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The access problem of new energy is one of the core content of the smart grid. New energy such as wind, solar, electric vehicle charging stations have strong intermittent and fluctuations. Their technical performance is poor to access to the grid.They inject harmonics into grid and have other issues. This paper describes the impact on the distribution network after the wind, photovoltaic power generation, electric vehicle charging stations connected to the grid.It is hoped that you can build smart grid distribution model,research in-depth and analysis the combined effects of smart distribution grid after new energy sources accessed, to achieve the monitoring of the various components of the distribution network and the best combination for electricity.

To study the effects of Cu/Ba ratio of precursor on YBa2Cu3O7-x (YBCO) film, we have employed the technique of metal-organic chemical vapor deposition to prepare 500 nm thick YBCO films on CeO2/YSZ/Y2O3 (YYC) buffered Ni-W alloy tapes at series of Cu/Ba ratios of precursor. The analysis obtained from X-ray diffraction and scanning electron microscope revealed that the YBCO films crystallized better and became more continuous and denser as Cu/Ba ratio increased from 0.81 to 1.00, yielding that the critical current density (Jc) of YBCO films at 77K and 0T rose from 1.0 MA/cm2 to 1.4 MA/cm2. Moreover, the energy dispersive spectroscopy indicated that the increase in Cu/Ba ratio of precursor made the Cu/Ba ratio of the YBCO film matrix closer to the theoretical value of 1.5. However, for the Cu/Ba ratio of precursor in the range of 1.00~1.21, the crystallization and texture deteriorated severely and many unexpected precipitates of Ba-Cu-O and Cu-O arose, resulting in the dramatic drop of Jc from 1.4 MA/cm2 to 0.1 MA/cm2.

With the development of society and science,Our country began to advocate "green environmental protection, energy conservation and emissions reduction". Construction as an important component of the national economy, have begun to attach importance to the development of electrical energy-saving technologies. Energy-saving technology can save resources, ease the energy crisis and to improve the quality of people's lives and the environment. In construction, the use of electrical energy-saving technology, can effectively improve the quality of construction, architectural resources, reduce waste, improve resource utilization. This paper briefly describes the electrical energy-saving technologies, analyzing the status of construction, energy-saving technology in the construction of electrical engineering.

Carboxymethyl chitosan aerogel was prepared by freeze-drying method with glutaraldehyde as crosslinking agent. The effect of different concentrations of crosslinking agent and solvent on the gel time and porosity was investigated. The absorption capacity of aerogel was investigated with different oils (gasoline, diesel oil, peanut oil, dimethyl silicone). The results were shown as 1) the highest porosity of the aerogel was 95.01% and the lowest density was 0.026g/cm3. 2) The optimum preparation condition was the concentration of crosslinking agent 20%, the solvent concentration 2%. Oil absorption capacity of the aerogel was up to the maximum of 28.6g/g (to dimethyl silicone), which was higher than to the other three oils. This work offered a preparation method for the high porosity, high oil-absorbing massive carboxymethyl chitosan aerogel and revealed its potential application in the treatment of oil pollution.

Reinforcement corrosion is one of the main causes for the deterioration of reinforcement concrete structure. And it seriously affected mechanical properties of anchor structure system of underground engineering under complicated erosion environment. Based on elastic theory and assumption of maximum tensile-stress failure criterion, together with construction process of anchor structure and rust expansion critical process, reinforcement rust expansion mechanical model of anchor structure system was simplified. Elastic criterion of different initial cracking mode was rewarded under different stress ratios. According to analysis of critical cracking mode of different medium, cracking order of mortar and surrounding rock depended on their material parameters, in-situ stress and thickness of mortar cover. Critical cracking conditions of different medium without effect of in-situ stress was rewarded. The result provides a useful reference for analysis of mechanical deterioration mechanism of anchor structure and design of support structure of underground engineering.

There have potential main-landslide and a undisturbed thin layer of siliceous rock under the left of Karst slope (K133+180), so it is easy to occur creeping slip surface because of gravity while excavating. Proceeding with geomechanics model and according to influence of heavy rainfall, two schemes proposed are analyzed by means of numerical simulation. Both the reinforcement with lattice beam and anchor cable and the reinforcement with anti-slide pile and cable satisfy stability of slope. But the second scheme has higher safety storage coefficient. And the result that the second scheme not only strength anti-shear ability but also change magnitude and trend of shear damage of potential landslide in slope is rewarded. So the restrain effect of the second scheme is better that of the first. According to engineering cost of two schemes, the cost of the reinforcement with anti-slide pile and cable is less than that of the reinforcement with lattice beam and anchor cable. So Karst slope (K133+180) is reinforced with the second scheme and it is stability undergoing strong rainfall. Experience of Karst slope (K133+180) can give useful guidance for similar projects in Karst terrain.

