A pixelated complementary split‐ring resonator (PCSRR)‐loaded microstrip line is proposed for the detection of different liquid interfaces and its potential applications are described. The proposed sensor operation is based on the magnitude measurement, the transmission coefficient (S21) and resonance frequency (Fr) that depend on the electrical properties of the liquid. The PCSRR was designed to allow electromagnetic waves to interact with different layers of liquid inside a container. The sensor device and experiment system were fabricated and evaluated and water‐vegetable oil‐alcohol interfaces were measured. The sensors were capable of detecting noncontact liquid interfaces and have potential applications in the chemical, oil, and medical industries.

The efficiency of a solar tree based on golden ratio was investigated and analyzed. The lengths and angles of the trunks, main branches and sub-branches are designed using the golden ratio principle. A trunk is divided into five ranges based on the Fibonacci sequence, consisting of four main branches and four sub-branches. The angle between the trunk and main branches, main branches and the next main branches, main branches and sub-branches, subbranches and the next sub-branches is equal to 137.5° (golden angle). The solar cells are installed at the ends of all branches along the direction of each branch. The power efficiency of the proposed structure and the land-based fixed angle are compared. The measurement system consists of (a) solar cell electricity measurements (voltage and current) and (b) environment measurements (temperature, humidity, and light intensity). The data are recorded through DAQ cards (PCI 628, Elvis board and USB 6008) which are connected to the LabVIEW program for analyzes and monitors. The experimental results show that the power efficiency of the solar tree based on the golden ratio was more than the land-based fixed angle by 1.295 percent and solar cells positioned at the end of branches (T1) of the trunk can generate most power.