can easily be realized and are available to the market in large quantities, crystal oscillators with frequency stability in the ppb(10^{-9}) range over a wide temperature range are only available at high...

Improving the Algal Bloom Prediction on the North Sea by Dual Ensemble Kalman Filter in GEM Model

Increasingly, the phytoplankton blooms (algal blooms) become a public health concern and a worldwide ecological problem. The Generic ecological model (GEM) plays a very important role to assess ecological quality of the Dutch coastal waters and the southern North Sea. Algal blooms can also be predicted by the GEM model mainly through chlorophyll...