Recently, the fiber reinforced composite embedded with visco-elastic layer has received great attention because of its good damping capability. Damping is an important feature for dynamic behaviour of composite structures, which alleviates the resonant vibrations and thus prolongs the service life of structures under fatigue loading or impact. The present paper deals with the dynamic response of a 3D composite structure embedded with visco-elastic layer. The modal analysis, harmonic analysis and transient analysis are carried out respectively. The amplitude of z-displacement of a specific node on the bottom reduces quickly due to the high damping of the visco-elastic layer.

In this paper fiber reinforced laminated composite for engine mount model are investigated by finite element method. Static analysis is carried out to find out the maximum displacement point or node on the bottom plate, on which the displacement is optimized. Different ply orientation and combinations of 0°/45°, 0°/90° and 0°/45°/90° are then studied under sinusoidal and dynamic load conditions to examine the effect of ply orientation on the structure’s displacement transportation, and to get the optimized ply orientation combination, which inherit least displacement from the excitation on the top plate. The result shows that the laminate with ply orientation of 0°/90° is the best as the Z-displacement on the bottom is considered.

The stability of cutting system is an important research in high-speed machining area. It is widely used in engineering practice. First, this paper studies the milling forces and their change law when milling aluminum alloy through orthogonal experiment. And it solves the milling coefficients. Second, it modal parameters of milling system such as natural frequency, modal mass and equivalent stiffness by hammer experiment. On this basis, it draws the stability lobe about the spindle speed and radial depth of cut and verifies the accuracy of the stability lobe.

As technology development, projected digital fringe pattern is widely used in measuring three- dimensional (3D) shape, even in the presence of surface discontinuities. This paper investigates the reliability and accuracy of two multi-frequency phase unwrapping algorithms by experimental means. The first, which unwraps through a sequence of phase maps produced with exponentially change in spatial frequency with time, is found to be less robust and accuracy than the second, which only use three different frequency to beat new frequency for unwrapping the phase. Through experiment, the best frequency, adjacent ratio for the first method and frequency difference for the second method are proposed for the high efficiency and accuracy measurement.

V2O3 and VN nanocrystals have been conveniently synthesized from thermal ammonolysis of the precursor VOC2O4•H2O in a resistance tubular furnace at 500°С and 780°С for 30 min, respectively. The products were characterized by X-ray diffractometer (XRD)、X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) techniques. The average particle sizes of V2O3 and VN are both in the ranges of 20~35 nm. The evolution from precursor to hexagonal V2O3 and then to cubic VN was explored. The crucial factors，such as the reaction temperature and time，have also been discussed.

Based on isolation theory, time-history analysis on isolation system with limiting displacement protective devices was studied by Fortran program. Isolation effect of non-isolated structure, isolated structure and limit isolated structure were analyzed. Adhesion phenomenon of algorithm is solved by subdividing time steps during program analysis. And it gets good effect. According to comparing with isolation effect of different isolated structure, the result that isolation effect of isolated structure and limit isolated structure is obvious is reward; and limit isolated structure can isolation and prevent large displacement of isolation layers to avoid structure failure under rare earthquake condition. So limit isolated structure plays a double protection for structure.

In this paper, a 3D shape measurement system based on a digital fringe projection and phase-shifting technique was described. The fringe generated by a computer was projected onto the object by utilizing a digital video projector. Four steps phase shifting algorithm was used to calculate the 2π wrapping phase, and a heterodyne principle was used to unwrap the phase to obtain the real phase. Then the 3D coordinates object was calculated base on stereo vision algorithm by using the real phase as a constraint. Experiments demonstrated that the system was not sensitive to the phase error caused by the DVP’s nonlinearity.

The material recognition and size measuring cell is very important for the development and practicability of flexible manufacturing system (FMS). However, the existing FMS mostly recognize the two-dimensional shape of the workpiece, measure the one- dimensional shape of the finishing product. This greatly limits the performance of FMS. In this paper, these cells have been optimally designed to identify and measure the three-dimensional shape of the workpiece based on the optical measurement principle. The method has the advantage at robust recognition rate and high recognition quality.

This paper presents a stable least squares ellipses fitting algorithm based on Zernike orthogonal moments. The algorithm uses Zernike orthogonal moments for sub-pixel edge detection, and a mask of seven multiply seven was derived in the meantime. The optimal ellipse parameters were computed according to the data points extracted previously. This stable, robust and non-iterative algorithm can be easily implemented. The experiment results show that the proposed algorithm is effective in various situations.