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Electronic structures and electromagnetic wave absorption properties of Fe3Si/polypyrrole (PPy) composites are investigated by using first principles methods based on plane–wave pseudopotential theory. The calculation of electric structures shows that the Fe3Si/PPy composite presents typical metal properties. The real and imaginary parts of the dielectric constant of Fe3Si/PPy are larger than those of Fe3Si. The maximum absorption coefficient of Fe3Si is larger than that of Fe3Si/PPy, and the maximum absorption coefficients of both materials all increase first and then decrease. However, the variation range of the absorption coefficient of Fe3Si/PPy is wider than that of Fe3Si. The reflection coefficient and maximum extinction coefficient of Fe3Si/PPy are larger than those of Fe3Si. The maximum reflection coefficient of Fe3Si/PPy is greater than that of Fe3Si, and the maximum reflection coefficients of Fe3Si/PPy and Fe3Si are 0.81 and 0.91, respectively. In terms of loss function and refractive index, Fe3Si/PPy has more practical value than Fe3Si.

The electronic structure, and magnetic and dielectric properties of Fe3Si@SiO2 core-shell structure with or without SiO2 outer shell cover have been investigated using first principle calculation based on plane-wave pseudo-potential theory. Results indicate that the Fe3Si@SiO2 core-shell structure exhibits a strong interaction between Fe3Si inner core and SiO2 outer shell. The formation energy (Ef) of Fe3Si@SiO2 indicates that it has a structurally stable state at this time. Fe3Si@SiO2 core-shell structure presents typical metal properties and magnetism in the structural optimization process. Furthermore, the total magnetic moment of each atom of Fe3Si@SiO2 core-shell structure is smaller than that of bulk Fe3Si inner core. The SiO2 covered substance also exhibits strong hybridization between the SiO2 shell and the Fe3Si core surface atoms. Thus, the composite structure exhibits strong dielectric polarization response, which further increases the dielectric loss of the material. The calculation results of dielectric properties show that the conductivity and dielectric constant of the core-shell composite are greatly reduced, thereby improving material impedance matching and wave absorption performance.

Based on Solidworks software, the three-dimensional model of two wheels scooter is set up. The finite element model of two wheels scooter is generated. Finite element analysis of telescopic mechanism of bar on two wheels scooter is investigated. The stress and strain of telescopic mechanism of bar is investigated. The stress diagram and the strain diagram are obtained. The method and the result can be used as a reference of innovative design of two wheels scooter.

Based on Solidworks software, the three-dimensional model of two wheels scooter is set up. The finite element model of two wheels scooter is generated. Finite element analysis of driving system on two wheels scooter is investigated. The stress and strain of driving system is investigated. The stress diagram and the strain diagram are obtained. The method and the result can be used as a reference of innovative design of two wheels scooter.

Based on the structure of common scooter, a new portable multifunctional scooter with carrying capacity is developed. Modal analysis of side wheel frame and carrying device on the portable multifunctional scooter is investigated by Solidwoks software. The first five orders natural frequency and major modes of the side wheel frame and carrying device are clarified. The method and the result can be used as a reference of dynamic design and lay foundation for calculation and analysis of dynamic response for the portable multifunctional scooter.

Based on Solidworks software, the three-dimensional model of two wheels scooter is set up. The finite element model of two wheels scooter is generated. Modal analysis of driving system and telescopic mechanism of bar on two wheels scooter is investigated. The first five orders natural frequency and major modes of driving system and telescopic mechanism of bar are clarified. The method and the result can be used as a reference of dynamic design and lay foundation for calculation and analysis of dynamic response for the two wheels scooter.

The characteristics of four-order elliptical gear is analyzed. The parameters of four-order elliptical gear are chosen and calculated. The three-dimensional solid modeling of four-order elliptical gear is achieved. The dynamic model of four-order elliptical gear is established by finite element method and modal analysis of four-order elliptical gear is investigated. The natural frequencies and major modes of the first six orders are clarified. The method and the result facilitate the dynamic design and dynamic response analysis of high-order elliptical gear.

