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Elliptic Curve Cryptography is a popular algorithm since it can achieve good security level with a small key size. However, the ECC hardware is suffering from some side channel attacks, such as Differential power-analysis (DPA), which can retrieve secret keys by analyzing power consumption of the attacked devices. In this paper, a countermeasure to secure the modular multiplication, an important operation of Elliptic Curve Cryptography, with randomization method is studied. The experiment results show that unprotected device reveal the secret key within 1000 power traces, while the protected one can defend DPA attack with 105 power traces, with only 8% additional area cost.

According to statistics, in the worldwide, industrial electricity consumption accounts for about 70% of the total consumption. The power consumption of the motor drive system is about 60%∼70% of the total industrial electricity consumption. When using variable frequency drive system, energy saving effect of the system is up to 20%∼40%, High efficiency design of variable frequency induction motor is conducive to improve energy-saving effect of the whole system. In this paper, a 55kW variable frequency induction motor was analyzed as an example. Based on the analysis of the composition and main influence factors of motor loss, optimize the design of the motor slot type and winding type. Propose an efficient design method of variable frequency induction motor. A prototype was made and the test results verified the design method is right.

In order to solve the problem of moving target detection caused by the ineffective calculation of the optical flow and the insufficient background compensation, an algorithm combined dynamic background compensation and optical flow is proposed. SURF (Speeded Up Robust Features) algorithm is adopted to extract the matching points and the iterative threshold segmentation algorithm is used to filter the outside point to improve matching accuracy. The motion estimation parameters are estimated by using the least-square theory. On the basis of accurate background compensation, the LK (Lucas-Kanade) optical flow algorithm is used to detect moving targets, which effectively reduces invalid background light flow calculation as well as the effect to target recognition and improves the motion target detection accuracy. Finally, VC++ and OpenCV software platform is used to design the system environment and realize the detection of moving objects in the scene of moving background. The simulation experiment results verified the feasibility of the proposed algorithm.

In the marine power propulsion system, when a synchronous generator-transformer-converter system is operating, the output electric quality is very important. Traditional analytic solution is difficult to consider the damper circuit, tooth-slot effect, winding distribution effect. Thus, the finite element method coupled circuit in time domain is employed in this paper to analysis voltage waveforms. This method has very important significance to predict generator-converter system performance accurately and configure filter device properly.

This paper presents a marine motor control strategy based on the combination of indirect vector control and feedforward compensation. Through the torque feedforward link, desired electromagnetic torque is acquired. Assisted with indirect vector control, desired quadrature-axis currents are obtained with respect to the calculated motor torque and given direct-axis current. Then the two currents are substituted into the voltage feedforward link for the purpose of deriving direct-and quadrature-axis voltages for SVPWM implementation. Matlab-based simulated results prove the correctness and validity of the proposed methodology.

The power sources with different frequencies are needed in modern shipboard power system, while conventional variable frequency generator set can't satisfy the various requirements. A novel doubly-fed speed-adjustable variable frequency generator set is studied and the stator flux oriented vector control strategy and its application under shipboard power system voltage and frequency fluctuations are analyzed in this paper. The whole model of doubly-fed speed-adjustable variable frequency generator set is built and used to simulate the speed-adjustable process. The simulation results show that the speed-adjustable performance of the variable frequency generator set is excellent and can satisfy the requirements of shipboard applications.

A design method for high-speed energy storage electric machines on basis of boundary constraints is presented in this paper. The motor power, storage energy and rotor's mechanical robustness are regarded as boundary constraints. This strategy is capable of deciding necessary dimensions of the machines, and optimizing energy density. In the meantime, rotor material mechanical robustness can be employed sufficiently, and critical speeds can stay out of the operating speed range when the electric machine charges or discharges. The rotor is integrated with the flywheel, which guarantees high integration and high energy density of the electric machine.

To improve the teaching effectiveness of fundamental chemistry curriculum system in Research University, the importance of experiment teaching should be sufficiently realized. The reform approaches that should be adopted in university are presented in terms of the interaction with theory teaching, the development of level and quality of experiment teaching, as well as the construction of software and hardware resources. Development of curriculum system, teaching model and available resource particularly contributes towards improving the interest of students and the effectiveness of fundamental chemistry courses.