The degrees of freedom (DoF) concept is very useful for studying the multi-user communications system at high signal-to-noise ratio region. The research on DoF leads to an important technology advancement in wireless communications, the interference alignment. The idea of interference alignment is to design the transmit signals structurally such that the interference signals from multiple inter...

We review recent results, obtained with P. Fendley, on frustration of quantum charges in lattice models for itinerant fermions with strong repulsive interactions. A judicious tuning of kinetic and interaction terms leads to models possessing supersymmetry. In such models frustration takes the form of what we call superfrustration: an extensive degeneracy of supersymmetric ground states. We pres...

ABSTRACT We present a formalism for evaluating the degrees of freedom (d.o.f.) in the communication with electromagnetic waves. We show that, although in principle there are an infinity of d.o.f., the effective number is finite. This is in agreement with the restricted classical theories. We further show that the best transmitting functions are the solutions of a specific eigenvalue equation. T...

We use calorimetry and dilatometry under hydrostatic pres7 sure, X-ray powder diffraction and available literature data in a series 8 of composition-related orientationally disordered (plastic) crystals to 9 characterize both the plastic and melting transitions and investigate 10 relationships between associated thermodynamic properties. First, gen11 eral common trends are identified: (i) The t...

Degree-of-freedom of a general mechanical system is defined as the minimum number of independent variables required to describe its configuration completely. The set of variables (dependent or independent) used to describe a system are termed as the configuration variables. For a mechanism, these can be either Cartesian coordinates of certain points on the mechanism, or the joint angles of the ...

This paper studies the sensitivity to the observations of the block/group Lasso solution to an overdetermined linear regression model. Such a regularization is known to promote sparsity patterns structured as nonoverlapping groups of coefficients. Our main contribution provides a local parameterization of the solution with respect to the observations. As a byproduct, we give an unbiased estimat...

The collective description of the octupole degrees of freedom has been a long standing problem in nuclear physics @1#. The phenomenological description of low-energy vibrational states @2,3# discussed them in terms of simple ‘‘surface modes’’ thus allowing for the description of the octupole degrees of freedom in terms of seven collective variables a3m @2,4#. In the 1980s, theoretical calculati...