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Inconel 625 superalloy tubes were hot extruded using a horizontal extruder. Optical microscope, scanning electron microscope (SEM) and energy dispersive spectrometer (EDS) technique were employed to investigate the extrusion defects mainly caused by the primary MC carbides. The results showed that a lot of surface cracks, internal cracks, grooves and shrinkage cavity defects existed in the outer surface and internal of the Inconel 625 superalloy tube after hot extrusion. However, the inner surface of the tube was smooth and no cracks were observed. In addition to the external factors during hot extrusion, the cracks are mainly caused by the primary MC carbides or large dimension of C particles formed due to a relatively short smelting time and large dimension of C particles during smelting with the decreasing plasticity of the grain boundary. This kind of cracks can be avoided through improving the uniformity of the chemical composition by reducing the size of C particles and extending the diffusion time during the smelting of Inconel 625 superalloy.

A Cu-20Ni-20Mn alloy was prepared and the aging characteristic of this alloy was investigated in this paper. The experimental results showed that the strength of solution treated Cu-Ni-Mn alloy was enhanced by more than 500MPa when aged for more than 20h. Much more rapid increase of tensile strength was found in the cold rolling samples during the aging process, and the strength was much higher in the range from 1200-1600MPa. The side peaks found beside (200) X-ray diffraction peaks are believed to be corresponding to the Cu-rich and Mn/Ni-rich phase regions formed by up-hill diffusion. It is also known that this fluctuation of composition is usually described by sinusoidal wave, the wave length of which is estimated to be 10-15nm.

This paper analyzed the content, distribution and source of Cu in Jiaozhou Bay in 1982. Results showed that the Cu contents in surface waters were relatively low, and the pollution level of Cu in 1982 was very slight. The major Cu source in the southwest of the bay was overland runoff; while for the northeast ocean current was responsible. The input contents of overland runoff and ocean current ranged from 2.22-3.56 μg.L-1 and 0.15-5.31μg.L-1, respectively.

Recent years, the image sparse representation has been the popular method in the study of image representation, which has put forward a new idea in the image denoising. Its basic principle is that the original image has the sparse representation under the proper over-complete dictionary. Filter out the noise, we should find out the sparse representation of the image through the design of the dictionary. Its mechanism is that one hand the useful information of the image would be effectively expressed because of the sparse decomposition algorithm based on the redundant dictionary. The other the noise would not be expressed through the dictionary atoms. We do the image denoising according to the image sparse representation. Because of the superiority of the adaptive dictionary algorithm in the image, in this paper, we discuss the over-complete dictionary training algorithm. And we prove the effectiveness through the MATLAB.

Optimal planning of substation locating and sizing is one of the major components of distribution system planning projects. In this paper an approach for optimal locating, sizing and determining the power supply areas of substations using Improved Weighted Voronoi Diagram and Genetic Algorithm (WVD-GA) is presented. For rational power supply areas, variable weights and fixed weights are introduced as new concepts of weighted voronoi diagram to adjust the weights dynamically by considering substation characteristics and load density distribution. And an algorithm based on Cellular Automata (CA) for creating weighted voronoi diagram is designed, which greatly improve the performance of the creating process. The results show the efficiency and capability of the proposed method.

The three components of the color images enhance the images directly in the RGB color space, will cause distortion of the image. So our paper will convert true color image from RGB space to YIQ space, the holomorphic filtering and histogram equalization are executed on Y component to make the image enhancement, the Y component contains a lot of image information; finally, the image is converted from YIQ color space to RGB color space once again. Experimental results show that the approach which were proposed in the paper, Combined with the method of holomorphic filtering and histogram equalization to overcome the uneven illumination, the image is dark and other shortcomings to achieve satisfactory enhancement.

The detection of landmines has become a hard task to deal with because of the diversity of landmines and the complexity of minefield. The development of terahertz technologies has provided a feasible way to detect the buried landmines. Landmines’ shell is usually made of ceramics, plastics, even wood and so on, which terahertz wave could penetrate them easily. The explosives are the major part of landmines. Many types of explosives have the characteristic spectrum in terahertz range, so it would be an effective method to detect landmines by measuring the spectrum of explosives with terahertz time-domain spectroscopy.

