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For the purpose of expanding the application scope of HEA coating manufactured on the surface modification of materials, in this work, the Al1.5CrFeNiTi0.5 and Al1.5CrFeNiTi0.5W0.5 HEA coatings were successfully manufactured using laser cladding method on SUS304. The microstructures and wear resistance of coatings are researched systematically. It is found that the W0 and W0.5 HEA coatings all exhibit the dendritic structure, which are constituted by BCC phases and Laves phases. With W element addition, the phase structures of W0.5 coating remain unchanged. W is dissolved in both two phases, but the solid solubility in Laves phase is higher compared to that in BCC phase. W0.5 coating with the highest microhardness of 848.34 HV, and the W0 coating with the microhardness of 811.45 HV, both of whose microhardness are four times more than that of SUS304 substrate. Among all samples, the W0.5 coating shows the optimal wear performance because of its larger content of hard second phase ( Laves phase).

In order to improve the authenticity of human-computer interaction in the virtual scene, the data glove is used. Aimed at this sensor input device for the characteristic of multiple-joints, the collection and calibration method of original data are discussed. By analyzing the movement characteristics of human hand, mapping from human hand to virtual hand is accomplished. By embedding OSG in MFC, with the intersect vector method and map projection method, invoking the 3D ship engine room and interactive effect of people roaming in the scene are reached. And at last, by using the data glove, the interventional manipulation of virtual objects in the virtual scene is implemented.

Ship maneuvering model and ocean scene are the core parts of navigation simulator, on the basis of MMGs model, the dual-engine and dual-propelling equipment of the Z-propeller tug were researched, the tugs mechanical model and propulsion model were established, speed, course and path of the tug were calculated with the Runge-Kutta method; virtual ocean was built at the meantime based on waves statistic spectrum and fast fourier transform; at last, data communication between different softwares was realized by means of UDP and ADO protocol, and virtual marine navigation system was established based on the Z-propeller tugs maneuvering model.

in order to monitoring connecting rod and crank pin bearings working condition, the PCOT monitoring system which was named crank pin oil temperature monitoring system was developed based on virtual instrument technology. The bearings working condition was estimated by testing oils temperature splashed from the connecting rod and crankshaft. The function, working principle and structure composition were described, and corresponding experimental prototype was researched. After experimental verification, this system could monitoring the crank pin oil temperature in a steady and reliable state, provided technical support for testing bearings faults.

This paper established the mathematical model of Logistics distribution routing problem,and departed the multiple vehicle routing problem into a single vehicle distribution problem with the save mileage method ,then the ant colony algorithm were used to optimize the single vehicle distribution problem. Finally through a case shows that the model for the practical application of logistics distribution has certain reference significance.

This paper introduces a minor drainage pump used in air-conditioning system. The numerical simulation has been done to analyze the internal flow field and sound pressure level in drainage pump. FlUENT is used in this paper. And LES (Large Eddy Simulation) is taken to catch the pressure fluctuation in this flow passage. CFD results show that pressure fluctuation is the main sound source in the pump.

The Qionglai stone archway and stone screen wall are located in Tiantai Mountain, Sichuan Province. Due to the impact of the 5.12 Wenchuan earthquakes, the stone archway began to subside and tilt. The maximum settlement of the two columns in the northeast was 60mm and the vertical deviation was 42mm.The main ridge of the roof which was badly damaged was out of joint and began to fracture, shift and fragment. Other part also got damaged in varying degrees. Due to the special geographical environment, large-scale machinery cannot be put into use. Thus, we can only use small equipment and labor, take advantage of pulley block and set up a steel hoop to improve pillars with jacking and corrective method. At the time of repairment, it should follow the principle of "repair the old as not to change the original appearance" and use the original materials and follow the original process as much as possible so that the stone archway and stone screen wall can be in the original shape.

This paper establishes an enterprise information system configuration management model based on graph theory. Comb all nodes support enterprise information systems for the application system, host, operating system, middleware, database, applications, a database instance, network devices, storage devices, virtual host, virtual platform,11 kinds of configuration items. And sort out the relationships between them to no effect, no effect of virtual relationship, positive impact, positive impact of virtual relationships, reverse impact, reverse impact of virtual relations,6 kinds of relationships. All configurations supporting enterprise information systems and the relationships of them is seen as a weighted digraph. Then the weighted digraph is represented as an edge weight matrix. The edge weight matrix of a particular application system configuration relationships graph is solved according to the edge weight matrix of global configuration relationships graph, Help Operations staff clearly identify the composition of the information systems. The edge weight matrix of the impact of a change on a configuration item is solved according to the edge weight matrix of global configuration relationships graph. Provides a valuable reference views to operations staff when they repair a configuration.

