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The printing machine is a sort of large-scale equipment characterized by high speed and precision. A fault diagnosis method based on kernel principal component analysis (KPCA) and K-means clustering is developed to classify the types of feeding fault. The multidimensional and nonlinear data of printed image could be reduced by KPCA to make up the deficiency of the traditional K-means clustering method. In this paper, it is experimentally verified that the classification accuracy of the combined method is higher than the traditional clustering analysis method in feeding fault detection and diagnosis. This method provides a shortcut for the determination of fault sources and realizes multi-faults diagnosis of printing machinery efficiently

As an important application area of field-bus system, UPS require high reliability and real-time property. Standard CAN protocol in application layer have not been proposed in home and abroad. Based on CAN-bus 2.0 A/B, this paper designed UPS-CAN protocol which conform to general UPS parallel system and proposed a novel network management system (MSN) during development of module UPS parallel system. Experimental results proved the reliability and real-time property of UPS-CAN which meets the requirement of UPS parallel communication system.

Possible ways to remove fluoride from phosphoric acid are extraction,but there are always generated a second organic phase ,where still have small amounts of impurities such as fluoride,sulfate,iron,aluminum and heavy metals. The traditional process using pure water or dilute phosphoric acid washing the organic phase to get phosphoric acid ,but the impurities removing rate is not obvious.This study explore a new way to changes the washing detergent,using dilute alkali solution to reduce fluoride content of stripping in phosphoric acid.The optimization of experimental conditions is dilute alkali mass fraction 20%,dosage 0.4%,temperature 45°C,the defluorization rate can be 67.75% and phosphorus pentoxide yield rise to 95.50%.This study provides a new idea to improve defluorination rate in industrial production.

The surface modification process for cotton fabric which was oxidized first, and then crosslinked with collagen was studied. The optimum oxidation process was as follows: concentration of sodium periodate 0.6g/L, time 2.5h, temperature 40°C, ratio of water and cotton fabric was 100:1. The method for surface modification of cotton fabric was determined from comparative analysis, and the optimum process: collagen solution concentration 6%, glutaraldehyde concentration 5%, reaction 40min at 30°C, ratio of water and cotton fabric was 100:1. Compared with original cotton fabric,the breaking strength and elongation of collagen modified cotton fabric decreased, while the dyeing percentage with acid dyes was increased and this means the surface of modified cotton fabric was covered with a large component of collagen.

The statistical histogram algorithm is one of the common background update algorithms. Considering the statistical histogram algorithm disadvantages of large complex computation, the paper proposes an improved method named fixed window statistical background updating algorithm. The algorithm sets a window which contains N records for each pixel point firstly, every record records value in the permissible range of error and the number of pixel point occurrence, and then counting pixel values for every record through statistical histogram algorithm. When the window is full, the new pixel values will replace the smaller counting, while the pixel which counting larger will be adaptively updated by adaptive background updating formula. The experimental result shows that this method has a high real-time performance and robustness in background updating.

After the construction project evaluation and implementation of the entire project an indispensable part of the process, and establish a sound, scientific index system for the scientific evaluation of the results obtained have a pivotal role in the project. This paper discusses the method of establishing evaluation system after construction projects, and gives a more scientific and comprehensive indicator system: After the implementation and management, project operations conducted from four economic projects, project evaluation and analysis of the impact and sustainability of projects establish the sub-indices, including duration of the project, project quality, with a total investment control, project profitability, solvency, environmental impact, economic impact, social impact, policies and projects for sustainable development and social factors, financial factors, social factors, a number of technical factors. Each sub-index and a scientific decomposition.

The accuracy of the results of the evaluation after the construction project is largely dependent on the choice of the evaluation method is reasonable and scientific. In this paper, the current methods for the evaluation of projects for a more systematic study were compared and analyzed; and proposed the construction of the factor analysis method for the analysis of project evaluation, and gives two reasons for the application of this method .

To more accurately learn reliability on anti-overturning stability for a truck crane, a parametric multi-body dynamics model is built in a dynamic software environment with overall key parameters as design variables. On this basis, stability criteria of this truck crane are established according to the working conditions and crane dynamics simulation results. After a truncated normal distribution sampling method is given for design variables which will effect on truck crane's stability, the reliability analysis of this truck crane is done via Monte Carlo method. The result indicates that the truck crane's stability reliability is 0.9998 in the most dangerous working condition. Analysis shows that the reliability calculation of truck crane anti-overturning stability is feasible using modern multi-body dynamics and Monte Carlo method, and the results are more accurate than conventional safety factor method.

With the rapid development of global electricity, our country has to study the smart grid in the background of the global development. We study the innovation of smart grid based on the engineering theory of service, and hope to provide a reference for smart grid research and the future development of the grid. Therefore, our country can adapt to the future development direction of the global market and service economy led.

Provided by ALTERA FPGA/CPLD Quartus II development software development platform. programmable timer/counter 8253s functions and internal circuitry as the basis, combined with programmable gate array (FPGA) products FLEX10KE characteristics, using VHDL hardware description language and schematic Figure two ways 8253 for hierarchical, modular, parameterized logic design. The completed design will be configured to the chip of FLEX10KE,and Proved to be correct.

