In the present paper we establish the Wiener test for boundary regularity of the solutions to the polyharmonic operator. We introduce a new notion of polyharmonic capacity and demonstrate necessary and sufficient conditions on the capacity of the domain responsible for the regularity of a polyharmonic function near a boundary point. In the case of the Laplacian the test for regularity of a boun...

It has recently been demonstrated that zero correlation of a random multiple-input multiple-output channel is not a guarantee of its high capacity. Degenerate channels exist, which have zero correlation and still low capacity. In this letter, we provide a statistical analysis of this phenomenon, formulate the general condition for a channel to be degenerate, and propose a method to estimate its...

We apply graph theory to nd upper and lower bounds on the channel capacity of a serial, binary, rewritable medium in which consecutive locations may not store 1's, and consecutive locations may not be altered during a single rewriting pass. If the true capacity is close to the upper bound, then a trivial code is nearly optimal.

This article proposes a means by which benefits provided in international research collaborations might be employed to strengthen health care, research, and other capacities in less-developed countries. The Declaration of Helsinki and CIOMS Guidelines define certain expectations of benefits, but these requirements are ambiguous, logistically problematic, and studies suggest they are inconsisten...

This paper deals with the problem of computing channel capacity for wireless communications systems with multiantennas. The system is modelled using a transmit volume, a receive volume and a set of reflective scatterers. Based on the authors’ previous work on channel modelling of such a system, we give a multi-input-multi-output model for communications between arbitrary antenna arrays in two v...

We consider a cellular satellite system conceived to enhance the capabilities of the pan-European terrestrial system (GSM). This adopts EHF band and highly-inclined orbits. We present a preliminary assessment of system capacity based on asynchronous direct-sequence spreadspectrum multiple access (DS-SSMA). Performance is measured in terms of error probability achieved by If users simultaneously...

Introduction: A growing number of Muslim athletes now engage in international competition. This raises the question of the advice they should be given if a major event occurs during the month of Ramadan. Methods: A narrative review has been based upon books and extensive reviews completed by the author and other investigators. Results: Practical considerations hamper assessment of the effects o...

soil productivity is generally associated with poor nutrient status and the physical condition of the soil, but the effect of soil mineralogy on soil productivity has received little attention. in this qualitative study, interactions between mineralogy and physico-chemistry and their role on the productivity of two luvisols, an arenosol and a vertisol are investigated. minerals identified in th...