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The natural frequency of model was analyzed by finite element software in the first and the result was consistent with the experience formula. Then, time history of ground motion was inputted. The seismic capacity of the structure was analyzed by parameters as structural damage, seismic shear and acceleration. Structural damage in seismic “three levels” and the results of seismic appraisal were consistent. The injury site structure put forward strengthening measure of circle beam and structural column. Scientific basis and technical support for seismic strengthening were provided for Tianjin Western-style dwellings.

With the development of the internet, more and more images appear in the internet. How to effectively retrieve the desired image is still an important problem. In the past, traditional color histogram is used image retrieval system, but color histograms lack spatial information and are sensitive to intensity variation, color distortion and cropping. As a result, images with similar histograms may have totally different semantics. So the spatial information should be included in color histogram. The color histogram based on saliency map approach is introduced to overcome the above limitations. In this paper, we present a robust image retrieval based on color histogram of saliency map. Firstly, in order to extract useful spatial information of each pixel, the steady saliency map of the images is extracted. Then, color histogram based on saliency map is introduced, and the similarity between color images is computed by using the color histogram of saliency map. Experimental results show that the proposed color image retrieval is more accurate and efficient in retrieving the user-interested images.

The synthesis of Lignin Base Epoxy Resin was based on industrial alkali lignin, and lignin-based epoxy resin curing characteristics were analyzed using the thermal weight loss technology under the oxygen atmosphere conditions. In light of the infra-red analysis of raw materials, the curing reaction kinetic parameters of lignin-based epoxy resin system were calculated using the Kissinger-Crane and Flynn-Wall-Ozawa method, and the curing reaction kinetics model of lignin-based epoxy resin system was established. The results showed that the kinetic parameters obtained using two methods were approximate, which validated that the curing reaction was consistent with the principle of the first-order reaction model. Initial curing temperature Ti0=454.88 K, curing temperature Tp0=507.55 K, and terminal temperature Tf0=598.77 K of lignin-based epoxy resin system were obtained when the extrapolation method was applied.

There are many ground source heat pumps in engineering construction application. However, Research on heat exchanger models of single-hole buried vertical ground source heat pump mostly focuses on single U-tube ground heat exchangers other than double U-tube ones in China currently. Compared with single U-tubes, double U-tubes have the heat transfer particularity of asymmetry. Therefore, the use of the traditional single tube models would have large error in the simulation of the actual double U-tube heat exchangers. This paper frames a three-dimensional heat transfer model for the vertical single-hole buried double u-tube heat exchanger in a ground source heat pump system. The model considers the performance of U-bube material and uses a dual coordinate system and makes the control elemental volumes superimposed.

Thermal environmental problems in urban high-rise buildings are prevalent. To analyze the phenomenon, the thermal environment of a typical urban residential subdistrict is simulated by using CFD techniques considering the affects of different type of wall material. The simulation data are carefully analyzed. Some useful results are thus obtained. The direction of the buildings affects air circulation greatly with the north-south orientation having the best effects. Temperature in the subdistrict is about 3~5°C higher than its surroundings because of heat island effects which could be weakened if greening rate of the sbudistrict is increased. Finally, simulation results show that wall materials affect the environment considerably.

Melamine molecularly imprinted polymeric microsphere (MIPM) was initially prepared by two-step seed swelling polymerization methods. Factors affecting the particle morphologies including emulsifier, dispersant, the water-oil ratio, and etc were optimized in order to obtain the MIPMs with a final narrow particle diameter of 3-5 μm. Characterization of the resulted polymeric microspheres was investigated by scanning electron microscope (SEM), infrared absorption spectroscopy (IR), and mercury analyzer (MA), respectively. When the initial concentration of melamine was 1.0 mmol L-1, the affinity capacity of MIPMs was 2.0 times than that of NIPMs. Scatchard analysis suggested melamine were recognized by the prepared MIPMs with two classes of binding sites. The apparent maximum binding capacity and dissociation constant were calculated to be 43.2 μmol g-1 (Qmax1) and 2.2×10-4 mol L-1 (Kd1) for high affinity site, whilst to be 102.3 μmol g-1 (Qmax2) and 1.3×10-3 mol L-1 (Kd2) for low affinity site, respectively. Obvious molecular effects towards melamine were further confirmed by the comparative HPLC experiments using NIPMs and MIPMs as the stationary phases, respectively.

Based on unified strength theory solution of thickness cylinder, according to the introducing concrete strength reduction factor and equivalent restriction factor, this paper deduced the axial compressive bearing capacity formula of concrete-filled double skin steel tubular columns of octagon section. Compared the results of the paper with the experiment results，both coincide in good condition. The results show that the theoretical formula are correct and viable. The theoretical formula is expected to provide a theoretical foundation to the research of concrete-filled double skin steel tubular columns of octagon section.And it provides references for the engineering design.

There is a remarkable interaction when fine particles adsorbed calcium ions in sphalerite / silica system, it is not conducive to mineral flotation. That is the key to how to reduce or eliminate calcium ions for reducing the interactions. This paper focuses on Zeta potential and Zeta potential distribution (ZPD) with single minerals and Mixture (silica/sphalerite=4:1) in gypsum solution, and the interactions of the sphalerite / silica particles was analyzed.

A trigonometric polynomial Coons patch analogous to the standard bicubic Coons patch, with two shape parameters, is presented in this work. The proposeded patch not only has the same properites to the standard bicubic Coons patch, but also can be adjusted by altering values of the shape parameters when the interpolation conditions are fixed. Given proper conditions, the proposed patch can accurately represent torus and ellipsoid.

