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In order to estimate relationships among growth potential and biochemical indicators of Japanese flounder, RNA and DNA as well as protein indices were measured from 5 days after hatching (DAH) to 45 DAH. Results showed that the RNA/DNA ratio and protein/DNA ratio had obvious relations with instantaneous growth rate (G M ) and length-based instantaneous growth rate (G L ) during the premetamorphic period. Significant negative correlations among protein/DNA ratio and G M and G L were then observed during metamorphosis. During the postmetamorphic phase, the RNA/DNA ratio was positively correlated with G M and G L . Data indicated that body growth of Japanese flounder is mostly hyperplastic before 20 DAH, hypertrophic until 27 DAH, and hyperplastic until the end. In order to investigate the effect of diel periodicity on RNA/DNA ratio in larvae of the fed and starved groups, an experiment was conducted for 2 days. Results showed that the average RNA/DNA ratio in the daytime was higher than that in the dark and the ratio in fed larvae was higher compared with that in starved ones. In order to examine starvation effect on RNA/DNA ratio, experiments were conducted from 20 DAH to 27 DAH. Juveniles were divided into five groups: a fed group and groups starved 1, 2, 3, and 4 days followed by refeeding. Results showed that the RNA/DNA ratio increased in the fed group and declined continuously in the starved group. After refeeding, the recovery of the RNA/DNA ratio was observed for 1-day, 2-day, and 3-day starved treatments but was not found for the 4-day starved treatment.

To break through the drawbacks of the one-mass vibrating screen like plugging screen, high noise and etc., a new vibration screen with two-mass and high energy which could generate transient high vibration intensity was analyzed. To meet the requirements of energy-saving and system stability, a spring with nonlinear and hard features was used in the main vibration system. In this case, the springs stiffness could change along with the vibration intensity. The stiffness of the vibration isolation spring could be determined by analyzing the vibration isolation coefficient, and then the hollow cylindrical rubber spring with internal damping was adopted in the vibration isolation system. On the one hand, this vibration isolation spring could effectively absorb transient high vibration intensity which passed from main vibrating spring to the lower mass. On the other hand, it could achieve good effect of vibration isolation between the lower mass and the foundation. Base on field testing, the vibration intensity was increased by 28%, meanwhile, the noise was reduced by 4% and the impact vibration to foundation was reduced by 24% , which successfully solved the plugging screen problem and also verified the validity of the vibration isolation system.

To achieve the design goals of transmission with small size, light weight and low cost, the pushrod harmonic mechanism which is consist of harmonic planetary and cam mechanism is proposed, and the speed-down device of low-speed motor is changed from external installed to interior installed. Based on the mechanism principle analysis, derivation of contour equation and kinematics analysis, the centroid movement theorem of the pushrod roller and the mechanism dynamic is analyzed when the sports vice friction was considered and ignored. The total reaction force and the action line are gained. These data can provide evidence for mechanism simulation, efficiency analysis and reliability design.

The flexible smart structure is broadly applied in various fields. In order to reduce the vibration of smart structures, a dual loop PD control strategy is proposed based on the Lagrangian dynamics mathematical modeling of the flexible system and a revision of the traditional LQR algorithm, the simulation and physical experiments show that the proposed approach is efficient in controlling and damping out the vibration and disturbance in flexible smart structure system.

The vibration-stress field could be formed by high vibration intensity in vibration machine to improve the ability of the collision, shock, shear and extrusion for the system, and it also can avoid plugging screen for vibration screening machine, which could make for solving some special requirements of the vibration machine. To research the vibration machines strongly nonlinear and high vibration intensity characteristic such as certain excitation and uncertain response, the vibration machine with its double-mass is built, and its vibration exciter uses two partial blocks as vibration motor. In addition, dynamic vibration differential equation is established. To achieve high vibration intensity results based on the vibration machines safe working, the advanced control based on the SCM and Intelligent frequency conversion is put forward, and the advanced control system with its host computer, frequency converter, SCM, charge-amplifier, sensor and the vibration machine is been established.

A pushrod harmonic institution which is consisted of harmonic planetary and cam mechanism is proposed. As a result, speed-down device of low-speed motor is changed from external installed to interior installed. Design goals of the transmission with small size, light weight and low cost is achieved. Based on the mechanism principle analysis, the theoretical profile equation of the pushrod roller is deduced, then the displacement, velocity and acceleration equation of a random points are got by the analysis method. It is helpful to analyze the change of each motion parameters and the amplitude for the influence of the movement characteristics, at the same time provides evidence for mechanism simulation, kinematics parameters optimization and high-quality manufacturing of the equipment.

The effective control of high-vibration intensity frequency and its overtime and over-limited is a bottleneck technology of chaotic vibration machine to finish specific operation. A PLC advance control system based on intelligent frequency is developed. Prediction of the possible vibration intensity extreme points and its distribution are processed data mining and prediction by sensor signal amplification, analog-digital conversion, and online monitor. Moreover, advanced control of the overtime and over-limited vibration intensity is achieved by constraint conditions correction and real-time feedback. The advanced control results can be verified by comparing grinding effect of conventional vibration mill with that of advanced control vibration mill. Further, the deaggregation and refinement of super-hard and superfine grinding can be achieved.