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Ce3+doped cubic KLaF4system was synthesized by co-precipitation method. The sample was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-Vis spectrophotometer and fluorescence spectrophotometer. The result indicated the nanoparticle diameter of KLaF4:Ce3+was 12.5 nm. The KLaF4:Ce3+had a stronger absorption at 250 nm, which could be explained by d elecronic transition of Ce3+. The maximum emission peak of KLaF4:Ce3+was 355 nm in its luminescent spectrum, and emission band of Ce3+also belonged to 5d→4f transition.

The development of science and technology has become an inevitable trend of economic globalization, more and more enterprises realize that the competition between enterprises has already becomes a complex systems engineering, and in the process, the original management pattern gradually exposed the shortcomings, should be replaced by the information management mode. So far, the most complex ERP is the enterprise information management system, it for the enterprise information management provides a new train of thought, to optimize enterprise resource allocation efficiency, strengthen the core competitiveness of the enterprise. This paper analyzes the application of ERP system in the process of enterprise shown, the characteristics of problems including the system in use process. This article selects the typical enterprise ERP application case study, based on the enterprise ERP implementation methodology reference model quickly, for the related industries, enterprises implementing ERP, and equipment asset management problem of study for reference.

Emergency communication refers to the appearance of natural or man-made sudden emergencies, which comprehensively use various communication resources to guarantee the emergency rescue and necessary communication. Emergency communication system requires not only mobile, but also rapid response and wide range. According to these requirements, the paper establishes a process model based on Object-oriented Petri net. The application shows that the model can be used to conveniently describe the dynamic and uncertainty characteristics of emergency communication tasks, which can reduce the complexity of process organization and provide the conditions for fast restructuring and integrating functions of module tasks.

In order to get rid of noise from the angular displacement of the crank rocker mechanism, the wavelet transform method is introduced. After the noise corresponds to the high frequency band of wavelet domain of the signal and the signal corresponds to the low frequency band of wavelet domain of the signal, the signal is decomposed into four layers, and the high frequency brand is set zero. The test results show that this method was most ideal for the de-noising effect on displacement signals, which is able to not only retain valid signals but to effectively remove the noise.

From a theoretical perspective, this paper develops a systematic approach to analyze the transient characteristics of the low voltage ride through in three-phase short-circuit rotor current. Firstly, the steady state current mathematical model of the system is described. And then, the short-circuit rotor current dynamic characteristic during the low voltage fault is analyzed, the resistance value and switching strategy of crowbar are discussed. Finally, the simulation results and the theoretical analysis manifest that appropriate crowbar reactance value and switching time can improve LVRT control characteristic and grid stability.

Current attenuation rate plays an important role for battery rapid charging.This paper studied the relation between state of charge (SOC) and rebound voltage. Then the fuzzy logic control system with single-input and single-tap has been designed based on SOC and initial charging current.The results showed the maximum current attenuation rate can be achieved when the relationship of initial current and SOC arrived at an optimal value.

In this work, potassium tantalate (KTaO3) particles were synthesized using a low-temperature hydrothermal method. The phase structure of samples prepared was performed by X-ray diffraction (XRD). The result revealed that it belongs to cubic crystal. The electrochemical behaviour of a KTaO3film coated electrode was investigated in 0.1 mol dm-3KCl containing 5 mmol dm-3K3Fe (CN)6with cyclic voltgrammetry (CV). The CV results indicated that the KTaO3film coated electrode exhibited excellent electrochemical stability. The electrochemical reaction of K3Fe (CN)6on the KTaO3film coated electrode was a diffusion-controlling process.

In order to reduce costs and improve crop yields effectively, a greenhouse environment monitoring system based on ZigBee and GPRS technology is designed. In the system, ZigBee wireless sensor module is used for data acquisition of soil moisture, precipitation, nitrogen concentration, temperature and barometric pressure data etc. The information is sent to a remote monitoring center through GPRS, Instructions is regulated and take corresponding measures according to the received information. The system can collect and monitor the parameters of the greenhouse environment at a real time. This has important implications for the development of agriculture automation and agricultural production levels.

