A wideband dual-polarized aperture antenna array is presented based on elements formed by pairs of octagonal rings. The octagon ring elements are linked by capacitors and kept a defined distance from a ground plane. A broader frequency bandwidth has been achieved by placing a further layer of conductive elements above the array forming a meta-material layer. Expanded polystyrene foam is used to...

Prasanna Kumar G.V. (2015): Geometric performance parameters of three-point hitch linkage system of a 2WD Indian tractor. Res. Agr. Eng., 61: 47–53. Geometric performance parameters of three-point hitch system of a most sold model of a 2-wheel drive Indian tractor were determined by generating the path of upper and lower hitch points by kinematic linkage analysis. At various locations of pivot ...

Improved human-tractor interface designs, such as well-accommodated operator enclosures (i.e. cabs and protection frames) can enhance operator productivity, comfort and safety. This study investigated farm-worker anthropometry and determined the critical anthropometric measures and 3-D feature envelopes of body landmarks for the design of tractor operator enclosures. One hundred agriculture wor...

In the new agricultural scenarios, the interaction between autonomous tractors and a human operator is important when they jointly perform a task. Obtaining and exchanging accurate localization information between autonomous tractors and the human operator, working as a team, is a critical to maintaining safety, synchronization, and efficiency during the execution of a mission. An advanced loca...

Introduction Direct energy expenses (diesel, gasoline, propane, electricity) total more than $1 billion annually for Iowa’s farmers. Day-to-day farm management techniques such as adjusting tractor gear and throttle settings or monitoring tractor tire inflation pressures can reduce diesel fuel consumption for row crop production. This study is being conducted over multiple years to measure the e...

We present almost linear area bounds for drawing complete trees on the octagonal grid. For 7-ary trees we establish an upper and lower bound of Θ(n1.129) and for ternary trees the bounds of O(n1.048) and Θ(n), where the latter needs edge bends. We explore the unit edge length and area complexity of drawing unordered trees on k-grids with k ∈ {4, 6, 8} and generalize the N P-hardness results of ...

Optical-resolution photoacoustic microscopy (OR-PAM) is an emerging technique that directly images optical absorption in tissue at high spatial resolution. To date, the majority of OR-PAM systems are based on single-focused optical excitation and ultrasonic detection, limiting the wide-field imaging speed. While 1D multifocal OR-PAM (1D-MFOR-PAM) has been developed, the potential of microlens a...