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Active distribution network with energy storage system is an important outlet for a mass of distributed renewable energy connected to the grid. In this context, a hybrid energy storage system is proposed based on NaS battery and lithium ion battery, that the former is the main large scale energy storage technology world-widely used and developed and the latter is a flexible way to have both power and energy capacities. The hybrid energy storage system, which takes advantage of the two complementary technologies to provide large power and energy capacities, is chosen to do an evaluation of economical-environmental based on critical excess electricity production (CEEP), CO2 emission, annual total costs calculated on the specific given condition using Energy PLAN software. The result shows that hybrid storage system has strengths in environmental benefits and also can absorb more discarded wind power than single storage system and is a potential way to push forward the application of wind power and even other types of renewable energy resources.

The active distribution network is an effective approach to solve the problem such as the high penetration of intermittent renewable energy. This paper constructs single and hybrid energy storage battery systems in the active distribution network, calculates the economic benefits of the single and hybrid energy storage systems from six aspects in annual electricity sale revenue, ancillary revenue, investment cost, maintenance cost, landed cost and power shortage punishment cost. Take the lithium iron phosphate battery as single system, the lithium iron phosphate battery and Lithium titanate battery as the hybrid system to compute the cost benefit. The results show that the storage systems have effects to the intermittent renewable energy in peak shaving. Since the hybrid energy storage system can obtain more annual ancillary revenue, and the batteries’ work life is longer, it has more advantage in economic benefits than the single energy storage system.

The calibration process of a digital Multi-meter (DMM) is complicated and tedious. The whole procedure needs to calibrate dozens of test points of several measuring ranges. Usually, the automatic calibration system is used to replace the manual operation. In metrology, the MAT/CAL which is a software produced by Fluke company has been widely used, but it can’t meet our special needs. This article is mainly on the introduction of design method of an automatic calibration system for DMM basing on Fluke MAT/CAL. It describes the setup of hardware, the improvement of ACC file in MAT/CAL and the basic principle of our software.

Ionizing radiation total measurement response of Schottky Diode were studied, Investigation result shows radiation causes decrement of breakdown reverse voltage and increment of leakage currents. More steps theoretical analysis shows radiation induced new interface state which causes performance degeneration of device, thus changes density distribution of interface state and modules Barrier Height of Schottky Diode.

In this paper, we studied a smart base isolation system based on magnetorheological elastomers (MRE), which is a new class of smart materials whose elastic modulus or stiffness can be adjusted by changing the magnitude of the applied magnetic field. The main goals of this study are to demonstrate the use of MREs as field-dependent element in a smart base isolation system and investigate the dynamic performance of the smart base isolation system in mitigating excessive vibrations of the building structure under dynamic loadings. To this end, we designed some MRE samples working in compressive mode and measured their properties under various magnetic fields in which the elastic modulus varied by up to 250%.Compared with the structure installing traditional base isolation system, the dynamic performance of the structure installing smart base isolation system is much better under the dynamic loadings.

For the finger seal, leakage and wear are key factors to affect its sealing performance and service life. To reduce the wear of the finger seal, C/C composites are probably used for finger seal material preparation for its self-lubrication and light weight properties compared with the metal. The work to be presented here assessed the elastic properties of the 2.5D C/C composites by the volume average method and established a finite element model for finger seal dynamic analysis. The results show that increasing warp yarn density and using shallow direct-joint structure can notably improve sealing performance of the finger seal, but can also increase contact pressure between the finger seal and the rotor.

Most of the studies about tilting pad journal bearings are for load-on-pad or load-between-pad tilting pad journal bearings, and for the other loading forms, the performance are often estimated by the performance of the two limited conditions, that may reduce the reliablity of bearing design or lead to waste materials in design. To obtained the influence of the load directions on the static and dynamic characteristics of the tilting pad journal bearing, which is called eccentric load effect in this papers, the performance calculation of the tilting pad journal bearing in different load directions is operated with a self-designed program. The results show that the load directions have considerable effects both on the static and dynamic characteristics of the tilting pad journal bearing, for the operating condition that load direction changed rapidly, it need performance analysis of the bearing in its special loading forms to enhance the precision and efficiency of bearing design, espacially where the dynamic performance of the tilting pad journal bearing is demanding.