In this paper, first we introduce the digital image algorithm of Canny edge detection, and then simulation results of Canny edge detection are given particularly. Test results show that the improved algorithm improves the accuracy of edge detection effectively. Secondly, the algorithm of the region growth, which algorithm is divided into two parts: one is growing region; the other is merging region, is realized. Finally, based on above analysis, we find out that a continuous boundary is not obtained by edge detection, and the method of regional extraction may produce transition segmentation. In response to these deficiencies, we present a region growth algorithm of edge detection.

Fuzzy c-means (FCM) algorithm is an unsupervised clustering algorithm for image segmentation, and has been widely applied because the segmentation results are consistent with human visual characteristics. Enhanced fuzzy c-means clustering (EnFCM) algorithm is the improved FCM algorithm, which reduces the computational complexity. But, both FCM algorithm and EnFCM algorithm, clustering number still need to be manually determined. This paper, in order to realize the automation degree of algorithm, presents an improved algorithm. It first analyzes the histogram, then automatically determines the clustering number and peak value of each class through use of the peak point detection technology, finally segments image by using EnFCM algorithm. Experiments show that this method is a kind of faster fuzzy clustering algorithm with automatic classification ability for image segmentation.

To improve the using efficiency of clean energy, in this investigation, three wind-heating devices, nonlayered-stirring heating device, layered-stirring heating device and layered extruded stirring heating device, were designed, fabricated and tested. The performance of these three devices was investigated experimentally. Results show that, under the experimental conditions, the layered extruded stirring heating device is the most efficient, and its heating efficiency reaches 46.4%. Then, the computational fluid dynamics (CFD) models were established base on these three devices. The comparative analysis of the simulation and experimental results, both obtained consistent heating law. This suggests that the use of the software CFD simulating the stirring heating device is feasible.

A Cu-24 wt % Ag composite alloy is prepared to reveal the evolutions of microstructures, mechanical properties and textures formed by cold rolling. A typical alternating distribution of Cu and Ag phase layers is observed, which becomes much finer with increasing cold rolling reduction. Copper texture ((112) texture) and Goss texture ((110) texture) with high intensities are found in the Cu phase of cold rolled samples. Ag phase containing strong Goss texture and weak Brass texture are observed, quite different from the case in cold rolled pure Ag. Significant change of textures, from the Goss texture to (111) textures with increasing rolling reduction, has been found of Ag phase. The strengthening mechanism of this Cu-Ag composite is described by a equation similar to the HallPetch relationship, the fitted results based on which shows good agreement with the experimental data when the layer thickness is lower than 100-200 nm.

The pure copper tube with strong axial orientation columnar grain and equiaxed grain respectively were rolled using a three-roller precision tube mill. Optical microscope, hardness testing machine and universal testing machine were used to investigate the microstructure and mechanical properties of the pure copper tube rolled with different deformation degrees. The results show that the pure copper tube with two kinds of microstructure can be directly rolled from the dimension of Φ68.5mm×57.9mm to Φ34.7×30.4mm by 8 passes with accumulated deformation degree nearly 80% and without intermediate annealing. With the increasing deformation degree, the primary columnar grain boundaries of the pure copper tube with columnar grain blurred gradually until completely disappeared. However, the microstructures of pure copper tube with equiaxed grain completely transformed into fibrous microstructures when the deformation degree reaches to 79.11%. The columnar grain is without transverse grain boundaries but with small-angle boundary, which is conducive to axial deformation. It is also found that with the increasing deformation degree, the tensile strength of pure copper tube increased steadily, while the elongation decreased gradually. The elongation of pure copper tube with columnar grains is higher and the microhardness is lower than that of equiaxed grains, indicating that the cold deformation properties of pure copper tube with columnar grain was more excellent.

With 4G licenses issued in China, the RRM (Radio Resource Management) conformance test for TD-LTE system becomes a critical work. This paper will use TTCN-3 to achieve the corresponding test case in order to validate the protocol conformance in the measurement process of RRM in TD-LTE system. And it shows the method of implementation and generated GFT. The research work of this paper is supported by national science and technology major special "TD-LTE TTCN extension test set instrument development".