A quadratic trigonometric B-spline curve analogous to the standard quadratic uniform B-spline curve, with a shape parameter, is presented in this work. The shape of the proposed curve can be adjusted by altering the value of the shape parameter while the control polygon is kept unchanged. With the shape parameter, the quadratic trigonometric B-spline curve can be closer to given polygon than the standard quadratic uniform B-spline curve. The proposed curve can be used to accurately represent the ellipse.

In order to research the weathering characteristics of Tertiary silty Mudstone along Chengnan Freeway, the experiment of the engineering characteristics, the weathering durability, the weathering speed to be done for the different weathering degree silty mudstone. The test result show that when the weathering degree of the rock mass deepen, the content of clay minerals in the rock mass is increase, the activity chemical composition in the rock mass is decrease relatively, the dry density of the silty mudstone is decrease, the total porosity and the water absorption of the silty mudstone is increase, the mechanical properties is weak, the rock mass is soften and collapse easily. The weathering speed of the rock mass with the relevant to the weathering degree and the exposed area of the rock mass.

Highly c-axis oriented ZnO thin films were deposited on n-Si (111) substrate at various oxygen partial pressures by pulsed laser deposition (PLD). X-ray diffraction (XRD), Atomic force microscopy (AFM) were used to analyze the influence of the oxygen partial pressure on the crystallization and morphology of the ZnO thin films. X-ray photoelectron spectroscopy (XPS) was used to analyze relationships between chemical shifts of XPS energy spectra and stoichiometric ratios of ZnO thin films, and quantitative relationships between content of Zn, O and oxygen partial pressures. An optimal crystallized and stoichiometric ZnO thin film was observed at the oxygen partial pressure of 6.5Pa.

A novel flowrate sensor based on a couple of fiber Bragg gratings( FBGs) has been proposed, consisting of fiber grating pressure sensing setup and Venturi tube. The expression of relationship between the flowrate and the wavelength shift difference of the FBGs is derived. The pressure that two sides of the cross section of the aluminum foil tube in the pressure sensing setup results in the distortion of an isosceles triangle cantilever structure. The distortion results in the wavelength shift of a couple of FBGs that are mounted at either side of the cantilever. By monitoring the wavelength shift difference of the two FBGs, the flowrate can be obtained. The cross-sensitive problem of the FBGs sensor can be solved by compensating the temperature effect. The preliminary experiments have been carried out, and the results verify the feasibility of the proposed sensor with a measurement range from 8 to 200 mm/s.

ZnO thin films were deposited on n-Si (111) substrates at various oxygen partial pressures by pulsed laser deposition (PLD). X-ray diffraction (XRD), scanning electron microscopy (SEM) were used to analyze the influence of the oxygen partial pressure on the crystallization and morphology of the ZnO thin films. An optimal crystallized ZnO thin film was observed at the oxygen partial pressure of 6.5Pa. X-ray photoelectron spectroscopy (XPS) was used to analyze the surface components and distribution status of various elments in ZnO thin films. It was found that ZnO thin films were grown in Zn-rich state.

Measurement of fluorescence lifetime plays an important role in fluorescence lifetime imaging technology. If the Time correlated single photon counting method is used to process the signal of fluorescence lifetime images, it can make the real time imaging which have the virtue of high timing resolve and high signal to noise ratio. Multi-wavelength channels are used to record the lifetime simultaneously in four-dimension TCSPC system design. Four-dimension TCSPC imaging can be used to record the photon density over time, wavelength and coordinates of the scanning area. Analysis shows that the counting efficiency and the amount of information in the data can be increased by recording the fluorescence in several wavelength channels simultaneously. Multi-wavelength imaging was also successfully used to separate different fluorephores in stead-state images.

In this paper, the principle of work of aerial work platform truck luffing system is introduced and The mathematics model is established. With Matlab/Simulink software, the simulation model of luffing system is constructed, meanwhile the dynamical characteristics is implemented. With the research work of aerial work platform truck luffing system, this paper provides theoretical foundation for design and improve of luffing system

The effects of various extractants removing Cr from the soil of chromite ore processing residue (COPR) deposited sites were studied in order to select the optimal extractant agent. The effects of this agent on the removal of Cr(VI) and Cr(III) in the contaminated soil were also investigated. The results showed that organic complexing agents had higher removal efficiency than that of inorganic complexing agents due to the high content of Cr(III) in the soil(90.3%). The Cr removal of citric/sodium citrate (mole ratio: 1:1) was 35.95% in 24h. The reason why citric/sodium citrate removed more Cr than other agents is that citric can solubilize the mineral matrix, compete for the surfaces sites to desorb Cr(VI) and remove Cr(III) by its complexation. The concentration radio of Cr(VI) and Cr(III) in the initial soil was 0.11. Thus improving the removal of Cr(III)is the key point of improving the total Cr removal.

The constitutive equations relating cross-sectional loads(forces and moments)to cross-sectional displacements(stretching, bending, twisting) of thin-walled laminated beams with integral shape memory alloy (SMA)active fibers was presented. The variational asymptotic method was used to formulate the force- deformation relationships equations, accounting for the presence of active SMA fibers distributed along the cross-section of the beam. The constitutive relationships for evaluation of the properties of a hybrid SMA composite ply were obtained following the rule of mixtures. The analytical expressions of the actuation components for the active beam were derived based on Tanaka’s constitutive equation and Lin’s linear phase transformation kinetics for SMA fiber. The general form of constitutive relation was applied to the case of stretching-twist coupling, corresponding to Circumferentially Uniform Stiffness (CUS). The present analysis extended the previous work done for modeling generic passive thin-walled laminated beams. Numerical results shown that significant stretching and twisting deflection occur during the phase transformation due to SMA actuation. The effects of temperature on structural response behavior during phase transformation from martensite to austenite are significant. The effects of the volume fraction of the SMA fiber, the martensitic residual strain and ply angle were also addressed