Because many accidents in China involve a ship in a barge fleet colliding with a bridge pier, determining the impact force of the ship is important. To obtain an equation that describes the impact force of a ship colliding with a bridge pier, a mechanical model of the collision is simplified, and the results from other researchers are applied. Based on the equation, it is found that the impact force of a ship colliding with a bridge pier is not only relevant to the mass，velocity, board thicknesses of the ship, and the impact angle, but also to the remaining velocity coefficient. It has been demonstrated that the result from the proposed equation in this paper is in accordance with that of Gkss’s test in Wosin G theory.

With the sustainable economic development, a new multi-layer frame-bent industrial building is developed in the southeastern of China, based on a traditional bent industrial building. In this kind of structure, a framework is used in the longitudinal direction, the precast prestressed double-T plates is used in the middle layer, and the precast prestressed saddle plates is used on the roof. At present,the research achievements for this new multi-layer frame-bent industrial building under the action of earthquake .are seldom at home and abroad. In order to analyze the damaged mechanism and destroyed process on the structure of a new multi-layer frame-bent under the action of earthquake, elastic-plastic analysis of the structure must be completed. In this paper, the seismic performance of this new multi-layer frame-bent industrial building is studied by pushover analysis. The result shows that in the zone of a seismic fortification intensity as 70, both the elastic story drift under the action of frequently occurred earthquake and the elastic-plastic story drift under the action of rarely occurred earthquake for this new multi-layer frame-bent industrial building meet the requirements for the regulations of PROC;the plastic hinges appear first in the second floor, then develop to the first floor until the structure is destroyed.

At present, although the saddle plate is widely used in roof structures of single-storey industrial buildings, the seismic analysis on single-storey industrial buildings with roof of saddle plate in different span is rare. In this paper, we study the structure’s response to the frequent earthquakes and rare earthquakes by ANSYS software. We also discuss the influence on vibration characteristics and the seismic response caused by the change of saddle plate’s span. We draw the conclusion that with the increase of the span, the natural vibration period of the structure, the displacement on the top of columns and the shear force at the bottom of columns increase; but the increase rate decreases with the increase of the span. The conclusions will give a reference to the seismic design of single-storey industrial buildings with saddle plates.

A fundamental study has been performed to analysis the fluid dynamic characteristics of the gas medium in a rotating disk cavity through the commercial software CFX11.0. This paper aims to discuss the impact of the speed of rotating disk, axial and radial size and parietal lubricant film velocity and other factors on the gas flow state in cavity. Several conclusions have been obtained: the speed of rotating disk has a great impact on velocity distribution of gas flow field; the dimensionless tangential velocity of the gas medium decreases along the radial direction, and with the speed increasing, it shows a certain regularity; Dimensionless radial velocity decreases along the radial direction, and the speed of rotating disk nearly has no influence on this; The shear stress distribution along the radial direction and the distribution of tangential velocity have similar regularity; the impact of disk cavity height on the distribution of the tangential velocity along radial direction in the gas flow field is much more obvious than the impact of disk cavity width.

Along with rapid development of high-speed railway in many countries, recently research on seismic response of high-speed railway bridge under train load has raised much concern among researchers. The whole bridge finite element model is establish to analysis the seismic responses of simply-supported girder railway bridge subjected to high-speed train in this paper, ICE series high speed vehicle is employed as train live load, the vehicle is simulated by moving spring-mass system, The track irregularities can be obtained by Simpack software, the birdge incluing superstructure and substructure is three-dimensional space beam element, the bottom of piers is proposed consolidated. elastic seismic responses of bridge system and elastic-plastic deformation of piers considering different train speeds are calculated. The calculation results indicate that, seismic responses of bridge system are increase with the increase of train speed and earthquake intensity, and the bottom of piers will step into elastic-plasticity stage under high-level earthquake, the plastic hinges occurred within 1.4 meters of bottom of pier. The numerical results can provide some references for design of high-speed railway bridge.