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A series of polyethylene terephthalate (PET) hybrid materials with high-load TiO2 content were prepared via in situ polymerization by dispersing unmodified titanium dioxide (TiO2) in Ethylene Glycol (EG), and the influence of load TiO2 nanofillers on the physical properties of PET masterbatch was investigated. The intrinsic viscosities of the prepared PET hybrid materials were affected by the addition of the nanoparticles and in both cases a slight decrease was observed. In addition, the thermal behavior of these PET hybrid materials and neat PET was investigated using Differential Scanning Calorimetry (DSC). The chemical structures of PET hybrid materials were characterized by Fourier Transform Infrared (FTIR) and Scanning Electron Microscopy (SEM). The TiO2 nanoparticles show well dispersibility in PET matrix. The PET hybrid material with 40wt.% TiO2 content was used as master batch to prepare full dull PET fiber with 2.5 wt.% TiO2. The melt flow ability of PET hybrid materials shows good winding and drawing performance, and also the resulted fiber has better mechanical properties than neat PET fiber. It suggests that this PET/TiO2 masterbatch by in situ polymerization may find good application for delustered fiber preparation.

The crystal structure of GdFeMn alloy has been investigated by using X-ray powder diffraction (XRD) followed by Rietveld refinement technique, differential thermal analysis (DTA) and scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS) techniques. XRD results showed that annealed GdFeMn alloy was a single phase of Gd6(Fe0.5Mn0.5)23 compound, with Th6Mn23-structure. SEM/EDS results and Rietveld refinement revealed that GdFeMn alloy was not really a new ternary compound as reported, but a solid solution Gd6(Fe0.5Mn0.5)23 which was only a point between Gd6Fe23 and Gd6Mn23. It was also found from DTA measurement that a reaction, Gd (Fe0.5Mn0.5)2 → liquid (rich Gd) + Gd6(Fe0.5Mn0.5)23, had taken place above 650.81 oC, and the educed Gd existed in educed part of GdFeMn sample. The results demonstrated the real structure of the GdFeMn compound as reported was Gd6(Fe0.5Mn0.5)23 compound.

Ultrasonic peening forming (UPF) is a newly developed sheet metal forming technology which has been applied in the aerospace engineering. It has the advantages of low equipment cost, portability, no pollution and excellent comprehensive performance of the material after being formed. It will have a broad application in local forming and sizing of airplane wing panel. When the panel is relatively thinner, there will be two different types of instability in the panel surface after being formed, one is a local instability, and the other is a global instability. As to the local instability, an equal ratio partial structure of the wing panel was chose as the experiment research subject, which has the same thickness and local area dimension. The simulation of the ABAQUS software showed the variation of arc height for different thickness panel under different impact amplitude, the results showed that arc height changed negatively when the impact amplitude reached a specified value, namely global instability. When the thickness is up to 3.2mm, the arc height of panel increased linearly implied the global instability stopped. As to the local instability (spherical bulge phenomenon), a partial component with the same proportion substituted for typical complex flat panel. Control variable method is used to study the spherical bulge deformation in local panel region, the relationship between shot peening time and impact amplitude was established. The result showed that he larger impact amplitude, the smaller the impact time was when the local instability occurs. The research results have great guiding significance over the practical manufacturing process.

Duck wave energy converter has the advantages of high conversion efficiency, simple construction, low cost relative to other wave power device. In the paper, the numerical simulation of the response of the converter was calculated by the AQWA software which based on the three dimensional potential flow theories. The results show that the pitch angle appear the peak when the incident wave frequency is 1rad/s and the maximum of the pitch angle come out as the linear wave normally incident the duck body, which means duck wave energy converter can absorb more wave energy in this angular frequency. The above research can provide reference for the design of the duck wave energy converter.

Mn100-xFex (x=50, 58) alloys were prepared by spark plasma sintering (SPS), and the structure, magnetostriction and magnetic properties of the polycrystalline Mn100-xFex alloys were investigated. The results of XRD and SEM showed that the as-cast and annealed samples presented a single face center cubic γ-phase, which is austenite structure. The magnetic measurement showed that Mn100-xFex (x=50, 58) alloys annealed at 700oC were a typical ferromagnet at low temperature and there was a gradual transition from the ferromagnetic phase to the paramagnetic phase in a wide temperature region (about 150-250K). The magnetostriction for the annealed samples, measured by strain-gauge bridge up to 3T, was ~100 ppm at 300K, but the results was chaotic. The results are not in agreement with the results reported. The further research on the mechanism of the magnetostriction is needed.