The method of wavelet compression and reconstruction is studied. The wind turbine vibration signal is compressed and reconstructed by wavelet transformation. The compression and reconstruction of wind turbine vibration signal are achieved with different wavelet base. The compression ratio and the compression reconstruction accuracy are analyzed. The method and the result facilitate the choice of wavelet base for transmission of wind turbine vibration signal.

The characteristics of three-order elliptical gear is analyzed. The parameters of three-order elliptical gear are chosen and calculated. The three-dimensional solid modeling of three-order elliptical gear is achieved. The dynamic model of three-order elliptical gear is established by FEM and modal analysis of three-order elliptical gear is investigated. The natural frequency and major modes of the first six orders are clarified. The method and the result facilitate the dynamic design and dynamic response analysis of high-order elliptical gear.

Kinematic characteristics of Hoeken mechanism is analyzed. Variable ratio transmission characteristics of oval gear is obtained. Oval geared Hoeken mechanism is presented. Kinematic characteristics of oval geared Hoeken mechanism is clarified. Eccentricity is optimized. The oval geared Hoeken mechanism with approximate uniform rectilinear motion is designed. The methods in this paper facilitate the innovation design of the mechanism with approximate uniform rectilinear motion.

Through the analysis on e-government business characteristics and its application model, this article proposes that e-government workflow model is the core technology of e-government applications. Hence this paper conducts further study respectively on design state and running state of e-government workflow model. In the design of state, it gives some related definitions about e-government workflow model, such as link, link relationship, receiver, condition, action, event and relations between them. Then gives rise to e- workflow modeling ideas and design framework. In the running state, it focuses on the problems to be solved (deadlock problem) in the actual operation of workflow system. It puts forward related algorithm and data related entities and then discusses about the design of the workflow engine idea.

Kinematic characteristics of double-rocker mechanism is analyzed. Based on variable ratio transmission characteristics of elliptical gear, elliptical geared double-rocker mechanism is presented. Kinematic characteristics of elliptical geared double-rocker mechanism is clarified. Eccentricity is optimized. The elliptical geared double-rocker mechanism with approximate uniform rectilinear motion is designed. The methods in this paper facilitate the innovation design of the mechanism with approximate uniform rectilinear motion.

Kinematic characteristics of Hoeken mechanism is analyzed. Variable ratio transmission characteristics of elliptical gear is obtained. Elliptical geared Hoeken mechanism is presented. Kinematic characteristics of elliptical geared Hoeken mechanism is clarified. Eccentricity is optimized. The elliptical geared Hoeken mechanism with approximate uniform rectilinear motion is designed. The methods in this paper facilitate the innovation design of the mechanism with approximate uniform rectilinear motion.

The geometry relationship of parameters in double-rocker mechanism is deduced. Utilizing Euler-Savary Formula, the double-rocker mechanism with horizontal uniform rectilinear motion is designed. The horizontal uniform rectilinear properties of the mechanism are analyzed. The mapping principle between parameters and the mechanism output motion is clarified. And the design method and principle for double-rocker mechanism with horizontal uniform rectilinear motion is proposed. The results in this paper facilitate the innovation design of double-rocker mechanism with horizontal uniform rectilinear motion.

The positions and orientations of the tool and workpiece are analyzed for machining axisymmetric aspheric concave surface and the position and orientation matrixes of the workpiece and the tool are obtained. The relationship between the tool and the workpiece is set up by using the method of coordinate transformation. The basic modules and the necessary motions for generating axisymmetric aspheric concave surface are clarified. And the possible structural configurations of the machine tool are proposed and optimized. The results in this paper facilitate the innovation design of a machine tool for generating axisymmetric aspheric concave surface.

A Pilot-scale study was conducted to treat municipal wastewater by Biological-Ecological filter (BEF), which is composed by anaerobic hydrolysis pool (AHP), high load biological filter (BF) and vermifilter (VF). The results demonstrated that when the influent concentrations of COD and NH3-N were in the range of 190~300 mg/L and 25~35 mg/L, respectively, the effluent concentration of them ranged from 45 to 65 mg/L and 8 to 20 mg/L with the average removal efficiency of 73.6% and 50%, respectively. Meanwhile, the effluent average SS concentration was less than 15 mg/L. The effluent quality could steadily meet the second level criteria specified in Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB 18918-2002) in China. The removal performance of fine zeolite was significantly better than the coarse one and heightening packing layer had little effect on the removal of COD and NH3-N. This study verified that BEF system for municipal wastewater treatment was feasible.

