Nenad Teofanov

Ultradistributions and Time-Frequency Analysis

The aim of the paper is to show the connection between the theory of ultradistributions and time-frequency analysis. This is done through time-frequency representations and modulation spaces. Furthermore, some classes of pseudo-differential operators are observed.

Relating the Astronomical Timescale to the Loess–Paleosol Sequences in Vojvodina, Northern Serbia

In this study the first astronomical time scale for loess-paleosol sequences of Vojvodina region, northern Serbia is presented astronomical timescale for the loess–paleosol sequences of the Vojvodina region, northern Serbia. The sequence is the longest and most detailed orbitally tuned European loess record, comparable to Asian sequences to the east. Magnetic susceptibility (MS) records from two continuous loess–paleosol sequences in Vojvodina have been used to construct the timescale, with the aim of investigating climatic and environmental evolution and variability over the last million years. The 47.3-m-thick Mosorin (MO) section covers the time interval between marine isotope stages (MIS) 1 and 15, while the lower part of the Stari Slankamen (SS) section covers the time frame prior to MIS 16. The MS records were tuned to June 65°N insolation over the period between 0 and approximately 1 million years. The new timescale suggests older than expected ages for a number of the magnetic polarity boundaries, consistent with lock-in depth offsets reported for other loess sequences. Spectral analyses of the stacked MS variations indicate that climatic dynamics are dominated mainly by the changes in orbital eccentricity and subdominantly by obliquity and precession bands, over the past 1 million years.

Beyond Gevrey regularity

We define and study classes of smooth functions which are less regular than Gevrey functions. To that end we introduce two-parameter dependent sequences which do not satisfy Komatsu’s condition (M.2)’, which implies stability under differential operators within the spaces of ultradifferentiable functions. Our classes therefore have particular behavior under the action of differentiable operators. On a more advanced level, we study microlocal properties and prove that

MICRO-LOCAL ANALYSIS IN SOME SPACES OF ULTRADISTRIBUTIONS

\begin{aligned} {\text {WF}}_{0,\infty }(P(D)u)\subseteq {\text {WF}}_{0,\infty }(u)\subseteq {\text {WF}}_{0,\infty }(P(D)u) \cup \mathrm{Char}(P), \end{aligned}

Progressive Gelfand-Shilov Spaces and Wavelet Transforms

WF0,∞(P(D)u)⊆WF0,∞(u)⊆WF0,∞(P(D)u)∪Char(P),where u is a Schwartz distribution, P(D) is a partial differential operator with constant coefficients and

SOME APPLICATIONS OF WAVE‐FRONT SETS OF FOURIER LEBESGUE TYPES, I

{\text {WF}}_{0,\infty }