The single-phase Mn1.2Co0.8Si0.2P0.8 compound was fabricated by the spark plasma sintering (SPS) technology followed by vacuum annealing. The microstructure, Néel temperature (TN) and “inverse” magnetocaloric effect of this compound were investigated. The results show that the structure of Mn1.2Co0.8Si0.2P0.8 compound prepared by SPS is a single phase with precise stoichiometric proportion. Increasing the magnetic field from 0.05 T to 1 T, the TN of the material reduces gradually from 110 k to 45 k, and a splitting of TN appears. The splitting of the antiferro-to-ferromagnetic transition is an intrinsic feature rather than the secondary phase. Though the maxima entropy changes is about 0.6 Jkg-1K-1 at B=5T, the Mn1.2Co0.8Si0.2P0.8 phase synthesized by SPS is more favorable, more overall magnetic moment. In addition to the magnetic refrigeration applications, this compound may be used in thermomagnetic generators.

The new all-terrain mobile platform can improve the human mobility in non-structure environment, which is mainly determined by the walking mechanism quality. In this paper, the walking mechanism structure is designed, and its working principle is analyzed. Theoretical analysis and parameter optimization are completed during the parameter design of the tracked circle, which verifies the parameter rationality of the self-tension mechanism. Besides, the dynamic analysis of the multi-degree of freedom suspension system is accomplished. The results show that the structure and parameter design of the walking mechanism is available, which provides theoretical basis for the new mobile platform parametric design.

The hole in the shale formation is in nanometer or micrometer scale, so the conventional plugging materials which are in the scale of millimeter cannot be used during the drilling of the shale formation. An effective way to solve this problem is to develop new plugging materials, which are in the nanometer or micrometer scale. In this article, the micron copolymer particles were prepared by the soap-free emulsion polymerization of the monomers methyl methacrylate (MMA) and acrylamide (AM). The structure of the copolymer particles was characterized by the Fourier transform infrared spectroscope (FT-IR). The particle size was determined by dynamic light scattering (DLS). In addition, the salt tolerance, temperature resistance and compatible property of the particles with the additives of drilling fluids were studied in detail.

(Bi1-xSmx)(Fe0.95Mn0.05)O3(x=0.00, 0.03 and 0.06) thin films were deposited on the quartz substrates by sol-gel technique. The results of X-ray diffraction patterns indicated all thin films had rhombohedral perovskite structure. Moreover, the Sm and Mn co-doping at A-and B-site of BiFeO3resulted in the structural distortion. Scanning electron microscope measurements exhibited that the uniform surface morphology could be obtained by co-doping and the average grain size of the films decreased with increasing Sm content. Furthermore, the fundamental absorption edges ofxBSFMO films showed a blue shift with the increase of Sm content which can be observed in transmittance spectra. The optical band gap of the thin films forx= 0.00, 0.03 and 0.06 can be expressed by (0.84x+2.62) eV, which is due to the Burstein-Moss effect.

In this article, large capacitor charging and discharging experimental system is utilized to generate 270V DC-current by pre-charging to the large capacitor and discharging. Interrupter switching experiments of 540A, 1800A are done in aviation environment, and results of arcing breakdown manner are analyzed and explained. The experiment results indicate that 270V DC-current and arc in aviation environment can be broken by the way of using IGBT in appropriate time; In aviation environment, the breaking capability can be improved, and arcing breaking manner can be used to estimate the arc time constant by several experiments.

Due to the smalle hole of the shale formantion, particles with smaller size, such as nanoparticles was developed to be used as plugging materials during the drilling of shale formation. In this article, poly (styrene-acrylic acid) particles were synthesized by soap-free emulsion polymerization of styrene (St) and acrylic acid (AA). The as-prepared polymer particles were characterized by Fourier transform infrared spectroscope (FT-IR), dynamic light scattering (DLS). In addition, salt tolerance, temperature resistance and compatible properties with additives in drilling fluid of the polymer particles were also investigated.

