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At present, with the gradual development of marine technology, application of marine monitoring instruments is becoming increasingly wide, for which there are more and more types of such instruments, and an increasing amount of electric energy is thus consumed. Continuous working period of such instruments and the further extension of their functions are obviously restricted by the link of electric energy supplement. Tidal current energy is a renewable energy in abundant reserve. In this paper, an electric energy supplementing device for drag-type marine monitoring instruments based on electricity generation with tidal current is designed, and its good functions are proved through water tank experiment, for which it can provide energy supplement to marine monitoring instruments.

The study on Arctic sea ice change and its influence to the global climate has become one of the most important scientific propositions. It is necessary to development the equipment with high reliability for monitoring Arctic sea ice change. In this paper, we design a low cost and long life ice buoy based on GPS and ARGOS PMT. The MCU of the system adopts low power consumption enhanced 8051 SCM (Single-Chip Microcomputer), which could collect the environmental parameters by all kinds of sensors, such as atmospheric pressure, temperature (air and sea ice), humidity, position of sea ice, and so on. Through optimizing circuit design and adopting intelligent power management method, the system could operate under very low power consumption. Meanwhile, we adopt the supercapacitor to supply the required large electric current of data transmission. By above methods, it efficiently prolongs the batteries life so as to ensure the long life of the ice buoy. Several prototypes of the ice buoy were deployed on the Arctic sea ice one and a half years ago, and some of them have still operated normally until now. The buoys operating status and the data validity indicate that it is an effective means to observe Arctic sea ice environment by deploying this kind of ice buoy.

Tidal current energy of sea surface is a kind of renewable energy with wide prospect of development. Because of its relatively high utilization ratio, the horizontal-axis turbine generation system utilizing tidal current energy has become the focus of technology development of tidal current energy all over the world. In this paper, the authors analyze the characteristics of surface tidal current energy along the coast of China. Meanwhile, we use BEM mathematical model to design the 2.5kW Horizontal Axis Tidal Current Energy Turbine Generator Blade, which is suitable for the features of tidal current energy in our country. The result of the prototypes dragging experiment indicates that this design method has good application value.

The research of Metamorphosis hydraulic model experiment which is designed on the base of gravity similarity and turbulent resistance similarity into SUE Hydropower Station shows the structure layout and design size of SUE Hydropower Station are reasonable and overflow capacity of sluice can meet the requirements. Upstream circular-arc concrete guide wing wall and the guide wall between downstream stilling basin and power station outlet can play a role of diversion and smoothing the flow pattern. When the flow is more than design flow, the effect of energy dissipation and erosion control of stilling basin is not good. In order to enhance the effect of energy dissipation and erosion control of stilling basin, the basin shall be lengthened and baffle piers shall be set in the stilling basin to assist energy dissipation.

The structure, carrier concentration and low temperature magnetoresistance of Tantalum-doped Tin oxide thin films prepared by RF magnetron sputtering method have been investigated. Hall coefficient is negative at all measuring temperatures, which confirms the n-type characteristic of the films with metallic characteristic. The low temperature magnetoresistance measurement show negative magnetoresistance at all measured temperatures from 2 to 30 K. However, weak-localization theories can not explain the behavior of the negative magnetoresistance of our samples. We fitted the magnetoresistance data of the samples with semiempirical expression that takes into account the third order sd exchange Hamiltonians. The theory and experiment are in excellent agreement. This strongly suggests that the magnetoresistance in SnO2: Ta film originates from the scattering of conduction electrons due to localized magnetic moments.

Though there are a lot of rules and models for metal material fracture, it makes lots of troubles for engineering application, because of the lacking of reasonable description of fracture principle and change law. This article discusses some basic problems of applying fractal geometry to fracture research, mainly including sectional fractal characteristics and measurement, the relationship of fractal dimension and fracture toughness, and some kinds of metal fractal models. At last, application of fractal theory in metal fracture is stated.

Based on the rolling of explosive welded composite sheet the paper described the feature of press working of the explosive welded composite material metals as well as their technologies, structures, properties and applications ,pointing out that combination of explosive welding with the traditional press working process is a new route of significant importance to manufacturing composite material metals with different varieties, shapes, dimensions, properties and applications and thus can achieve greater economical, technical and social benefits.

Step voltage of lightning can make serious human casualties. According to some doubt about the step voltage protective measures in IEC 62305-3 (2010), we get the calculation formula of step voltage through derivation, and verify the high soil resistivity around building foundation surface is likely to endanger human life. With the research of Lightning Real-time online Monitoring Project, calculate and examine the range of dangerous step voltage, which is helpful to the work of risk assessment and disaster survey.

