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To study influence of LED light source lifetime on electricity consumption, optimization of BP neural network is adopted to establish analysis model of energy consumption for neural network, regarding environmental illumination, LED working face illumination, attenuation rates of LED lifetime as input parameters and PWM as output parameters. Under future lifetime of LED, energy consumption is predicted through the model. Results show BP neural network based on genetic algorithm can calculate energy consumption of LED light source quickly and accuracy of prediction is high. The method can be well used to predict energy consumption of short-time LED.

An advanced LED multi-die-bonding integration using a fluidic self-assembly technique is proposed in the field of flip chip packages. Different form the conventional pick-and-place methods for a single LED die bonding, the fluidic approach is a relatively new design and a batch process, which can achieve not only die self-alignment but die self-assembly. Here, the size of LED die is 1-mm-square chip with the thickness of 0.3 mm. Due to the smaller size of LED die, the die-bonding process is still in need of finding a suitable approach and breakthrough. In this study, our design of fluidic self-assembly device is based on the experimental test and simulation results. The device design is the gas-flow channels with the magnetism. The width, height and length of each gas-flow channel are 1.1 mm, 0.5 mm, and 1 cm, respectively. With the restriction of the channel width, this structure design can control well to die self-alignment. In addition, the design of two circular structures in the channel can form a flat rim to achieve the die self-assemble. This mechanism of fluidic approach can be useful to the LED die self-alignment and self-assembly in the future batch processing.

Took two layers of single span lateral sway semi-rigid connecting steel frame to bear vertical load function as the research object, adopting finite element method for solving the bucking load of the whole losing the stability of the semi-rigid connecting steel frame. Using based on the energy method and the three parabolic interpolation deflection curve function to obtain the relationship between the both element ends of internal force and displacement and introducing semi-rigid beam element stiffness matrix and geometric stiffness matrix of element integrate the global stiffness matrix which contains the flexibility of the connections and the component geometry nonlinear, thus deducing the stability characteristic equation of semi-rigid steel frame. And the MATLAB language composition program is applied to calculate the buckling load of overall losing stability of the semi-rigid steel frame, thus obtaining the buckling load of semi-rigid steel frame. The method is a very effective numerical calculating method which can solve the stability problems of relatively complicated stress conditions or relatively complicated structure composition conditions and it can also satisfy the requirement of higher calculation accuracy, easy for programming and calculation and of great practicability.

It’s important to improve the speed of security analysis of 96 period generation scheduling cases. Based on the characteristics of 96 period cases’ security analysis, four technical proposals were presented. They were following as fast scanning and analysis technology based on DC power flow screening, multiple thread parallel computing adapted to a multiple contingency case, multiple process parallel computing technology adapted to multiple period cases. Detailed test examples showed that the proposed methods could contribute much to fast security analysis of 96 period cases’ day-ahead dispatching schedule.

In order to more effectively solve some difficult problems in gearbox failure diagnosis, a gearbox fault diagnosis method based on Relevance Vector Machine (RVM) is proposed. RVM is developed in Bayesian framework. It does not need to estimate the regularization parameter with less relevance vectors, and its kernel function does not need to satisfy Mercer condition. Simulation results show that: compared with the traditional BP neural network, RVM has the faster modeling speed, more accurate diagnosis, and is worthy of promotion and application in fault diagnosis of the gearbox.

The low carbon high manganese steel (C: 0.07, Mn: 2.0, mass percentage) was deoxidized by Ti and Mg alloys, and its features of inclusion and microstructure were systemically studied. Through the scanning electron microscope (SEM) and Energy Dispersive X-ray Detector (EDX), it can be seen that in inclusions, the element of magnesium always coexists with titanium, and no single-phase oxides of magnesium are observed. After etching in 3Vol% natal solution, it’s found that the Mg-contained and Ti-contained inclusions can act as nucleation sits for the intragranular acicular ferrite. These results imply that besides the pinning effect, the oxide of magnesium can also participate in the nucleation for intragranular acicular ferrite. Thus, it may be used in the oxide metallurgy to refine the ferrite microstructure.