In this research, the primary study in extracting technologies of Tea polyphends was finished. On the basis of the water lixiviation by orthogonal optimization method, extraction process of TP by microwave extraction was optimized. The best combined condition of the water lixiviation as follows: liquid-lolid ratio 25:1, extraction temperature 95°C , extraction time 20min,Under this conditions, the yield of TP is 13.993 %.And the best combined condition by microwave extraction: liquid-lolid ratio 35:1, microwave power 750 W, extraction time 18min, and the yield of TP is 20.3023 % through duplicated experiment. The results showed that compare with water lixiviation, the yield of TP was enhanced by 6.3093 % by microwave method. Meanwhile, the extraction time by microwave method was reduced greatly.

Taken into account the effect of pile partially separated from soils, the dynamic stiffness and damping of pile in horizontal vibration is caculated by using the theory of computation about the mixed boundary value problem of circular holes radiation stress at an infinite plane and the theory of elastic waves, and the Fourier expansion method. The calculated results based on this paper are compared with the calculated results of the other literature. It is showed that the calculated results considering the influence of pile-soil separation are less than that of the other literature, which the bonding of the pile to the soil was assumed, and are in good agreement with experiments.

With the rapid development of network information technology, much attention has been paid to the database content security problems,such as how to prevent data theft, illegal copying, certification of copyright, etc. In order to protect the database copyright, digital watermarking technology is becoming a new research hotspot. In this paper, first of all, on the basis of summary current development of data and database watermarking technology, and then introduces genetic algorithm in data watermark technology, finally validates the effectiveness of the model with an example.

Polycrystalline CuIn(Se,S)2 (CISS) thin films with chalcopyrite structure were synthesized by sol-gel spin-coating method. Sequential reduction, selenization and sulfurization treatments were performed with hydrogen, Se and H2S vapor, respectively. The effects of different sulfurization times on the films were also studyed. X-ray diffraction (XRD), and SEM analysis have been employed to examine the structural properties and surface morphology of polycrystalline CISS thin films. The experimental results demonstrated that the obtained CISS had good crystallinity and uniformity.

We studied a new Heusler alloy V2CoSi with Hg2CuTi-type structure by first-principles calculations. The electric structure and magnetic properties have been investigated. The alloy has a total magnetic moment of 1.00μB per unit cell on first-principles calculations which is in agreement with the SlaterPauling (SP) rule. The magnetic moment of atom Co is 0.38μB and the magnetic moments of V(1) atom and V(2) atom are 0.80μBand-0.24μB respectively, so the alloy is a ferrimagnetism.

There were two controlling factors, which should be kept balance of raw input and energy during titanium slag smelting in closed high power direct current electric arc furnace, DC furnace for short. The first factor contains compositions and ratio of input raw materials. Compositions of the raw could influence the progress and technical indicators of DC furnace smelting, and on the meanwhile, it could determine the compositions of impurity and contents of TiO2 in titanium slag. On the other hand, the ratio of input infected the compositions of the slag, while too much anthracite would disadvantage to produce high quality slag because of impurity being reduced continually. Meanwhile much more low-state titanium would be generated. The second factor was an important one that energy equilibrium, which influence the production safety of DC furnace. It could keep balance of input and output energy, while the heatloss was 4.971 MVA. While the ratio of anthracite remained the same, the energy would effect slag viscosity and equilibrium of freeze lining directly. The energy input higher than smelting need would result in burnthrough of furnace wall and hearth, on the contrary, lower than smelting need would bring about slagging difficulties. Consequently, raw input and energy must be kept dynamic balance in order to achieve high quality titanium slag and protect freeze lining.

Cybersecurity, as stated in the 2010 National Security Strategy of America, threats represent one of the most serious national security, public safety, and economic challenges we face as a nation. This paper examines the cybersecurity situation that the nation faces. Based on this, the vulnerabilities present in information systems and systems supporting critical infrastructure to cyberattacks are discussed. The argument is presented that Chinas internet censorship techniques have improved that nations Cybersecurity, which could affect the outcome of a conflict in cyberspace. The key future features of the Cybersecurity in China are put forth at the end of the treatise. The author believes such analysis can credibly help the establishment of the national Cybersecurity strategy.

In this paper, we studied the seasonal variation of rainfall and runoff of Yuanjiang-Red River Basin in Yunnan during the last ten years and obtained the seasonal change of rainfall on spring, summer, autumn, winter. But we found some fluctuations in 2002, 2003, 2004, 2010, then analyzed the reasons of fluctuations. In these years, the basin emerged different levels of disasters. Meanwhile, runoff also had the variation, and there were some similarities between rainfall and runoff. The research on seasonal variation is significant for hydrological monitoring.