The auxiliary differential equation method has recently been proposed ,It is introduced to construct more new exact solutions for the variable coefficient KdV equations. As a result , hyperbolic function solutions, trigonometric function solutions, and elliptic function solutions rational function solutions with parameters are obtained.

This paper presents a novel topology and the coordinating control strategy of the hybrid cascade energy storage and bi-directional power regulation device. First, the voltage gain and power transmission characteristics of isolated half-bridge DC/DC converter have been analyzed. On this basis, the coordinating control strategy of the two kinds of converters is mainly studied. Finally, a detailed bi-directional power regulation device model is established on a PSCAD/EMTDC platform.

In this paper, from the perspective of network innovative process, we comes up with the basic assumption, that is, the network innovation can promote absorptive capacity of industrial clusters products so as to improve the innovation performance of the enterprises in cluster. On the basis of this, this paper adopts correlation analysis method to verify the influence extent of productive service industry cluster innovation network on innovation performance. Therefore, we find critical influencing factors of network nodes and set up the innovation performance evaluation index system of productive service industry cluster.

The chemical constituents of the essential oil ofThymus monoglicus Ronnin Bashan mount were analyzed by GC-MS. Fifty seven components were identified representing 90.313% of the oil. The main component wasβ-caryophyllene (26.351%), followed by 1,8-cineole (11.888%), sabinene (7.810%),trans-β-Farnesene (6.214%), α-terpinrnyl acetate (4.666%), caryophylleneoxide (3.619%) and terpenene-4-ol (3.543%). Bioactivity screening of this oil sample found it showed a slight activity of anti-bacteria onEscherichia coli,Bacillus SubtilisandStaphylococcus aureus(IC50>500 μg/mL).Introduction

In this paper, by establishing a mathematical model of ship dynamic positioning system, and considering the force and torque of environment disturbance such as wind, wave and flow, a piecewise controller was designed after the study of ship steering motion on three degrees of freedom, in order to improve control accuracy. The model of fuzzy controller and piecewise controller were respectively simulated using MATLAB in x axis direction. The results of simulation show that the piecewise control method improves the dynamic and static performance of the system, and the system acquires a better control performance.

To explore the screw centrifugal pump performance change, and the impact of solid-liquid two-phase flow on the screw centrifugal pump, the internal flow of type 150×100LN-32 centrifugal pump is used as the research object. Mixture multiphase flow model, standard k-ε turbulence model and the sliding mesh technique are used to carry out the unsteady numerical simulation to describe internal flow field in screw centrifugal pump. By Setting the monitoring point to get the pressure pulsation characteristics and predict the changes in the energy performance. Open laboratory bench tests are carried out to verify the reliability of the numerical methods. Based on this, the impact of the two-phase flow on the screw centrifugal pump is analyzed. The results indicate that the head-flow curve presents a hump-shaped with the increasing of the flow. The maximum of efficiency appears. At the same time, the change of the volume concentration of the solid phase has little effect on the energy performance of screw centrifugal pump. But at different times, the head decreases and the power increases with the increasing of the concentration.

Grinding experiments were conducted using vitrified CBN wheel on particulate reinforced titanium-based matrix composites (PTMCs) and Ti-6Al-4V matrix. The issues discussed are grinding forces, surface roughness, and the formation of surface integrity. The main results are summarized as follows: (1) The grinding forces increase with the increasing workpiece speed and depth of cut during grinding PTMCs and Ti-6Al-4V materials. (2) Decreasing depth of cut properly contribute to obtaining finished surface with good surface during grinding of PTMCs using CBN wheel, but the workpiece speed has little influence on the surface roughness value of PTMCs. (3) The formation of surface integrity of PTMCs is due to the combined removal of the TiC and TiB reinforcements and the Ti-6Al-4V matrix.

