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The main objective of this study is to explore prefabricated thermal insulation composite wall’s thermal performance in the project. Using infrared thermal imager and multi-point heat meter takes a test on office building envelope. The test results showed that the composite wall temperature change delay of 3 hours 12 minutes, the temperature change attenuation of 2.5 °C; The composite board exterior wall surface temperature attenuation is larger and the thermal stability of the structure is perfect; thermal bridge is the main reason for reducing the average thermal resistance of the wall.

In order to study the effect of dust removal in the electrostatic precipitator under the influence of change of temperature and air moisture of flue gas, the ultrasonic atomization and electrical heating has been adopted for simulated gas to change its air moisture and temperature. The specific resistance of fly ash of fluidized bed boiler, the V-j characteristics of the precipitator model and the efficiency of dust removal has been tested in gas working conditions. The measured results of dust specific resistance shows that: when the temperature of gas at range of 100°C to 150°C, the specific resistance of dust was lower when the air moisture is at 23.73% than at 5.21%, especially when the gas temperature is below 120°C, the specific resistance of dust reduce more,and it can reach the orders of magnitude at1010Ω·cm when the moisture of 23.73%; then keep the temperature at 150°C and make the moisture increased, the specific resistance of dust is decreased, however it is still more than 1011Ω·cm when the moisture is increased to 23.73%. The measured results of V-j characteristics of the precipitator model shows that: when the moisture keeps at 23.73% and the temperature is below 120°C, the electric field does not occur the phenomenon of anti-corona. The test result of the efficiency of dust removal indicated that: when we make the moisture increased to 23.73% and the gas temperature below 120°C, the efficiency of dust removal shows a significant increase. The results confirmed that we can improve the purification efficiency of high resistivity dust through flue gas humidification and proper temperature maintain.

Transmission spectrum and reflectance spectrum have long been used to characterize gap semiconductor. Transmission spectrum can be measured very directly, but the influence of substrate absorption is often unavoidable. However, when using the reflectance spectrum measurement, the absorption of thin film, substrate absorption, and coherent interference will make the reflectance spectrum much more complicated. In this paper, Considering the absorption of thin film, substrate absorption, and coherent interference, we use the envelope curves algorithm to achieve the calculation formula of refractive index deduced from the reflectance spectrum. Through the analysis of the reflectance spectrum of Ga2O3film, we achieved thickness of the film, refractive index, extinction and absorption coefficient and dispersion constant.

Highly monodispersed ZnO nanorods have been synthesized by the hydrothermal approach with polyacrylamide (PAM) as the template and zinc acetate as the zinc source. Most of these synthesized ZnO rods have diameters of 30 nm~200 nm and lengths of 80 nm~15 μm. The structural characterization of ZnO nanorods was carried out by XRD, TG, FTIR, TEM and SEM. nanoZnO rods can be prepared merely by one step reaction using little template. It indicated that this method can be applied to the commercialization of rod-like ZnO preparation technology.

Arch dam is a water retaining structure which has beautiful bodily form and reasonable structure form, in recent years, arch dam has been widely used. This paper adopts finite element method to carry out three-dimensional finite element simulation analysis for Haierwa reservoir concrete hyperbolic arch dam, researching variation law of the dams stress and displacement in operating process. Research results show that, Haierwa reservoir concrete hyperbolic arch dam is reasonable structure, good mechanical performance, every index meets the requirements for design.

This paper adopt universal finite element calculation software to carry out force analysis for Shayubeigou prestressed reinforced concrete inverted siphon,computer is applied in analysis of prestressed reinforced concrete inverted siphon. Deducing variation law of the inverted siphons stress and displacement in construction process and operating process. The calculation results further shown design schemes rationality and safety. which provide reliable reference of design and construction for the prestressed reinforced concrete inverted siphon.

