Introduction: The mechanism of formation of the comet nucleus, and its resulting internal structure is dependent on the initial conditions in the region of comet formation. As primitive building blocks of the solar system, an understanding of the composition, structure and formation of cometary nuclei will provide crucial knowledge on the chemical and physical conditions in the early planetary ...

High frequency / short pulse wave propagation modeling and simulation strategies will be reviewed in this presentation invited for the special session honoring Prof. Leopold B. Felsen on his 80 birthday. INTRODUCTION Narrow and broad band wave propagation either natural or man-made environments are of interest for many decades, since the success and quality of any communication depends directly...

OF DOCTORAL DISSERTATION HELSINKI UNIVERSITY OF TECHNOLOGY P.O. BOX 1000, FI-02015 TKK http://www.tkk.fi Author Sylvain Ranvier Name of the dissertation Radiowave Propagation and Antennas for High Data Rate Mobile Communications in the 60 GHz Band Manuscript submitted November 3, 2008 Manuscript revised February 4, 2009 Date of the defence April 3, 2009 Monograph Article dissertation (summary +...

The Modal Transmission-Line (MTL) method is used to analyse the shielding effectiveness of building walls, which is an important parameter for the accurate planning of microcellular mobile networks. For that, the buildings walls are modelled as multi-layer periodic structures. After a description of the extended MTL-theory, the newly developed MTLmethod is applied to reinforced-concrete and blo...

For radiowave landmobile cellular wireless communication in ‘bad urban’ environments dominated by high rises, this paper analytically derives closed-form expressions for the trivariate and bivariate joint distributions of the time-of-arrival and two-dimensional azimuth-elevation direction-of-arrival of the uplink multipaths. These expressions are explicitly in terms of the parameters of a ‘geom...

Directional modulation (DM), as an efficient secure transmission way, offers security through its directive property and is suitable for line-of-propagation (LoP) channels such as millimeter wave (mmWave) massive multiple-input multipleoutput (MIMO), satellite communication, unmanned aerial vehicle (UAV), and smart transportation. If the direction angle of the desired received is known, the des...

Conventional vibrational spectroscopies such as infrared absorption and spontaneous or coherent Raman scattering provide a one-dimensional projection of intermolecular and intramolecular vibrational structure and motions onto a single frequency (or time) axis. For simple molecules with well-separated eigenstates, this gives direct information on energy levels and their oscillator strengths. The...

A family of localized solutions of Brittingham’s type is constructed for different cylindric coordinates. We use method of incomplete separation of variables with zero separation constant and, then, the Bateman transformation, which enables us to obtain solutions in the form of relatively undistorted progressing waves containing two arbitrary functions, each of which depends on a specific phase...

due to draw-down, fears associated with declining grain yields over time, rising oil prices (which directly impact the cost of fertilizer, irrigation and transportation), hoarding (which always forces prices up), and kneejerk policy reactions from numerous governments around the globe who normally claim to be committed to free trade — what they did was suspend exports, make non-market (secret) ...

A UWB pulse radar is promising as an environment measurement method for household robots and rescue robots. SEABED algorithm, one of the radar imaging algorithms, can estimate 3-D target shapes in a short time, which cannot be accomplished by conventional algorithms. However, the estimated image of SEABED algorithm has a systematic error even in a noiseless environment, which is caused by the d...