Building shape coefficient is an important factor in building energy saving design. In order to analyze the influence of shape coefficient to the energy consumption, a typical residential building is simulated by BECS software to analyze the changing regular patterns of the energy consumption for heating and air conditioning while the building shape coefficient is made different. The relationship between building height and shape coefficient, and the impact of the building plane layout on the energy consumption are also analyzed. The results show that the reduction of shape coefficient is benefit to enhance the effect of energy saving.

A PSO Algorithm with Team Spirit Inertia weight (TSWPSO) is presented based on the study of the effect of inertia weight on Standard Particle Swarm Optimization (SPSO). Due to the theory of group in organization psychology, swarm is divided into multiple sub-swarms and search is run in a number of different sub-swarms which are parallel performed. Try to find or modify a curve which is compatible with optimized object within many inertia weight decline curves, in order to balance the global and local explorations ability in particle swarm optimization and to avoid the premature convergence problem effectively. The testes by five classical functions show that, TSWPSO has a better performance in both the convergence rate and the precision.

The Ni-based WC alloy coatings were successfully fabricated on NAK80 mold steel by Nd:YAG and CO2 lasers. The microstructure and properties of the laser cladded coatings were analyzed by SEM, EDS, XRD and microhardness tester. The results show that phase constituents of both coatings are mainly composed of tungsten carbide (WC+W2C), Cr23C6, NiCr, CrB2 and γ-Ni. The excellent metallurgical bondings have formed at the interface between the substrate and the laser cladded coatings. Dendrite and white and block WC phase were observed in two kinds of laser cladded coatings, but the dendrite in Nd:YAG laser cladded coating is more fine. The microhardness of NAK80 mold steel is greatly improved by laser cladding, however the microhardness of the CO2 laser cladded coating is even higher than the Nd:YAG laser cladded coating.

The Co-based alloy coatings were successfully fabricated on H13 steel by Nd:YAG and CO2laser. The microstructure and properties of the laser cladded coatings were compared and analyzed by SEM, EDS, XRD and microhardness tester. The results show that the excellent metallurgical bonding has formed at the interface between substrate and laser cladded coatings. Cellular crystal at the bonding zone, cellular dendrite at the central zone and reticular equiaxed crystal near top surface were observed in Nd:YAG laser cladded coating, while the typically hypoeutectic character was found in CO2laser cladded coating. Phase constituents of both coatings are mainly composed of Cr23C6, Co3Mo2Si, MoC, FeCr and γ-Co. The microhardness of H13 steel is greatly improved by laser cladding, however the microhardness of the CO2laser cladded coating is even higher than the Nd:YAG laser cladded coating.

With the continuous development of printing technology and printing equipments, the quality of newsprint should be improved to meet with all the real demands. Acrylamide copolymer is used in paper-making as process aid and function aid which can effectively improve paper printing adaptability. Preparation and application of polyacrylamide via aqueous copolymerization was studied as dry strength agent in this paper. The polyacrylamide with middle molecular weight and low viscosity was obtained by reacting acrylamide, cationic monomer [2-(acryloyloxy)ethy] -trimethylammonium chloride and N,N-dimethylaminoethyl methacrylate, anionic monomer itaconic acid, active nonionic monomer N-metholacrylamide and crosslinking monomer 1,3,5-triacryloylhexahydro-s-rine, the copolymer was characterized by FT-IR, charge density and molecular weight distribution. On the basis of internal present situation of pulp, the papermaking system with deinking pulp from office waste paper and white water of 1000-1200us/cm conductivity from paper mill were selected for application research. The results show that when the dosage of acrylamide copolymer is 0.8% to the dry weight of pulp and handsheet basis weight is 60g/m2, acrylamide copolymer can show the superior performance to newsprint and receivable cost for paper mill, fluffing speed, tearing strength and internal bonds are respectively improved by 14%, 20% and 30%.

During the construction of a bridge, the construction procedures may change from the originally designed procedures due to some reasons like the weather. In this paper, the influence of construction procedures on the liner and stress is investigated for a prestressed continuous beam bridge with three spans. Finite element analysis indicated that construction procedures have great impact on the liner control and they affect the middle span and side span differently. Although different sets of construction procedures cause different stress at corresponding construction stages after the cantilever construction is finished, they have no significant influence on the stress of the finally built bridge. Test data agreed with finite element analysis. It is thus the influence of construction procedures on bridge liner control should not be neglected.