In this paper, coal-based reduction on flotation middling from iron ore containing carbonate at donganshan was studied, during which the effect of reduction temperature, reduction time, C/O mole ratio and feed layer thickness on reduction process were carried out. The results showed that the optimal reduction conditions required a temperature of 1250°C,a duration of 70min, a C/O mole ratio of 2.0 and a feed layer thickness of 25mm, and the iron powder containing 90.27% Fe with iron recovery of 93.36% was obtained after three stages low intensity magnetic separation, which could be used to make steel. According to the chemical analysis, most of the iron minerals were reduced to metallic iron. Coal-based reduction proved to be an alternative and promising process to conduct the fine particles and powders.

A comparative study on the collecting effect to cassiterite was studied using a new carboxylic acid modified collector DXS and traditional collector salicylaldehyde hydroxamic acid as collectors, respectively. In addition, the relationship between floatability of DXS and crystal structure of cassiterite was investigated. By means of infrared spectroscopy analysis of the cassiterite surface before and after adsorbing DXS molecules, the adsorption mechanisms of DXS on the surface of cassiterite were analyzed.Keywords: carboxylic acid modified collector DXS; cassiterite; flotation mechanism

Energy storage technology plays an important part in wind power generation system integrated with energy storage device. This paper researches on the control strategy of smoothing the output curve of wind power. Take advantage of high power density ultra-capacitor to achieve this objective according to a basic principle that the desired wind power approaches the average value of wind output in the previous period. Meanwhile in order to make the dispatch more flexible, SoC level of ultra-capacitor and fluctuation of wind power are considered to optimize the time constant in real time. The wind power generation system integrated with energy storage device is simulated in the PSCAD/EMTDC software. The simulation results demonstrate the efficacy of proposed control strategy.

In this paper, a JPEG steganalysis algorithm based on locality preserving projection (LPP) dimensionality reduction method is proposed for detecting the unseen stego algorithms. The co-occurrence features are extracted from DCT-DWT domain and dimension is reduced by using the LPP method. For improving the generalization capability of the algorithm, SVDD is used as the classifier. Experimental results reveal the fact that our scheme has better generalization capability and is more effective than others.

DEM matching algorithm without control points is the base for detecting deformation method, the deformation existing in DEMs is treated as gross error. The detectability and locatability of multiple gross errors is very critical according to the surveying error and reliability theory. The interactive observations number (ION) derived from gross error judgement matrix is adapted in this paper. The relationship between zero-column vectors in judge matrix and the rank of the coefficient matrix of DEM matching is discussed in theory, and prove none zero-column vectors exist with real date sets. ION Equal to the number of redundant observations. Experimental results show that DEM matching algorithm has the detectability and locatability of multiple gross errors, and the deformation can be correctly detected by robust estimators in prearranged confidence level.

We investigated the high harmonic generation (HHG) from the interaction of intense femtosecond laser pulse and rare gas in the hollow core photonic crystal fiber(HCPCF) as new optical waveguide materials. The grating-assisted phase matching (GAPM) of HHG in HCPCF is demonstrated to be experimentally feasible and is especially suitable for photon energies in the range of 100~1keV. The conversion efficiency is expected to be dramatically improved for the longer interaction length provided by the very low loss of HCPCF.

In order to further improve the collection efficiency of ESP especially for high-resistivity dust and perfect electrostatic collection theory, how dust layer effects collection efficiency should be revealed more accurately. Taking dust layer as research object, the paper has theoretically analysed the charge distribution of dust layer based on basic principles of electrostatics and Ohm’s Law in order to deduce the formula of the amount of accumulated charge in dust layer. The formula of electric-field strength formed by accumulated charges in collection space was deduced according to the principle of constant voltage and the potential continuity principle of phase boundary. Then the formulas of calculating the effective collecting electric-field and the effective theory migration velocity of charged particles were obtained. The theoretical criterion of occurring back corona was proposed by theoretical analysis of distribution characteristics of electric-field strength in dust layer. Besides that, the elaboration of non-static electrostatic collection theory has enriched and developed the traditional electrostatic collection theory. The paper has player an important role in the design of structure and the selection of operating parameters of ESP, and in the direction to explore the new ways of improving collection efficiency of high-resistivity dust.

