The present paper aims to provide a brief review on several deterministic ensemble Kalman filtering (EnKF) methods and the related practical techniques to prevent filter divergence. Since Evensen (1994), several formulations of EnKF have been proposed, and Whitaker and Hamill (2002) suggested that a deterministic method, a.k.a. an ensemble square root filter (EnSRF, Andrews 1968), is expected t...

The present paper aims to provide a brief review on several deterministic ensemble Kalman filtering (EnKF) methods and the related practical techniques to prevent filter divergence. Since Evensen (1994), several formulations of EnKF have been proposed, and Whitaker and Hamill (2002) suggested that a deterministic method, a.k.a. an ensemble square root filter (EnSRF, Andrews 1968), is expected t...

We consider short-range (1-3-km) free-space optical communication between moving parties when covertness is the overriding system performance requirement. To maximize covertness, it is critical to minimize the time required for the acquisition phase, during which the party initiating contact must conduct a broad-field scan and so risks revealing his position. Assuming an elliptical Gaussian bea...

The dynamical core of an atmospheric general circulation model is engineered to satisfy a delicate balance between numerical stability, computational cost, and an accurate representation of the equations of motion. It generally contains either explicitly added or inherent numerical diffusion mechanisms to control the buildup of energy or enstrophy at the smallest scales. The diffusion fosters c...

Srivastava and Maheshwari (Iranian Journal of Fuzzy Systems 13(1)(2016) 25-44) introduced a new divergence measure for intuitionisticfuzzy sets (IFSs). The properties of the proposed divergence measurewere studied and the efficiency of the proposed divergence measurein the context of medical diagnosis was also demonstrated. In thisnote, we point out some errors in ...

The response of the monsoonal and annual-meanHadley circulation to orbital precession is examined in an idealized atmospheric general circulation model with an aquaplanet slab-ocean lower boundary. Contrary to expectations, the simulated monsoonal Hadley circulation is weaker when perihelion occurs at the summer solstice than when aphelion occurs at the summer solstice. The angular momentum bal...

A new numerical technique based on radial basis functions (RBFs) is presented for fitting a vector field tangent to the sphere, S2, from samples of the field at “scattered” locations on S 2. The method naturally provides a way to decompose the reconstructed field into its individual Helmholtz–Hodge components, i.e., into divergence-free and curl-free parts, which is useful in many applications ...