Sinperca chuatsi usually refuses eating dead bait or man-made feed due to its specific feeding habit. It was showed that some S. chuatsi could be induced to take lifeless bait with domestication gradually after long-term of cultivation. High cost, serious pollution, severe diseases, and other problems of S chuatsi cultivation can be solved effectively by selecting those liable to domestication via molecular marker and treating them with artificial feed on a large scale. Lipoprotein lipase, one of the key enzymes in lipoprotein metabolic processes, provides energy by catalyzing the oxidation of triglycerides lie in the core of chylomicron and very low density lipoprotein (VLDL) into glycerin and fatty acid, and saves energy. In order to search the distribution of the alleles and genotypes of lipoprotein lipase gene (lipoprotein LPL) gene in two feed habit domestication phenotype populations, SNP genetic polymorphisms in 6 and 7 introns and 6, 7, and 8 exons of LPL in S. chuatsi were analyzed by PCR product sequencing method. Three SNPs A25T, G26T, and C29G were detected, two of which were non-synonymous mutations. It was indicated by Chi-square test that the analysis between domesticated and undomesticated populations show no significant difference (P>0.05) between the three SNPs and feed habit. However, diplotype 2 in the two population showed significant difference (P

Boundary labeling connects each point site in a rectangular map to a label on the sides of the map by a leader, which may be a straight-line segment or a polyline. In the conventional setting, the labels along a side of the map form a single stack of labels in which labels are placed consecutively one by one in a sequence, and the two end sides of a label stack must respect the sides of the map. However, such a setting may be in conflict with generation of a better boundary labeling, measured by the total leader length or the number of bends of leaders. As a result, this paper relaxes this setting to propose the boundary labeling with flexible label positions, in which labels are allowed to be placed at any non-overlapping location along the sides of the map so that they do not necessarily form only one single stack, and the two end sides of label stacks do not need to respect the sides of the map. In this scenario, we investigate the total leader length minimization problem and the total bend minimization problem under several variants, which are parameterized by the number of sides to which labels are attached, their label size, port types, and leader types. It turns out that almost all of the total leader length minimization problems using nonuniform-size labels are NP-complete except for one case, while the others can be solved in polynomial time.

Sinperca chuatsi usually refuses eating dead bait or man-made feed due to its specific feeding habit. It was showed that some S. chuatsi could be induced to take lifeless bait with domestication gradually after long-term of cultivation. High cost, serious pollution, severe diseases, and other problems of S chuatsi cultivation can be solved effectively by selecting those liable to domestication via molecular marker and treating them with artificial feed on a large scale. Lipoprotein lipase, one of the key enzymes in lipoprotein metabolic processes, provides energy by catalyzing the oxidation of triglycerides lie in the core of chylomicron and very low density lipoprotein (VLDL) into glycerin and fatty acid, and saves energy. In order to search the distribution of the alleles and genotypes of lipoprotein lipase gene (lipoprotein LPL) gene in two feed habit domestication phenotype populations, SNP genetic polymorphisms in 6 and 7 introns and 6, 7, and 8 exons of LPL in S. chuatsi were analyzed by PCR product sequencing method. Three SNPs A25T, G26T, and C29G were detected, two of which were non-synonymous mutations. It was indicated by Chi-square test that the analysis between domesticated and undomesticated populations show no significant difference (P0.05) between the three SNPs and feed habit. However, diplotype 2 in the two population showed significant difference (P0.05) by assembling different genotypes of the three SNPs into five diplotypes. Polymorphic analysis of partial fragment of LPL genome in S. chuatsi was accomplished successfully. Therefore, LPL gene can be considered as a candidate gene and genetic marker for feed habit domestication in S. chuatsi, which lays the foundation for the work of molecular marker and selecting breed, which has extensive application prospect.