Grape-like structure La3+-doped ZnO nanofibers with different doping concentrations were prepared by electrospinning-calcination technology. The resultant nanofibers were characterized by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), photoluminescence spectrum (PL) and X-ray photoelectron spectrum (XPS) respectively. The photocatalytic activities of the nanofibers for the degradation of Rhodamine B (RhB) in aqueous solution were studied. Results show that the doping concentration of La3+ has an significant influence on the photocatalytic performance of the nanofibers, and 2 mol.% La3+ is the optimal doping concentration.

The present article deals with the surface topography during high speed grinding of particulate reinforced titanium matrix composites (PTMCs). Scanning electron microscopic images of the ground surface was analyzed. Combining the results presented in this paper, the following results could be summarized: (1) The reinforcing particles of PTMCs are removed by means of voids, pulled-out, fracture or crushed, and micro-cracks, which attributed to the plowing and shearing during high speed grinding. (2) The formation of the fracture pattern of PTMCs is formed due to the wear debris of the abrasion during high speed grinding.

industrial Control System (ICS) performs the tasks of supervisory control and data acquisition of critical infrastructures. With the widely application of computer and network techniques, ICS suffers serious security threats, and malicious codes are one of the most serious security problems. However, there is absent of analysis methods specific for ICS malicious code behaviors in current times. In this paper, a framework for ICS malicious code analysis is presented. Firstly, the ICS attack graph model is established based upon the hierarchical structure of industrial control system and the suffered security threats, which formalizes the attack process of ICS malicious code. Secondly, the runtime information of ICS malicious code is detected and collected for analyzing and assessing the attack behaviors and the resulted impacts. Finally, the ICS simulation environment for malicious code analysis is constructed based upon the framework and the experimental analysis of ICS malicious code is performed which preliminary validates the effectiveness of the proposed framework.

This article studies the effect of process parameters on the grindability of Ti-6Al-4V and particulate reinforced titanium matrix composites (PTMCs) comparatively, using the wheels of white alundum (WA) and cubic boron nitride (CBN) respectively. The processing variables, such as grinding force, grinding temperature, specific energy were investigated in detail. The results indicate that the grinding force and temperature with WA wheels were obviously larger than that of CBN wheels. The specific energy of Ti-6Al-4V and PTMCs decreased gradually with the increase in the maximum underformed chip thickness using the two different wheels.

Particulate reinforced titanium matrix composites (PTMCs) are attracting increasingly attention in various engineering applications. In this paper, comparative grinding experiments of PTMCs were carried out using WA abrasive wheel and CBN abrasive wheel. The morphology of the ground surface was observed by scanning electron microscope. The main results are summarized as follows: (1) The damage of reinforcements in the PTMCs results from the plowing and shearing during grinding in the form of crater, micron gap, broken, coating and micron crack. (2) The formation of grinding chip is a function of the collaborate removal of reinforcements and matrix material. (3) The surface fracture pattern of PTMCs using WA wheel is to form the grinding chip through severe extrusion. While using CBN wheel, the abrasion due to the formation of the wear debris is the main surface fracture pattern of PTMCs.

Chinese traditional favonian patterns as a kind of language and symbol, has been widely applied in the design of silk home-textile, on the basis of description of Chinese traditional favonian patterns, then from three aspects, which are the extension of meaning,the adornment of the form,the combination of pattern and color, to focus on the creative applications of the Chinese traditional favonian patterns on silk home-textile design, to help the design of silk home-textile product.

In the TD-LTE system, RRC (Radio Resource Control) layer plays a very important role as the control center in the whole higher layer protocol. This paper introduces the function of RRC layer and mainly focuses on the RRC layer connection reconfiguration. This paper also illustrates design of function, signaling process and uses the third party terminal and tracking software to calculate the corresponding diagram in the domain of log, which checks the implementation of RRC layer connection and reconfiguration.

Effects of the technological parameters (superheat, cycle times and holding time) on undercooling and structure of Ag-28.1 wt.% Cu eutectic alloy were discussed by orthogonal experiment. It shows that the influence of the superheat on undercooling is biggest, followed by cycle times, and finally holding time. Then the optimum process parameters of getting different undercooling are given in this paper. In the Ag-28.1 wt.% Cu eutectic alloy melt, cellular growth of lamellar eutectics takes place because of the large difference in composition between the two eutectic phases and the very large thermal diffusion coefficient of the liquid, and when undercooling is equal to or higher than 76 K, lamellar eutectics grow in a dendritic form during rapid solidification.

