Design of Saline Gel Coil for Inner Heating of Electrolyte Solution and Liquid Foods under Induced Electric Field

As an emerging electrotechnology, induced electric field has attracted extensive attention in the development of innovative heat treatment equipment. In this study, a resistance heating unit based on induced electric field was built for inner heating of aqueous electrolyte solutions as well as liquid foods, such as vinegar. NaCl solutions and liquid foods with different conductivity were used to investigate the thermal effect and temperature rise of samples. Saline gel composed of 3% agar powder and 20% NaCl acted as a coil of conductor for inducing high-level output voltage. The utilization of the saline gel coil significantly improved the power conversion efficiency of the heating unit as well as the heating rate. The results revealed that duty cycle and applied frequency had immediate impact on the efficiency of inner heating. Additionally, the rate of temperature rise was proportional to the conductivity of the sample. The temperature of 200 mL NaCl solution (0.6%) increased from 25 °C to 100 °C in 3 min at 40% duty cycle and 60 kHz of applied frequency, and it was a circulating-flow process. The maximum temperature rise of black vinegar was 39.6 °C in 15 s at 60 kHz and 60% duty cycle, while that of white vinegar was 32.2 °C in 30 s under same conditions, whereas it was a continuous-flow process. This novel heating system has realized the inner heating of liquid samples.

Event Visualization and Trajectory Tracking of the Load Carried by Rotary Crane

Tracking the trajectory of the load carried by the rotary crane is an important problem that allows reducing the possibility of its damage by hitting an obstacle in its working area. On the basis of the trajectory, it is also possible to determine an appropriate control system that would allow for the safe transport of the load. This work concerns research on the load motion carried by a rotary crane. For this purpose, the laboratory crane model was designed in Solidworks software, and numerical simulations were made using the Motion module. The developed laboratory model is a scaled equivalent of the real Liebherr LTM 1020 object. The crane control included two movements: changing the inclination angle of the crane’s boom and rotation of the jib with the platform. On the basis of the developed model, a test stand was built, which allowed for the verification of numerical results. Event visualization and trajectory tracking were made using a dynamic vision sensor (DVS) and the Tracker program. Based on the obtained experimental results, the developed numerical model was verified. The proposed trajectory tracking method can be used to develop a control system to prevent collisions during the crane’s duty cycle.

Research on the Dual Modulation of All-Fiber Optic Current Sensor

Acousto-optic modulator (AOM) and electro-optical modulator (EOM) are applied to realize the all-fiber current sensor with a pulsed light source. The pulsed light is realized by amplitude modulation with AOM. The reflected interferometer current sensor is constructed by the mirror and phase modulation with EOM to improve the anti-interference ability. A correlation demodulation algorithm is applied for data processing. The influence of the modulation frequency and duty cycle of AOM on the optical system is determined by modeling and experiment. The duty cycle is the main factor affecting the normalized scale factor of the system. The modulation frequency mainly affects the output amplitude of the correlation demodulation and the system signal-to-noise ratio. The frequency multiplication factor links AOM and EOM, primarily affecting the ratio error. When the frequency multiplication factor is equal to the duty cycle of AOM and it is an integer multiple of 0.1, the ratio error of the system is less than 1.8% and the sensitivity and the resolution of AFOCS are 0.01063 mV/mA and 3 mA, respectively. The measurement range of AFOCS is from 11 mA to 196.62 A, which is excellent enough to meet the practical requirements for microcurrent measurement.

Wide Bandwidth Silicon Nitride Strip-Loaded Grating Coupler on Lithium Niobate Thin Film

In this research, a vertical silicon nitride strip-loaded grating coupler on lithium niobate thin film was proposed, designed, and simulated. In order to improve the coupling efficiency and bandwidth, the parameters such as the SiO2 cladding layer thickness, grating period, duty cycle, fiber position, and fiber angle were optimized and analyzed. The alignment tolerances of the grating coupler parameters were also calculated. The maximum coupling efficiency and the −3 dB bandwidth were optimized to 33.5% and 113 nm, respectively. In addition, the grating coupler exhibited a high alignment tolerance.

MPPT Control Strategy of Photovoltaic Cells Based on Duty Cycle Disturbance

Photovoltaic cell is a key part of solar power generation system, and whether its photoelectric conversion is sufficient is also called the maximum power point tracking problem, that is, photovoltaic cell MPPT. Different from the traditional MPPT control algorithm, this paper models and analyzes the output characteristics of solar cell. on this basis, proposes a fuzzy control algorithm based on duty cycle disturbance, and simulates it with MATLAB. The result shows the algorithm can well take into account the tracking speed and control accuracy when the external environment change.

Development and testing of a light dimming control using arduino uno

Increasing population and human needs have an impact on increasing the need for electrical energy. One of them is for lighting needs. Therefore, it is necessary to save the lighting system so that energy consumption is minimum and the need for lighting is optimal, by controlling light dimming. This paper presents an implementation and testing of a dimming light control using an Arduino Uno microcontroller. The circuit used a 12-volt power supply, as a voltage source, to increase to 42 volts, to meet a lamp voltage, through a dc-dc converter. After obtaining the maximum voltage, a MOSFET cut off the voltage according to the desired light or performance level. The duty cycle was directly proportional to the output voltage, using a PWM coding to get the necessary light intensity. Some testing was conducted, including the measurement point shifting to the side. The testing results show that PMW and LDR decreased as the duty cycle increased. Nevertheless, both decreasing are different, the PWM decreased linearly with a gradient of -2.55 and the LDR decreased hyperbolically. While, the illuminance, current, and power rose as the duty cycle increased. The illuminance increased, tent to be saturated, as the power increased. However, the illuminance was reduced as the PWM and LDR increased. The illuminance decreased slightly as the measurement points shifted to the side.