Preparing of cool wool from coarse wool fiber is a feasible and effective method. The preparation principle, process and properties of cool wool fiber was studied during chlorination treatment with sodium hypochlorite. The optimum chlorination treatment process was as follows: concentration of sodium hypochlorite at 4g/L, concentration of sulphuric acid at 20g/L, time 15min, temperature 20°C to 25°C, ratio of water and wool fiber was 50:1. Compared with original wool fiber,the surface of cool wool only retained scales roots and the cuticle becomes thinner. Handle, softness, whiteness, luster and the anti-shrinkage properties were improved, the breaking strength is decreased about 5% to 8%.

The engineering construction item has a period to grow, the complicated degree is big, invest a great etc. characteristics.Many risk factors exist in the process of the engineering Construction. It will influence engineering item smoothly progress If can not effectively work well to guard against in time. Therefore, it have important meaning to strengthen a construction engineering risk management work. This text will carry on certain analysis to each risk factor of construction engineering item, and inquire into further how science, effectively strengthen a construction engineering risk management to work, then promise engineering item construction smoothly progress.

In order to simulate the dynamic trends of the influencing factors of water resources gap and periodic characteristics of the related factors, this paper establishes regional transition model and Error Correct Model as well as state-space model, whose parameters are used to measure the influences and trends. Empirical results implicit that these models fit sample data very well and some useful conclusions can be drawn from these parameters estimation. Different functions of influencing factors between periods of short and adequacy of water supply are showed. It is necessary to arrange consumption use rationally because of its greater percentage when water was scarce. The increasing consumption use becomes the main factor of water shortage.

Gunpowder was released in an instant when the pill fly out of the shell during the firing, and then formed a complicated flow fields about the muzzle when the gas expanded sharply. Using the 2 d axisymmetric Navier-Stokes equation combined with single equation turbulent model to conduct the numerical simulation of the process of gunpowder gass evacuating out of the shell without muzzle regardless of the pill’s movement. The numerical simulation result was identical with the experimental. Then simulated the evacuating process of gunpowder gass of an artillery with muzzle brake. The result showed complicated wave structure of the flow fields with the muzzle brake and analysed the influence of muzzle brake to the gass flow field distribution.

Roller-mark is a common problem in offset printing and its solution method is important for printing. A new detecting method of texture analysis was given in this paper. In this study, printing image was acquired with high-speed CCD. Compared the difference between printing image and standard image, a defective image was obtained. Then the reason of roller-marks was given by the texture recognition of defect image. Finally, experiments were taken to prove the feasibility and effectiveness of this new method for the roller-marks diagnosis in the offset printing machine.

The forecasting precision of short-term wind speed is not high for its chaos and time-varying. Aimed at the problem, the novel data space is reconstructed with the best embedding dimension and time delay according to the phase space reconstruction. On the basis, neural network (NN) is used as the modeling tool with the novel sample data. Meanwhile, the structure of NN is confirmed compared with the others on the precision. In the end, the model of short-term wind speed is able to be obtained. The results show that the method is available and the Mean absolute error (MAE) is decreased to 16.2% for 2 hours.

The thermal conductive silicon rubber have been prepared by using aluminum nitride as filler. The morphology and dispersion propriety of the filler were investigated by Scanning electron microscopy. The thermal conductivity of the composites was analysized by thermal measurement system. The results show that The larger particles give rise to a higher thermal conductivity of composites, at the same time the thermal conductivity of the composites increase with increase of aluminum nitride filler fraction. When the particle size is 60 nm, the thermal conductivity of composites at 40% volume fraction is about 3.5times that of pure silicon rubber matrix.

carbon nanotubes were synthesized by pyroysis method using copper nanoparticles as catalyst. The structure, phase composition and hydrogen storage capacity were investigated by TEM, XRD spectra and Electrochemical System. The results show that the diameter of carbon nanotubes is 200-500nm, The P-C-T curve of adsorbing hydrogen of samples was measured in the pressure up to 12 MPa at room temperature. we show that a SWNT can strongly adsorb up to 8-wt% hydrogen. These results advance our fundamental understanding of dissociative adsorption of hydrogen in nanostructures and suggest new routes to better storage and catalyst materials.

An improved artificial immune algorithm is proposed for geophysical P-wave amplitude variation with offset (AVO) inversion. In this paper, the algorithm is described and implemented. The orthogonal crossover is used to generate the initial population and the elitist-crossover is adopted to add the good patterns of the population. The hybrid mutation method is presented to increase the ability of local and global optimization. The improved immune algorithm is then applied to earth interface models of Mexican gulf for AVO inversion. The experimental results show that the improved algorithm is of high precision than the traditional immune algorithm.

The paper aims at the simulation on double tank water level control based on MATLAB .Double tank water level control belongs to large time delay system. In this paper, adopted PID method to control the system, Then, fuzzy PID control method was used to adjust this second-order system. And the simulation model of this system is built with MATLAB Fuzzy and SIMULINK. And at the end, analysis the system stability ,reaction velocity and so on.