This paper presents a research on the evolution of urban color in Jinlang District, Shenyang, using GB/T15608-1995 China Color System and China Building Color Card. Also, we have analyzed the cause of this color evolution considering the progress of urban construction. The study has shown that the color in this area is characterized by low chroma and mild warm tone. After entering the new century, however, a trend towards low chroma, high brightness and yellow color is going on, with some original features diminishing, due to the development of city construction.

This study investigates the influence of material nonlinear in slender reinforced concrete (RC) columns dynamic second-order effects under seismic load. The stiffness reduction coefficient is adopted in this paper. To identify the significance of various effects in terms of the dynamic second-order effects of the slender RC columns, nonlinear dynamic analyses are conducted for different periods and stability coefficients of simulated models with rare occurrence earthquake. On the basis of the obtained numerical results, the influence of material nonlinear for dynamic second-order effects are reviewed.

The paper studied the dynamic second order effects response of the single-degree-of-freedom (SDOF) system under vertical earthquake ground motions. The following achievements have been made: (1) the motion equations under vertical earthquake loading with second-order effects were established; (2) through numerical analysis, the regular patterns of structural dynamic second-order effects subjected to vertical earthquake loading are uncertain.

The complex fluorides BaCoF4 and BaCoF4: Ce3+ were synthesized by reflux method in ethylene glycol and characterized by means of XRD, TEM, XPS, UV-VIS and Fluorescence Spectrophotometer. In addition, the photocatalytic degradation property of BaCoF4: Ce3+ was investigated. The results indicated that the mean particle diameter of BaCoF4 was 54.6 nm. Only adsorption oxygen (α oxygen) existed on the surface of BaCoF4 and the content of surface oxygen was 5%. The BaCoF4: Ce3+ had a stronger absorption at 250 nm, which could be explained by d electronic transition of Ce3+. The maximum emission peak of BaCoF4: Ce3+ was 361.8 nm in its luminescent spectrum, and emission band of Ce3+ belonged to 5d4f transition. Meanwhile, the degradation rate of acid red 3B by BaCoF4: Ce3+ reached 98.7% after being lightened for 2 h by a 450 W high pressure mercury lamp.

The structural character of breech mechanism is studied and analyzed in order that the virtual prototype model is the best. By the CAD software Pro/Engineer the XX breech mechanism virtual prototype is built. At first, the 3D modeling of the XX Breech Mechanism is generated with the parametric design and virtual assembling, and experiment platform of virtual prototype including all kinds of conditions is set up. At last, the quantitative analysis is performed on the above experiment platform, the experiment resulting is accord with specification data by and large, which validates that the designed breech mechanism virtual prototype is proper and appropriate.

S elbow in Zhijing River is one of the key parts in the East Gas Transmission Pipeline Project. It brings a great deal of uncertainty and risk factors for pipeline pigging operations. By analysis on dynamic of pig pigging and the impact over bending, this paper established the finite element model, simulated pigging process on the condition that the operating parameters of the pipeline pigging operations were given, analyzed the relationship among pipeline pressure, foam pigging speed and pipe stress, then obtained the security of pipeline pigging operations.

A non-vacuum process for fabrication of polycrystalline CuIn(Se,S)2 (CISS) thin films with chalcopyrite structure were synthesized by sol-gel spin-coating method using nitrates as precursor for low-cost photovoltaic applications. Sequential reduction, selenization and sulfurization treatments were performed with hydrogen, Se and H2S vapor, respectively. X-ray diffraction (XRD), SEM and EDS analysis have been employed to examine the structural properties, surface morphology and atomic concentrations of polycrystalline CISS thin films. The experimental results demonstrated that the obtained CISS had good crystallinity, uniformity and near stoichiometric composition.

Issues of environmental protection and sustainable development are gaining an increasing importance in everyday life, and nowhere is this more than in the field of Materials Science and Engineering. The alga is the most common phytoplankton, identifying them can estimate the community structure and distribute status of ecosystem in the sea area and realize the inspecting and comprehensive father of sea. In this paper, the three dimension fluorescence spectra and principal component analysis method is combined to identify the ocean phytoplankton. Aiming at the east China sea, adopt the selection of common seaweed three-dimensional fluorescence spectrum of first principal component scores spectrum as bacillariophyta and pyrrophyta identification features diatoms and spectrum, established the phytoplankton fluorescence features spectrum library. On this basis, the SVM classifier is used to identify the kinds of the phytoplankton. The accuracy of the experimental results recognition is for 95%.

