Field evaluation of a vibrating dual bent-share cultivator

Field evaluation of a dual bentleg plow

Performance Evaluation of Draught Animal Power Cultivator

Prefix 10.18034 This performance evaluation was conducted to pave the way for making use of Draught Animal Power Cultivator and cosequently possibilities of adaptation in our local condition between 2010 and 2011 in the Jimma zone two districts of southwestern Ethiopia on the farmers’ field to evaluate energy requirement. To improve weed management at the small holder farmers level, animal-draw...

Self-dual bent functions

A bent function is called self-dual if it is equal to its dual. It is called anti-self-dual if it is equal to the complement of its dual. A spectral characterization in terms of the Rayleigh quotient of the Sylvester Hadamard matrix is derived. Bounds on the Rayleigh quotient are given for Boolean functions in an odd number of variables. An efficient search algorithm based on the spectrum of th...

On the dual of (non)-weakly regular bent functions and self-dual bent functions

For weakly regular bent functions in odd characteristic the dual function is also bent. We analyse a recently introduced construction of nonweakly regular bent functions and show conditions under which their dual is bent as well. This leads to the definition of the class of dual-bent functions containing the class of weakly regular bent functions as a proper subclass. We analyse self-duality fo...

Near-Field Acoustic Holography of a Vibrating Drum Head

This paper explains the design and construction of a phase-sensitive near-field acoustic holography apparatus. By using phase-sensitive lock-in amplifier techniques to record the complex signals of pressure and particle velocity microphones over an extended spatial region, small vibrations can be imaged using the acoustical properties of said vibrations. The apparatus is tested on a vibrating d...