Design of compact microstrip lowpass elliptic filter with wide stop band using invasive weed optimization
In this paper, the invasive weed optimization technique is used to design a compact microstrip elliptic low pass filter with very high order suppression response. This method enhances the filter stop band bandwidth more than 8.5 f3dB and achieves 47% compactness compared with the traditional elliptic filter. The measurement results of the final optimized fabricated filter are in good agreement with the simulation ones.
Optimization of Printed Yagi Antenna Using Invasive Weed Optimization (IWO)
In this letter, the Invasive Weed Optimization (IWO) method is applied to design and optimize a printed Yagi antenna. The optimization goals are set to reach an antenna with a VSWR less than 1.5 and a high-gain radiation pattern. The fitness function is calculated by FEKO, which uses the method of moments for evaluating the structures. By implementing this simple closed-loop algorithm, the best available structure has been achieved compared to the results of the previous studies. Finally, a C-band optimized version of the antenna is fabricated and tested. The experimental data are in good agreement with the simulation results, which verifies the performance of the IWO method.
LABORATORY AND FIELD TESTING OF SEED SPACING UNIFORMITY FOR SUGARBEET PLANTERS
Five planter configurations were evaluated for seed spacing uniformity at three field speeds using a seed 
location method in the field and a laboratory method involving an opto-electronic sensor system. Planter seed spacing 
uniformity was described using the Coefficient of Precision (CP3) measure. Results showed that CP3 measures 
determined using the laboratory test method were significantly different from those determined using the field test method. 
This indicated the laboratory test method cannot be used to predict planter seed spacing uniformity in the field. Seed 
spacing uniformity determined in laboratory tests was higher than, or equal to, seed spacing uniformity determined in 
field tests. This indicated the laboratory test method may be useful to screen out planters or planter units with poor 
uniformity of seed metering. Field testing of the planters that perform well in laboratory tests must be conducted to 
adequately determine the seed spacing uniformity of those planters in the field. Results from laboratory and field tests 
could be useful in determining areas for improvement of planters or planter units.