The effective areas of triangular lattice photonic crystal fiber (PCF) are analyzed using the finite element method (FEM) both for single-rod and three-rod core PCF. While keeping the normalized wavelength constant, the effective areas of PCF increase with increasing wavelength, it also decrease with increasing ratio of hole diameter over the hole pitch. We also compared the effective area of single-rod core and three-rod core PCF. We find that the effective area of three-rod core PCF is larger than that of single-rod core PCF as the normalized wavelength is small.

The imaging problem of spotlight SAR is converted to a parameter estimation problem of several monochromatic signals in additive white Gaussian noisy condition in this paper. Moreover, a spotlight SAR imaging algorithm based on RELAX is presented in detail. Traditional polar format algorithm and the presented method are applied to spotlight SAR imaging respectively, and the imaging results are compared. Simulation results show that the polar format algorithm doesn’t give satisfactory imaging results, while the proposed method adapts the noisy environment better and obtains better results.

The azimuth resolution of Spotlight SAR is analyzed from the azimuth antenna pattern weighting, and the effect of the azimuth-varying Doppler on Spotlight SAR interferometry is studied. A coregistration algorithm based on adaptive subspace projection is proposed for Spotlight SAR interferometry. In this method, an adaptive factor is introduced to select the sample number of joint covariance matrix based on the coherence value. Moreover, the Doppler centroid drift in the azimuth direction is also considered in spotlight SAR images coregistration. The method is validated with the real data from the GERMAN radar satellite TerraSAR-X.

We numerically investigated the grating-assisted phase matching (GAPM) of high harmonic generation (HHG) from the interaction of intense femtosecond laser pulse and rare gas in hollow core photonic crystal fiber (HCPCF). Our results show that the GAPM of HHG in HCPCF is especially suitable for photon energies in the range of 100~1keV. The calculated modulation period for GAPM of HHG in HCPCF is on the order of micrometer or sub-micrometer. This makes it easy to implement the GAPM of HHG with a counter-propagating modulation laser light in HCPCF. The high harmonic conversion efficiency is expected to be dramatically improved for the longer interaction length provided by the very low loss of HCPCF.

The aseismatic strengthening technique for masonry structure was researched in this paper. The seismic response of a L-type school building with and without isolation system were computed by using software SAP2000. The isolation system were made up of lead rubber bearings or combined Isolation system. The results showed that base-isolated strengthening can reduce not only the translational response but also the torsional response with earthquake. The combined Isolation system was more effetive in decreasing translational response than the lead rubber bearing, but inferior to in decreasing torsion response.

The position of Container Terminal as a transit of a complete logistics system is very prominent. With the rapid development of modern port, the rapid increase in container traffic takes tremendous pressure to terminals. The impact of the restowing problem to the operational efficiency is increasingly prominent. The research on addressing model of the container is important to cut down the restowing rate and improve the operational efficiency. A study is conducted on this in this paper.

A kind of carbon nanotube/expanded graphite (EG/CNT) was used as counter electrodes for the DSSCs following five different weight ratios of 1:0, 1:1, 1:2, 2:1, and 0:1. The impedance spectra and J-V curves were recorded using the Zahner Zennium CIMPS system based on an IM6x electrochemical workstation. The dynamic parameters of the cells were discussed with the intensity-modulated photo current spectroscopy (IMPS) and the intensity modulated photo voltage spectroscopy (IMVS) using white light-emitting diode (75w/m2, 604nm, LED) as the light source.

A three dimensional unstructured model was established and estuaries with different cross sectional divergence rates and different bed form were designed to study the estuary geometric feature effecting on salt-fresh water mixing in estuary. The model dispersing 3d domain into unstructured triangular and/or quadrangular elements, has good flexibility to simulate complex bank. By analyzing the horizontal and longitudinal distribution attributes of velocity and salinity field, the effects of cross section divergence rate, the bottom elevation of mouth and the slope inside estuary on salt water intrusion in estuary are studied. The result could act as design basis for the engineering projects which will change estuary’s bank shape or bed form such as estuary regulation and channel dredging.