A power plant in Hebei province aimed to use sodium hypochlorite as fungicide for the circulating water in its seawater electrolysis system by recycling desalination brine. The feasibility of this process was intensively studied using water quality analysis, electrochemical corrosion tests, and dynamic simulation tests. The results showed that this process is more efficient than that using seawater and would not aggravate the corrosion problem that is present in the current system. Scale produced by the electrolysis can be completely removed by acid-washing.

An improvement of coterminous frames differencing is proposed. By using the improved algorithm, the snow point from video image obtained in the snow day can be removed significantly. The snow regions are extracted by the temporal difference of pixels from the five adjacent frames in video images, The absolute value of differential luminance of each frame is then obtained. The luminous intensity of the background and effects by snow can be further computed. Finally, the intensity of the contaminated pixels is replaced by the average value of future and past frames. The results of the experiment show that this algorithm can improve the quality of video images in light snow, heavy snow even heavy snowstorm strongly.

Because various lithologic rock present very obvious differences in many aspects (such as: the apparent lumpiness, longitudinal wave velocity, mechanical property etc), the results of the rock mass structure classification by using current specification or general methods can not reflect the true engineering geological properties. Based on a large number of onsite structural surface investigations, acoustic measurements and field and laboratory tests, this paper discusses the related issues on division of rock mass structure using single lumpiness indicators and analyzes the impact of the structural body property and structural surface effect on the rock mass structure. At the same time, the related issue on the integrality coefficient is discussed in the evaluation of rock mass integrity degree. Finally, the proposal which rock structure classification should consider the structure bodys strength and stiffness, the structure surfaces extension length and closed degree, the structure body block size and the rock mass compression wave velocity is put forward.

This paper introduces a new mixing equipment. The numerical simulation and experiment have been done on the internal flow field and mixing effect of the new mixer and for a conventional Kenics static mixer. The exit mixing uniformity is used as an indicator to evaluate the two mixers’ mixing effect. For the adjustable mixer, when the blades angle increases, the mixing uniformity increases. But when absolute value of the angle passed 30°, the rate of increasing begins to slow down. For avoiding too much flow resistance in high workload, the new mixer’s blades rotating angle should be within ±30°. The production of high strength large scale shear eddies on the wake behind the swirl blades in the adjustable mixer is the key for the effective mixing of flocculant and raw water. According to the numerical simulation and industrial experiments, the new adjustable mixer not only can adjust blade angle to fit different working conditions, but also can quickly mix the raw water with flocculant in the pipe behind the blades. The new mixer’s mixing speed and mixing effect are both obviously better than the conventional Kenics static mixer.

This paper presents a new type of adjustable mixing equipment, and the internal flow field of the adjustable mixer have been studied by using the model of LES(Large eddy simulation),and the pressure loss, the speed change and vortex scale have been studied. In conclusion, along with blades angle and number increases, the flow resistance increases violently, so the range of blade rotating angle should be controlled within 30 degrees. As the depth of the pipeline velocity is increasingly large, large velocity gradient is contributed to the collisions between the colloidal particles. In pre-mixed, the vortex effect of the pipeline highly enhances the vortex diffusion, and improves the mixing efficiency. The vortex strength will be reinforced and dimension will be reduced, with the vanes cutting the flow, which can help flocculation.

Braking trace is the important basis to reconstruct the speed of the accident vehicle. There does not exist one-to-one relationship between the barking trace and the vehicle speed. It needs to have a further research on the factors influencing their corresponding relations, otherwise it may appear great errors to reproduce the vehicle speed with the braking trace. This paper analyzes the influence of people, cars, roads, environmental factors on the corresponding relationship between the initial braking velocity and braking traces, explores the use conditions and parameters selection of the reconstructed model in the standard GA/T643-2006, and the experiment is designed to research on the uncertainty of the reconstruction of the model. Besides, it has proposed the experimental reconstruction method.

