Conjugated bi-layer C8 metamaterials are proposed. Chirality and refractive index can be controlled effectively by the structure geometry. Extreme chirality results in a high negative refractive index for both right- and left-circular polarized excitations. The conjugated bi-layer C8 structures are fabricated and tested in microwave regimes. The measurement results are in good agreement with the simulation results. These proposed structures are additional promising candidates for high negative refractive index metamaterials which will facilitate different applications.

A detection system for water adulteration in honey is proposed. It consists of a modified SMA-connector sensor and a vector network analyzer. A modified SMA-connector sensor is applied to measure complex relative permittivity, electrical conductivity, and phase constant of honey samples with the open-ended method. The system is tested in the frequency range of 0.5–4.0 GHz at the sample temperature of 25 °C. The relationships between the complex relative permittivity, electrical conductivity, the phase constant, and the honey samples with different concentrations (0–30%w/w) are determined. The experimental results show that the real part of the complex relative permittivity is significantly proportional in honey samples with adulteration of water in the range of 0–30%w/w. The frequency of 0.6 GHz is a suitable frequency for detection with a real part of complex relative permittivity as an indicator. The frequency of 3.74 GHz is an appropriate frequency for detection with electrical conductivity as in indicator while the frequency of 4.0 GHz is suitable for detection with phase constant as an indicator. In addition, the data are analyzed with regression analysis. This technique is also performed on natural latex samples to determine the dry rubber content. The frequency of 0.5 GHz is a suitable frequency with a real part of complex relative permittivity as an indicator while the frequency of 4.0 GHz is a suitable frequency with an imaginary part of complex relative permittivity, electrical conductivity, and phase constant as the indicators. The results demonstrate that it is possible to apply this technique to determine the dry rubber content in the natural latex samples as well.

Metamaterials with near-zero refractive index designed using fishnet structures are proposed. The near-zero-index band is generated with the overlap of electric and magnetic resonances, where the transition from a negative-n region to a positive-n region is found. Both the permittivity and the permeability are controlled via geometrical parameters and the structure orientation, and are near-zero within the operating band, resulting in low loss transmission. As the number of layers increases, the transmission band becomes broader and moves to lower frequency. The experimental results confirm that such designs can generate a near-zero refractive index with low loss within an operating frequency band.

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Recently, there has been a growing interest in the field of using 3D-printing technology for electrical machine manufacturing. However, almost research works have been done majorly on the 3D-printing technology of individual working parts for various electrical machines. This research presents a study of design, fabrication and testing of the protopype of permanent magnet generator using 3D-printing technology. The major parts of proposed generator are fabricated though 3D-printed materials. The stator winding of designed generator consists of 12 slots. The stator coil is designed to have 250 turns per slot and 12 pieces of neodymium magnets are used in to generate magnetic field in the rotor core. The prototype generator is tested under different condition; no-load and loaded-test. The experimental have been shown that in the no-load condition, this generator is able to generate output voltage of 3.3-64.5 V, when rotated at speed of 100-2,500 rpm. In the loaded-test, the output voltage and output current are also generated. Furthermore, it can be seen that a proposed generator can generate the output power of 4,245.28 mW, when rotated at speed of 2,500 rpm.