GIS is now widely applied in power systems. It might lead to severe consequence when accidents take place, so online monitoring on GIS systems is necessary. Based on function analysis of the needs of GIS intelligent condition monitoring, a modeling method, a communication system and data exchanging interfaces, meeting IEC 61850 intrinsic ideas, are presented. Sharing and interacting strategies for intelligently-monitored GIS condition information are discussed. Focusing on MMS-based server/client communication mode, some information exchanging principles based on MMS messaging, logs and files are clarified. Server-client information exchanging communication programs are designed, and the flow charts of essential functions and client/server are also presented.

This paper mainly deals with the reconstruction and fractal analysis of wear topography of brazed polycrystalline cubic boron nitride (PcBN) grain in grinding process. On the basis of fractal analysis, the uncertainty in shape and complexity in wear mechanism are analyzed by means of the construction of micro fracture of PcBN grain after producing the brazed abrasive tool with PcBN grains and carrying out grinding test. The main results are summarized as follows: (1) Actual behavior of self-sharpening phenomenon due to micro fracture in the grinding process can be grasped and reconstructed using SEM and 3D video microscope. The reconstruction model can clearly express the complicated wear features and characteristics of the grain. (2) The fractal dimension can relate the performance of PcBN grain to its micro fracture, and then the self-sharpening phenomenon due to micro fracture can be evaluated quantitatively on the basis of fractal analysis.

How to design the interfacial properties is a significant fundamental issue in the field of the composite materials, while little work was concerned with the mechanical design of the interface for the fiber reinforced polymer. In the present work, a fiber bundle embedded in the matrix was described as a transversely isotropic material. Based on the imperfect interface conditions, the interface parameters were derived to satisfy the neutral conditions for the composite materials reinforced by the elliptical cross-section fiber bundle. It is found that the interface parameter is not always associated with the applied loading in the case of the anti-plane shear. In the state of equal-biaxial tension, the normal interface parameter is merely related to the mechanical properties of components except for the shape of the fiber bundle, but independent of the loading magnitude. In the other cases of pure shear and uniaxial tension, the neutral interface does not exist except that the fiber bundle has a circular cross-section. It is also found that the interface parameters can be expressed in the forms similar to that for an isotropic inclusion by using Kolosov constant in the in-plane deformations.

Based on the theories of fuzzy set and fuzzy conversion, the method of fuzzy comprehensive appraisal is a decision-making process which combines qualitative analysis and quantitative analysis and can be used to forecast risk of electric power engineering projects. Using the method of AHP to establish risk early-warning indicators system and method of fuzzy comprehensive appraisal to establish risk early-warning model, the paper constitutes risk early-warning system of electric power engineering projects. A case from western China is applied to prove the validity of the risk early-warning system.

InP/In0.82Ga0.18As/InP heterostructure used for infrared detector were grown on (100) S-doped InP substrates using two-step growth technique by low temperature metal-organic chemical vapor deposition. The growth was performed using TMIn, TMGa, AsH3, and PH3 as growth precursors in a horizontal reactor. The substrates on a graphite susceptor were heated by inductively coupling RF power, their temperatures were detected by a thermocouple, and the reactor pressure was kept at 10000 Pa. The growth structure of detector included In0.82Ga0.18As buffer with the thickness of 100 nm, In0.82Ga0.18As absorption layer with the thickness of 2.8 μm, and the InP cap with the thickness of 0.8 μm. The planar type of p-i-n detector was fabricated by Zn diffusion. The properties of In0.82Ga0.18As detector were studied, the curves of the I-V characteristics, the range of response spectrum, and the detectivity (D*) were obtained.

Based on the principle of virtual prototype reality design and combined with the desired improvement of the user individuation in current product development. The system structure model of virtual prototype reality design of numerical control machine for Users is proposed. The main contents of the virtual prototype reality design system support environment in this model are discussed. The key technique of design process realization is provided.