To provide a theoretical basis for water prevention and control methods and reasonable supporting techniques for vertical shaft, and to ensure the shaft construction to pass the sandstone aquifer safely and rapidly, numerical simulation using dynamic damage constitutive model, which was a user-defined constitutive modules in FLAC3D, a lagrangian analysis code in three dimensions, has been applied to investigate the dynamic damage effect in the surrounding rock of the grouting curtain near the driving working face for vertical shaft excavated by blasting. The results indicate that the distribution of the damage zone in the surrounding rock of the shaft, which decreases the effective thickness of the grouting curtain, was like a ellip-se, and that the depth of the damage zone in the surrounding rock of the shaft grouting curtain is fewer than that of the driving face floor. It can be concluded that the centre part of the driving face floor, especially the cutting hole zones, and the shaft wall in the greater horizontal stress side are the " key parts " for shaft water prevention and control methods.

The Octahedral layer structure manganese oxides (Buserite and Birnessite) have been synthesized and modified by aging a MnOx gel which was produced from the redox reactions between Mn2+ and MnO4- in the presence of other metal cations (Mg2+, Ni2+, Co2+ or Cu2+). The present study investigates the structure transformation between Buserite and Birnessite using X-ray powder diffraction conducted on cation doped manganese oxides at different stages of before and after hydration. The results indicate that introduction of Mg2+ into the interlayer can completely achieve the structure transformation between Birnessite and Buserite after hydrated at 24h, and Ni2+ can partially reverse.

The steering mechanism of tracked vehicles is complicated and large, which is an obstacle for its miniaturization. According to the theory of rubber-belt CVTs, a new kind of steering mechanism for small Tracked vehicle is designed. The mechanism consists of two symmetrical-layout rubber-belt CVTs. A sliding part for steering is designed, which can slide axially to make the transmission ratio of one transmission increase while the other reduces, so that the tracked vehicle turns. The steering motion is calculated and its motion discipline is founded. The steering sensitivity and steering smoothness are analyzed, and its steering performance is evaluated.

The exiting of wind turbines will cause the adverse effect on the power grid and its assembling unit in network voltage drops. So, direct-drive wind power generation system should meet the requirement of the certain ability of low voltage. This paper introduces the influence of wind power system with different structure by voltage drop as well as the disadvantage and advantage on LVRT. The relate regulations based on LVRT are analyzed. The existing LVRT technologies of direct-drive wind power systems are briefly presented. The characteristics of each scheme from the different LVRT technology are analyzed. Moreover, further study of LVRT for PMSG is pointed out.

The feasibility of the launched transport mode is studied by means of the physical and simulation model. And a new transport mode—launched transport mode, is put forward. After describing the overall design thinking, a preliminary design of the aircraft of the transport mode is carried out. Then the result is obtained that the new mode can save 10%~30% on cost and improve 30%~50% on efficiency than other transport modes when undertaking the equal transport task according to flight-test and simulation of the aircraft model. The launched transport mode provides a new mode for the short-to-medium distance transportation, as well as a new idea for the innovation of the transport mode in the future.

The measurement of oxygen content in liquid iron and steel has been a challenge for decades and there have been many attempts to develop oxygen sensor to adjustment the smelting process on the basis of the probe for monitoring oxygen dissolved in molten liquid. However, there was still not a common standards of zirconium tubes about domestic product, which limited their application and improvement This work selected several domestic enterprises oxygen measuring half-cell system to study the relationship between the physical properties and microstructure at room temperature. Furthermore, we also analyzed about the typical performance of the domestic Oxygen content products, which would be beneficial to test and improve the quality of domestic products. Keywords: zirconia tubes, oxygen content, oxygen sensor

Tm doped GdOBr compounds were successfully synthesized through solid-state method. Then bromide ion in the as-synthesized compounds Gd0.97Tm0.03OBr was exchanged by P-toluene sulfonate ion in P-toluene sulfonate sodium solution. A sol-solution was obtained after the ultrasound treatment of intercalating sample in formamide solution. In addition, many rare-earth metal elements can launch visible light when excited. The emissions of Tm3+ at 478nm originated from the transition of Tm3+(1G4→3H6) was observed.

In this paper, the gas sensors using WO3 as sensitive electrode, Pt mixed potential as the reference electrode was researched. The structures and preparation methods of the sensors were introduced. Besides, the sensitive materials, the electrode surface and the section morphologies were characterized by means of SEM and EDS. Furthermore, the sensing properties of the as-fabricated sensors were examined under different NOX concentrations and temperatures (500°C, 550°C and 600°C). The results revealed that the response signal become smaller with the temperature increasing, and stronger with the increasing of the NO2 concentration.