The extraction of flavonoids from clovers was optimized to maximize flavonoid yield Y in this study. A central composite design of response surface methodology involving extracting time, liquid-solid ratio, extracting temperature and ethanol concentration was used, and second-order model for Y was employed to generate the response surfaces. The optimum condition for Y was determined as follows: extracting time 24min, liquid-solid ratio 20, extracting temperature 80°C, and ethanol concentration 72%. Under the optimum condition, the flavonoid yield was 2.49%.

The contrast is low, and the noise is strong in infrared images, which go against defects judgment and recognition. In order to resolve them, limitations of common methods were analyzed, then, according to characters of infrared images and processing target, grayscale value adjustment method and low pass filter method was introduced. Designed image enhancement steps, and it was applied to process thermal image. In process of index low-pass filtering, the cut-off frequency selection was studied. And, it was found, when it was 40, the effect was ideal. Compared the original image with image after treatment, the validity of this method was verified. There an effective way was designed for heat waves image enhancement.

To optimize the extraction process of total flavonoids from RADIX RHIZOMA GLYCYRRHIZAE and Study on the Antioxidant Activity. Total flavonoids were extracted from RADIX RHIZOMA GLYCYRRHIZAE with ethanol by ultrasonic-assisted method, whose extraction process was optimized by orthogonal test design.The scavenging effect of pumpkin polysaccharide on OH and O2-were studied by salicylic acid and pyrogallic acid method. The optimum extraction process was as follows: ethanol concentration of 75%, solid-liquid ratio of 1:25,ultrasonic power of 350 W and ultrasonic duration of 25 min.Under the above conditions, the extraction rate of total flavonoids reached as high as 1.943%. The influencing order of each factor on extraction rate of polysaccharides was determined to be: ethanol concentration＞solid-liquid ratio＞ultrasonic power＞ultrasonic duration. When the solution concentration is 1.1296mg/ml, the scavenging rate of crude flavonoids on superoxide radical is 50%.Suggesting that it would be an effctive natural free radical scavenger. The study could provide a scientific basis for the further exploitation and utilization of RADIX RHIZOMA GLYCYRRHIZAE

In this paper we propose a novel structure for CRLH-TL,that is symmetrical CRLH-TL structure,used in microstrip leaky-wave(MLWA) ,which will have more advantages than asymmetric structure.because the symmetrical structure allows the unit always in balanced state, microstrip leaky-wave antenna(MLWA)based on symmetrical structure CRLH-TL in balanced state can realize the seamless transition from left hand to right hand , expanding the scope of beam scanning,realizing the beam scanning function of the electromagnetic wave from backward to forward and miniaturization.The phenomenon will be explained theoretically and validated through the measurement and simulation in this paper.

In this article, the prediction model of wheat water requirement was established by optimization algorithm BP neural network, and network topological structure was ascertained. Input-output variable were leafage electricity characteristic and irrigation volume. The BP neural network is trained by 60 sets of experimental data. The result of emulation showed that the BP neural network can solve the uncertainty and non-linear of the model, and the model has high precision.

Energy balance and offgas utilization of ilmenite smelting in 30 MVA direct current electric arc furnace (DC furnace) of a Yunnan company were investigated to make sure safety production, and to save energy and reduce pollution. The total input energy in the DC furnace was 2,000 kWh per ton of ilmenite, in which 1,003.31 kWh per ton of ilmenite was used to carbothermic reduction and other energy was consumed as heatloss. Based on energy conservation, the whole system heatloss in physical production should be controlled at 1,000 kWh per ton of ilmenite. With high combustion heat, the offgas discharged from furnace after treatment could be used to ilmenite drying, anthracite drying, titanium slag drying, and casting ladle baking. The offgas design flow ranged from 5,000 to 8,000 Nm3/h with the mean of 6,500 Nm3/h. The combustion heat quantity of offgas in the plant was 82,160 MJ per hour, which could save 480,276.8 kWh of electrical energy per day, and thus lower carbon emission of the whole production line.

Method of piles thrusted-expanded with column-hammer is a ground treatment method which has Chinese characteristics. In order to study the consolidating mechanism of the ground treatment method, indoor model tests of thrusting hole and tamping pile are carried on and the consolidating mechanism is studied. At the same time, the influence factors of thrusting hole and tamping pile, such as the different tamping energy and diameter of column-hammer, are analyzed. The analysis results indicate that thrusting hole by column-hammer has the effect of lateral compacting and strongly tamping at the bottom of hole. In the tamping piles by column-hammer, the effect of expanding the bottom of pile and secondary compaction are very great. The conclusions will provide the technology basis for the optimizing the design of the ground treatment method.