As the urban new developing strategy and mode, low-carbon economy meets the requirements for the sustainable development in the urban area. On the basis of development analysis for the low-carbon economy home and abroad, this paper illustrates the challenges that urban area meets in the process of low-carbon economy and sustainable development by taking the example of Baotou, as well as making proposals and suggestions accordingly.

Ethanol extracts from Hohenbuehelia serotina and Armillaria mellea fruit bodies were prepared and investigated for their antioxidant capacities in three different assays, namely, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, reducing power and chelating ability on ferrous ions. Among the two mushrooms, ethanol extracts from A. mellea was more effective than that from H. serotina in scavenging DPPH free radical ability, while ethanol extracts from H. serotina was some higher than that from A. mellea in reducing power. With regard to chelating effect on ferrous ions, at 5 mg/mL, chelating ability of ethanol extracts from H. serotina were 43.17 %, while that from A. mellea was 46.54%. It can be concluded that ethanol extracts from A. mellea and H. serotina were good in antioxidant properties.

A BLDCM drive system based on Z-source converter is proposed in this paper, it can be integrated to control DC bus boost and BLDCM speed by Z-source transformation technology, which not only improve energy efficiency but also raise the system security. The algorithm of PWM is applied to control Z-source inverter, which is simulated by Matlab/Simulink, the results are shown to verify the features of the Z-source inverter for BLDCM drive system, and confirm that the method is correctly and availably.

Aim at a current our country the construction invested in the middle of the item an existent problem to carry on analysis, to domestic and international construction item behind evaluated a theoretical development to make to elaborate, and analyze our country behind evaluate current performance present condition of mechanism and the blemish of existence, put forward some improvement suggestions.After pointing out at the same time evaluate is the important link that constucts an indispensability in the item period, have count for much meaning to decision level and investment efficiency that raises item, at our country its development should have vaster prospect.

We prepared Solid silicon nitride nanowires using carbon nanotubes as precursors., Si and SiO2 were used as raw materials,the reaction was carried out in ammonia atmosphere The structure, phase composition, ESR properties and oxidation resistance of the sample were investigated. The results showed that the sizes of the nanorods are 60–80 nm in diameter and up to several microns in length. In the products α-Si3N4 is the main component; the FTIR spectra of the silicon nitride nanowires have blue shift phenomena;The ESR properties show that the as made materials contains a large number of unpaired electrons

We synthesized carbon-coated iron magnetic nanoparticles by a low cost method using Ferric nitrate as the iron precursor and starch as both reductive agent and carbon source under H2 atmosphere. The structure, size distribution, phase composition, magnetic properties and oxidation resistance of the particles were investigated by transmission electron microscopy, X-ray diffraction, vibrating sample magnetometry and differential scanning calorimetry. The results show that the carbon-coated iron nanoparticles are spherical particles with a diameter of 20-40 nm. They are particles of core-shell structure with an iron core inside and an onion skin carbon layer outside, carbon layer can protect inner iron core from been oxidized, the hysteresis curves show that they are super paramagnetic materials. At the same time the annealing can change the magnetic properties of carbon coated iron nanoparticles.

In this paper, the silicone rubber composed of carbon fibers was prepared. The influence of different concentration of carbon fibers on the conductivity, electromagnetic shielding interference effectiveness property of the silicone rubber was discussed from the point of view of condition of carbon fiber and silicone rubber. The results showed that there existed the extreme conductivity and shielding effectiveness (SE) across the tested frequency range from 2.6 GHz to 3.95 GHz of silicone rubber composites filled with carbon fibers. When the content of the carbon fibbers was 50 parts per hundred of rubber (phr), the SE values of composites were typically above 63 dB and close to the extremum. The compact packing structure of carbon fibers does not play an important role in improved the conductivity of composite. The SE of the composite depends on the conductivity of composite.

The detection of localized defects such as cracks and corrosion in pipes using guided waves has been shown to be an effective nondestructive evaluation technique for structural health monitoring (SHM). Cross borehole tomography in seismology is introduced into the guided wave inspection of a pipe when the pipe is considered as an unwrapped plate. Guided waves propagating in pipe with a crack defect are simulated using the finite element model and the arrival times for the fastest modes are extracted and sent to the tomographic algorithm. The tomographic reconstruction is based on the simultaneous iterative reconstruction technique (SIRT). For some cylindrical shell geometries such as stacked storage tanks, access to the entire circumference of the structure could be impractical or even impossible, three different image fusion techniques are used to enhance the image equality reconstructed from the incomplete datasets. The results show that the defect is more pronounced after imaging fusion.

Guided wave tomography has shown great potential for quantitative nondestructive evaluation in structural health monitoring. An improved simultaneous iterative reconstruction technique (SIRT) combining genetic algorithm (GA) is presented in order to improve image quality of guided wave tomography. The simulated reconstructed images of flawed plate and pipe using usual SIRT and improved SIRT methods have been compared quantitatively and qualitatively.