After the traffic accident, it needs to confirm the cause and responsibility of the accident, and whether the bad brake performance is the important reason for the accident. At first, this paper has put forward the road test standard of the brake performance and comprehensively analyzed the braking process. Except the theoretical analysis, this paper has made a quantitative research on the influence of people, vehicles, road, environment and testing instrument on the brake result of the road test with the experiments and put forward some suggestions to reduce the influence of the test results.

Based on the research of formation lithology, geological structure, deformation failure mechanism ,rock-mass quality and mechanics parameters of the diversion tunnel inlet slope at the right bank of Jinchuan Hydropower Station, a numerical three-dimensional geological model of slope and structural surface was established by applying 3D modeling program, and combined with the slope excavation design, cuttings of transverse and axial direction are conducted, thus, the structural surface location and the rock-block combination are obtained in the excavation face and excavation process. And then, the stability of deterministic block body is calculated by using commercial rock-slope stability-calculation program. By using the probability analysis method in analysis of dominant structure plane combination, possible random combination block of the rock can be get, and then, the block stability calculation is carried out. The results show that deterministic blocks and random combination blocks have good stability under all kinds of working conditions.

The directionally solidified Nb-Ti-Si-Cr-Al-Ta-Hf-C-B (NTS-09C) superalloys were prepared by HRS method. This alloy with strong orientations of (Nb, Ti)ss and Nb-silicide along the growth direction consists of (Nb,Ti)ss, (Nb,Ti)3Si, Nb5Si3, MC carbide and C14 Laves phases. Not only the morphologies and compositions of various phases have been systemically studied, but also the formation mechanisms have been analyzed and discussed in detail.

Great achievements have been made in rock mass structure research to evaluate engineering properties of rock mass in the engineering geology field. In fact, rock mass structure can not only indicate the quantity of structural planes (discontinuities) and size of rock blocks, but also indicate the integrity and mechanical properties of the rock mass. More and more attention has been paid to rock mass quality classification by using rock mass structure. During the past 40 years, rock mass structure research has been carried out by many scholars, and various standards of rock mass structure classification have been proposed in different industries of different countries. In these standards, the most widely used index was the spacing of structural plane. However, it is a pity that the method of determining the spacing value is not unified in different standards, therefore, the structure type of a rock mass may be different according to different standard. But which kind of method to determine the spacing value is most reasonable? It becomes an important problem to be solved. In this paper, rational method of determining the spacing of structural planes is demonstrated based on lots of statistical data in dam abutment rock mass of one large-scale hydroelectric project in Southwest China.

Earthwork excavation, as the primary work of the project, the calculation method in quantity not only affects the project budget, but also has a significant impact in the overall project design and construction schedule. This paper applies Kriging algorithm, in combination with 3D modeling, to build accurate 3D solid model through close space, and uses graphic element Boolean operations to create accurate calculation method in quantity of Earthwork in complex engineering, which can display the data of quantity of Earthwork respectively as well as the space, achieve visual design of Earthwork to make up for the deficiency of traditional method, provide accurate calculation for organizing excavation engineering and visual decision-making information.

In the process of evaluating the stability of some rock slopes, the discontinuities which mainly destroy the stability of future slope can not be understood and the locations of the slope can not be determined because of lacking of the exploration data. This paper determines the combination molds and the location of potential sliding surfaces using the method of crack network simulation to do statistics about all the discontinuities, which aims to resolving the problems of determining the locations and idiographic conformations of potential sliding surfaces in the rock slope.

Mechanical properties of sand-pebble layer is very unstable, it is unfavourable for TBM excavation. For the reasons of poor soil conditioning and low plastic flow of muck, EPB TBM tunnel construction in sand-pebble layer of Beijing metro has exposed variety of issues: continuous dynamic earth pressure balance is hard to established, mud cake is formed frequently in earth chamber, key construction parameters such as thrust, torque, advance speed can not be controlled in reasonable scopes, which lead to low efficiency of TBM construction. Taking“Xi-Liu”of line 10 lot 11 as an research object, the mechanical characteristics of sand-pebble layer and construction problems of TBM advancing are analyzed, variety of soil conditioning measures are used for improving plastic flow of muck and minimizing construction influence induced by poor geological conditions, meanwhile contrast studies on key construction parameters before and after soil conditioning are carried out. The results indicate that effect of soil condition plays very significant roles in controlling TBM construction parameters and improving advancing efficiency.