In this paper, we introduce the squeeze casting process to produce flange. This article also introduces the optimized roughcast of flange, the cruces of the die design, the main structure parameters and the working traits of the die. The result shows that using squeeze casting method to produce flange not only can get the qualified part, which also greatly increase the material utilization together with enormously save processing time and processing costs at the same time.

Flow behavior and microstructures of GH625 superalloy were investigated by hot compression tests. Then the GH625 superalloy tube was hot extruded according to the hot deformation behavior, and the microstructures of different position of extruded tube was also analyzed. The results show that the actual deformation temperature of the specimen deformed at a strain rate of 10.0s-1 is higher than the preset temperature, resulting in a deformation thermal effect. Thus, the microstructure evolution of GH625 superalloy is controlled both by the strain rate and deformation temperature. It is also found that the GH625 superalloy tube can be successfully fabricated with a stable extrusion speed of 40 mm·s-1, extrusion ratio of 4.1 and preheating temperature of 1200°C. The microstructure of extruded tube was obviously fined due to the occurrence of dynamic recrystallization(DRX). Different degrees of DRX were observed in outer wall, center and inner wall of the tube, which is similar to that in the head, middle and tail of the tube. An extruded tube containing fully DRX grains can be obtained by cutting the head and tail of the tube, and machining a small amount of the inner wall.

Dye-sensitized solar cell(DSC) is a new type of photovoltaic device. This paper mainly describes the research results of the development of a novel nitrogen-doped photoanode for DSC in our group. Highly efficient dye-sensitized solar cells (DSCs) of 7.6-10.1% were fabricated using nitrogen-doped titania electrodes. The photoelectrochemical properties of the nitrogen-doped titania powder, film, and solar cell were systemically investigated. We confirmed the substitution of oxygen sites and oxygen deficiency with nitrogen atoms in the titania structure by X-ray photoemission spectroscopy (XPS). The UV-Vis spectra of the nitrogen-doped powder and film showed visible light absorption in the wavelength range between 400 nm and 535 nm. The results of the stability test indicated that the DSCs fabricated by the nitrogen-doped titania exhibited great stability.

Microstructure evolution during dynamic recrystallization (DRX) of hot deformed GH625 superalloy was investigated by optical microscope (OP) and transmission electron microscope (TEM). Hot compression tests were conducted using Gleeble-1500 simulator. It was found that the nucleation mechanism of DRX for the alloy deformed at 1150°C is composed of discontinuous dynamic recrystallization (DDRX) and continuous dynamic recrystallization (CDRX) in the vicinity of the serrated grain boundaries. With the increasing strain, the fraction of the DRX grains increases, while the size of the DRX grains almost remains in the same range. As the deformation temperature increasing, the size and fraction of the DRX grains increase, and no precipitation of intergranular carbides are found when the deformation temperature increases to 1150°C. At lower strain rate, the size and volume fraction of DRX grains decrease with the increasing strain rates. However, the size and volume fraction of DRX grains increase at higher strain rates due to the deformation thermal effect.

This paper describes a study on damage identification using wavelet packet analysis and neural networks. The identification procedure could be divided into three steps. First, structure responses are decomposed into wavelet packet components. Then, the component energies are used to define damage feature and to train neural network models. Finally, in combination with the feature of the damaged structure response, the trained models are employed to determine the occurrence, the location and the qualification of the damage. The emphasis of this study is put on multi-damage case. Relevant issues are studied in detail especially the selection of training samples for multi-damage identification oriented neural network training. A frame model is utilized in the simulation cases to study the sampling techniques and the multi-damage identification. Uniform design is determined to be the most suitable sampling technique through simulation results. Identifications of multi-damage cases of the frame including different levels of damage at various locations are investigated. The results show that damages are successfully identified in all cases.

In this paper, based on the liquid forging part flange LY12, the influence of heat treatment on the organization and performance of the liquid forging part was studied through microstructure, mechanical properties and tensile fracture surface analysis methods, this article also has some guiding significance to the formulation of the best liquid forging process parameters. The results show that the sample after natural aging which mechanics performance is best, and grain is relatively small; the latter two that after artificial aging are relatively poor. With the extension of artificial aging time, the mechanical properties and the organization has a descending trend.