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The fuel cell stack consists of hundreds of single-chip fuel cells. The detection of each battery voltage is the basis for maintaining stable operation of the battery stack. A single fuel cell detection based on battery monitoring chip LTC6803 and PIC microcontroller is designed. The system adopts a stacked structure to realize multi-chip LTC6803 chip cascading to realize voltage detection of the series battery pack which designs hardware circuit and software program and practice proves that the system realizes high-precision detection of the fuel cell stack cell voltage.

In this paper, the differential equation of heat exchanger system is deduced according to the working principle of a vessel's heat conduction oil system. Taking the temperatures of heat conduction oil and heavy oil as the state variables, a multi-input coupled nonlinear heat exchanger model with the opening of the thyristor pressure regulating valve and heavy oil flow regulating solenoid valve as control inputs is established based on the analysis of the characteristics of the heat exchanger model. The model is decomposed into two systems: a single-input second-order linear system and a single-input nonlinear system. The sliding mode variable structure (SMVS) controller is obtained by affine nonlinear transformation of the nonlinear model. The experiments of the proportional-integral-differential (PID) and the SMVS control method based on KINGVIEW software platform are used to test the temperature of heat conduction oil and heavy oil. The results show that the SMVS control has advantages of small overshoot, fast response speed and strong anti-jamming capability.

Currently, the digital electronic speed regulator and electrical fuel injection system can only achieve independent control on engine speed and common-rail pressure, respectively. Aiming to enhance the control performance, this study proposed an idea of designing a control module to simultaneously control the diesel engine speed and common-rail pressure. Firstly, differential equations of the speed regulating system in a high-pressure common-rail diesel were derived, and a multi-input coupling nonlinear mathematical model was established by quadratic polynomial fitting, in which engine speed and common-rail pressure were used as state variables and fuel injection quantity and pulse width of fuel supply solenoid valve were used as input variables. Then, the established model was treated as an affine nonlinear system for further analysis, and a sliding-mode variable structure controller was developed. Finally, MATLAB simulation and bench test were performed to examine the control performance of the engine speed and common-rail pressure using PID and sliding-mode variable structure control algorithms respectively. Both simulation and bench test results revealed that the sliding-mode variable structure controller exhibited many advantages including small overshoot, fast response and strong resistance to interference.

In this paper, the differential equation of a cooling system is deduced according to the working principle of a vessel's central cooling water system. Taking the temperatures of low-temper ature fresh water and high-temperature seawater as state variables, a multi-input coupled nonlinear heat transfer model, with the opening of the fresh water regulating solenoid valve and the seawater regulating solenoid valve as control inputs, is studied based on the analysis of the heat transfer model's characteristics. The model is decomposed into two systems: a single-input second-order linear system and a single-input nonlinear system. A sliding model variable structure (SMVS) controller is obtained by transforming the nonlinear model into a linear reductive type. Experiments on the proportional-integral-differential (PID) and SMVS control, using the KING VIKW software platform, are carried out on the temperatures of low-temperature fresh water and high-temperature seawater. The results show that the SMVS control has certain advantages; namely, a small overshoot, fast response speed and strong anti-jamming capability.

The battle in the fight against respiratory diseases, ultrasonic atomizer more widely used, but the design of the physical characteristics complex and has always been a challenge. Based on the deep analysis of ultrasonic atomization technology, according to the choice of the atomizer plate and the best working depth and put forward the choice standard of atomizer plate. Combined with the principle of water atomization, derived optimum operating depth formula of atomizer. Then, given a variety of frequencies into the water cavitations threshold and the relationship between viscosity coefficient and frequency. At last some advices of suitable depth about circular plate atomizer are proposed.

De novo prediction of protein structures, structures prediction from amino acid sequences which are not similar to those of hitherto resolved structures, has been one of the major challenges in bioinformatics. A new prediction protein structure method based on Genetic Algorithm and Coarse-grained protein model is presented. Genetic Algorithm is a high performance optimization method and can effectively assemble a separate sequence, and Coarse-grained protein model have consistently assembled fragments are dynamically searched by Langevin molecular dynamics of conformational change. This new method combines the advantages of Genetic Algorithm and Coarse-grained protein model, which will improve the accuracy of protein structure prediction.

This paper presents a scheme to combine memory and power management for achieving better energy reduction. Our method periodically adjusts the size of physical memory and the timeout value to shut down a hard disk for reducing the average power consumption. We use Pareto distributions to model the distributions of idle time. The parameters of the distributions are adjusted at run-time for calculating the corresponding timeout value of the disk power management. The memory size is changed based on the inclusion property to predict the number of disk accesses at different memory sizes. Experimental results show more than 50% energy savings compared to a 2-competitive fixed-timeout method.