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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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.