Tensile behaviors of extruded and rolled AZ80 Mg alloy were investigated with elongation-to-failure tensile tests at constant temperatures of 300 °C, 350 °C, 400 °C, and 450 °C, and constant strain rates of 10-2s-1and 10-3s-1. Experimental data show that the material exhibits tensile ductilities of over 100% at 400 °C and 450 °C, featured by long steady state deformation. Microstructure studies show that annealed coarse grains were remained in the gauge region during the tensile tests, and the enhanced tensile ductilities resulted from dislocation creep, other than dynamic recrystallization or grain boundary sliding. Cavity evolution and recrystallized coarse grains near fracture end caused premature failure of the material.

By means of melt blending process in a co-rotating twin screw extruder with two-step process, the low density polyethylene (LDPE)/ethylene octene copolymer (POE)/zeolite molecular sieves (ZMS) composites were prepared. The influence of ZMS on the crystallinity, mechanical properties and permeability was investigated by differential scanning calorimetry(DSC), universal testing machine and permeability tester, respectively. The results showed that the addition of ZMS made the crystallinity of composite film decreased and the growth rate of crystal nucleus promoted. As the content of ZMS rose, the mechanical properties of composite film decreased, while the CO2, O2permeability and the moisture permeability increased.

Digitized hypoid gear’s surface model, which is constructed by NURBS method, can set free the constraints of conventional processing technique in the process of designing and manufacturing hypoid gear. The digitalization of tooth surfaces of hypoid gears consists of three parts: building large gear’s NURBS model, calculating small tooth surface’s character parameters based on actual requirements and small tooth surface’s digitalization. The digitalization of tooth surfaces can be realized by machining simulation, and the key points are how to establish equations of cutter head and grids of gear solid, and how to judge correct trace points in the process of machining simulation. With the aid of digitized model of hypoid gear, tooth contact analysis can be accomplished by regular motion of two NURBS tooth surfaces.

Reverse engineering, which is an approach for constructing a CAD model from a material solid through dimensional measurement and surface modeling, could be used to structure digitized tooth surfaces of hypoid gear. The reverse engineering of a NURBS tooth surface can be considered as specific number of curve's reverse solution, and the key is the structure of control equations and the selection of boundary conditions in each of reverse processes. According to NURBS theory, the coordinate, normal vector and various kinds of curvatures of all of points in the tooth surface can be solved. Thereupon, the engagement analysis of gear pairs can be achieved before manufacturing, and it is possible to amend manufacturing parameters in time so as to obtain tooth surfaces which meet the needs of function.

By mixing PEG or LiCl respectively into the casting solution, the polyurethane (PU)/SiO2 hybrid membranes were prepared by means of immerged phase inversion process. The method of NMR relaxation time T1 value was used to determine effect of the segmental movement of PU macromolecule in the casting solution on the microporous structure of membrane. The membrane section photos of SEM and properties of the PU hybrid membranes were investigated respectively. The results showed that blending SiO2, and with LiCl or PEG into the PU solution system, the T1 value synchronistically decreased. That was relaxed of PU chain winding and ease to move. The additives of PEG could influence the casting solution of PU, it enhanced the distribution of SiO2 in the casting solution, and formed fine interfacial micropores, meanwhile the retention of the membranes were increased to certain degree whereas the pure water flux could kept at a higher level. Similarly, adding some quantity of LiCl could obtain the membrane with higher retention under the condition of slightly loss of pure water flux. Even thought that there were equivalent quantities of finger pores in section of membrane, mixing PEG or LiCl in the casting solution, the SEM section photos indicated that there were more micropores in the wall of pore.

Multimedia-based teaching and learning is an interesting, interactive, innovative and individualized teaching-learning mode. But according to our survey, there are often some problems in multimedia teaching and learning in practice, such as: lack of emotional exchange between students and teachers, insufficiency of student’s independent learning ability, students’ dilemma in what to choose to learn from diverse online contents, unexpected technical failures, etc. All these factors affect the effectiveness of multimedia teaching. Teachers and students who involve in the multimedia-based English teaching-learning should pay full attention to the problems above, so as to take full advantage of the multimedia technology to improve the effectiveness of the multimedia teaching and learning.