The effects are unsatisfactory to adopt plain control mode for air-con refrigerating system with large lagging and nonlinearit features. The mechanical properties of electronic expansion valve are not sensible. In this article, BP-PID controller is adopted to control the system’s electronic expansion valve opening mechanical properties. The controller is designed. The experiment results show the controller is simple and effective, and well fulfills the users’ actual needs.

In order to precisely control the injection responsivity of the Gasoline Direct Injection（GDI）engine，a higher requirement of the injector drive circuit should be achieved[5]. This paper introduces a new design of driving circuit for the injector of the EA888 engine. the thesis creates a simulation model of BOOST converter circuit using multisim simulation tool, Simulation results show that voltage ripple is less than 10%.The characteristics of GDI injector are measured and analyzed , the feasibility of the driving circuit is verified.

The Ti1.4V0.6Ni ribbon alloy containing icosahedral quasicrystal is prepared by melt-spinning technique, and the Ti40.33Zr40.33Ni18.34 icosahedral quasicrystal powders are prepared by mechanical alloying. Both samples are annealing in a vacuum furnace. DSC trace obtained during continuous heating to 1300°C show a distinctly broad exothermic peak between 100°C and 1000°C for the Ti1.4V0.6Ni alloy, two sharp exothermic peaks between 100°C and 700°C for the Ti40.33Zr40.33Ni18.34, respectively. The magnetic behavior results demonstrated the Ti1.4V0.6Ni ribbon alloy exhibited higher ferromagnetic properties than those of Ti40.33Zr40.33Ni18.34 powders both at 15 K and 300 K. The specific heat capacity of two the sample increase when the temperature increase from 400 to 650°C.

Ba0.9Sr0.1TiO3 ferroelectric ceramics with dopants of La2O3(0, 0.1, 0.1, 0.2 mol%) and Nb2O5(0, 0, 0.1, 0.1 mol%) were prepared in solid state process. The double donor substitutions can weaken lattice size effect by the two different size substitutions. XRD method was used to analyze the crystal structure of the samples, and SEM was used to observe the topography, grain’s size and ceramics density. The results of dielectric-frequency relation indicate that when the contents of La2O3and Nb2O5are both 0.10 mol%, the permittivity can reach to 150 000, and the dielectric loss keeps only 0.118. When the total donor content is lower than 0.40 mol%, compensation effect is dominated by electrons. The giant permittivity is attributed to electrons inside grain and insulated grain boundary. When the dopant content is higher than 0.40 mol%, the compensation effect is dominated by the host cation vacancies. The permittivity decreases rapidly with the increase of the donor concentration.

This paper has set up the electro-hydraulic servo mathematical model for loader working device and devises a device motion controller with H∞ mixed sensitivity algorithm in order to improve loader’s automaticity and maneuvering performance. This paper has done some simulation research of the servo motion controller with Matlab/Simulink. And research has shown that the H∞ robust controller may improve working device’s automaticity and maneuvering performance enormously, the device motion controller has well robust stability and performance.

Laser tailor-welded blanks is one of the widely used in automotive industries as it reduces manufacturing cost and weight and also improves the quality of the components. The effects of difference in material properties, welding properties on blank formability become important in various forming processes. In this study the welding property of different gauge laser tailor-welded blanks was observed in microhardness and microstructure aspect. The property effects on the formality of the tailor-welded blanks were discussed. That the laser welded joint is qualified to satisfy the demand of sheet forming.

The discovery of the icosahedral quasicrystalline phase (i-phase) in as-cast Ti40.83Zr40.83-xScxNi18.34(x = 0~2.0) alloys is described herein. The effect of Sc on the structure and mechanical properties of the bulk quasicrystalline alloys is investigated. The results show that the phase structure of the as-cast alloys are mainly composed of icosahedral phase accompanied by minor C14 Laves phase (L-phase), and the mechanical properties of the bulk quasicrystalline alloys have been examined at room temperature, the compressive fracture strength first increased and then decreased with increasing x from 0.4 to 2.0, and the highest strength is near 1400 MPa when x =1.2, it was 380 MPa higher than the without Sc alloy. The bulk quasicrystalline alloy exhibits the elastic deformation by the compressive test, and the fracture mode was brittle cleavage fracture.

The paper introduces some effective methods to solve the problems of solid modeling with the software of AutoCAD. Make good use of views to avoid converting UCS frequently and set up proper layers aimed to the building or structure and draw solid in order to control the display of different parts of solid. According to analysis and research on 3D solid model, the authors also point out other techniques, such as the skills about Boolean Calculation and conclude that different operation sequence produces different result and sometimes don't need to input a data and also complete to cut of solid. These skills are helpful to make solid model.