Diamond-like carbon (DLC) films have being widely applied in various domains owing to their excellent optical and mechanical properties, chemical inertness and bio-compatibility[1,2]. But it generally exhibits low a laser induced damage threshold (LIDT).As to infrared protective films, DLC films were asked to be a high laser damage threshold. So far, the real reason of laser damage is unclear. In order to understand the real reason of the laser damage, it is necessary to deeply research the relationship between optical properties and laser radiation. In this paper, optical properties post irraditing by various laser energy were inverstigated. Hydrogen-free amorphous carbon films were deposited by unbalanced magnetron sputtering with a graphite target on Si substrate in this paper. The DLC films were radiated with raster scans methods by a 1064nm and 8–10 ns laser in this work. The transmittance, refractive index, extinction coefficient and surface morphology of DLC before and after radiation were examined by fourier transform infrared spectrometer, ellipsometer and talysurf respectively. The influences were considered as function of laser energy density.The optical properties before and after laser radiation were compared. It is found that as laser fluences rise from 0 to 0.5 J/cm2, the transmittance peak reduce from 67.06% to 58.27%, the refractive index decrease from 1.88 to 1.67(λ=1200), the extinction coefficient increase from 0.07 to 0.32(λ=1200), and the surface roughness become 149.28nm in this procedλure. Especially, the reasons of change were expounded in this paper.

The structures subjected to large displacement under ground motion may be severely influenced by the structural second-order effects. This paper studied the dynamic second-order effects of the single-degree-of-freedom (SDOF) system under earthquake ground motions. The following achievements have been made: (1) the stiffness reduction coefficients considering and effects under static and dynamic analysis were deduced; (2) through numerical analysis, the accuracy of the formulas was verified.

A 3-layer topology is proposed to solve the problem of the incompatibility of the traditional topology structure in large-scale WSN. The data communication strategy for each level have been analysed, and an topology control algorithm for top-level is brought up based on the bottleneck-nodes, which will provide higher reliability control for the key-level. The experimental results indicated that, the new topology control strategy will contribute to balance the communication load of the nodes, and the energy consumption in the key-level reduce remarkably.

This paper presents a model for automatically generating 3D cartoon ocean water animations in real-time. The dynamic ocean water surface model is modeled by a spectral method. The cartoon rendering process is implemented by multipass on GPU: First, we code normal of ocean model and generate normal map. Next, we extract discontinuities from normal map and smooth it into edge map. Finally we combine the edge map with cartoon shading based on a projective texture mapping. Some experimental results demonstrate the prettiness and efficiency of the presented model.

Opportunistic networks is one of the newest hot research spots in wireless networks after mobile ad hoc net-works(MANET) and wireless sensor networks(WSN). Mobility model describes mobility manners of nodes. It has been widely used in research on wireless network. This paper firstly introduced, classifies, and compares the current familiar mobility models. Secondly, it classifies, and compares the current familiar mobility models. Next, it was discussed that current research focus on new mobility models, analysis of nodes mobility features, trace strategy, and evaluation of mobility model. Finally, this paper involved what calls for further study.

Aiming at the deficiencies of positioning accuracy and matrix operating complexity in the classical MDS-MAP locating algorithm in WSN, a distributed multi-dimensional scaling-MAP algorithm (MDS-MAP (D)) was proposed in this paper. In this algorithm, the distance of the nodes was quantified to obtain the close-neighbor vector (CNV), the distance matrix D and the initial value of nodes location was calculated. Theoretical analysis and simulation experimental results show that, the advance algorithm can realize the positioning of sensor nodes with good accuracy.

We investigate the mechanical properties of Poly Vinyl Chloride (PVC)/ acrylnitrile-butadiene-styrene copolymer (ABS) composite material with an impact testing machine，a material testing machine and other accessory devices. The result shows that the mechanical properties of PVC/ABS composite are a function of composition, the addition of ABS improved the mechanical properties of PVC/ ABS composite，the impact strength and elongation at break rise significantly with increasing ABS content in PVC/ABS composite and appears maximum value，While the tensile strength and modulus almost decrease monotonously with increasing ABS content in PVC/ABS composite.