The codes for ejector nozzle with floating external adjustment sheet were specially developed, the flow field was numerically simulated by using parametric modeling method and grid partitioning technique. Turbulence model was selected according to predictions of explicit algebraic Reynolds stress, specific heat ratio (γ) was based on local temperature and gas compositions. The formulas of ideal nozzle parameters were derived using varied γ, which were used to analyze nozzle aerodynamic performance. The results obtained from constant and variable γ were compared. The results show that: nozzle mass flow rate is reduced because of more difficulty in airflow expansion, while nozzle thrust has a tiny change in variable γ cases. Moreover, the high temperature region of inner nozzle is larger and injected cold air is less despite of a smaller balanced floating sheet angle, which are detrimental to thermal protection.

Cu-OMS catalyst reveals well catalytic performance on the oxidation-reduction reactions of gasoline engine exhaust. The catalysts were characterized by means of XRD, nitrogen physisorption and oxidation-reduction reactions. The results of the catalytic tests revealed that CO conversion can get 95% at as low as 150°C and achieve 100% at 200°C through 2CO+O2→2CO reaction, while CH4 and NO conversion can achieve 87% and 90% at 300°C respectively. The Cu-ML corresponds to a type IVisothermal, and Cu-OMS corresponds to a type II isothermal. High Cu dispersion in manganese oxide crystals and low agglomeration are the main reason for high activity.

One sol-gel method is explored to prepare red, green and blue (RGB) fluorescent dyes co-doped nanoporous silica at low temperature in air. All of the dyes covers blue-emitting 2, 5-bis (5-tert-butyl-2-benzoxazolyl)- thiophene (BBOT), green-emitting Coumarin 152A (Coumarin) and red-emitting Lumogen red R305 (Lumogen), contributing to the photoluminescence (PL) of the hybrid. As a key factor, the molar ratio of reactants TEOS/Dioxane/ H2O is 3:12:4 during the sol-gel process. The maximum doping concentration of dyes is the result of dyes dispersing into nanoporous silica, which supported by Infrared Spectroscopy (IR) and X-ray diffraction (XRD) technology. So this sol-gel preparation can enrich the inorganic luminescent materials at a simple style, especially for PL materials or electroluminescent (EL) materials in thin films state.

The effect of surfactant on improving the leaching rate of uranium was studied under both batch and column experiments. Batch experiments show that surfactant DMSS can improve the leaching rate and the the surface tension is decreased about 55.29%. 70 mg/l DMSS has the highest leaching rate of uranium , which close to the micellar concentration of DMSS. In the column study, with the addition of DMSS, the leaching rate of uranium is improved 8.3%. Thus the surfactant DMSS can accelerate leaching of uranium.

Ecological real estate is a re-definition of green building, with its broad conception and inherent realities of social and economic development in the world nowadays. As planning, construction and management of ecological real estate in China is still in the preliminary stage, a method of biodiversity analysis in natural water bodies of real estate is established as a technical way of ecological real estate management.

Joint load transfer ability is the key part of the analysis of the rigid pavement structure. This paper is focused on the load transfer efficiency at joints of monolithic track-bed under new city tramcar loading. Based on the general finite element analysis software ABAQUS, the relationship between the modulus of virtual materials in virtual material layer method and joint load transfer ability is analyzed. Meanwhile, bending stress and deflection for monolithic track-bed structure on edge loading case are calculated under different thickness of the pavement structure.

This paper establishes a lane function allocation model based on the problems that traffic flow is not smooth and traffic is heavy. And choose typical intersection in Hohhot as the research object, using the lane function allocation model to optimize. Optimization results can be very good to improve intersection, which proves the rationality of the lane function allocation model.

With the rapid development of economy, campus logistics industry has rapidly developed. At present, the university logistics has obtained certain achievements, but it also has many problems such as scope of distribution and distribution quality. In order to solve the above situation, we should make full use of campus resources, and establish campus logistics distribution center, to accelerate the process of logistics management for the construction of the campus, and to provide personalized service, logistics for the construction of the healthy and orderly campus environment.

Urban signalized intersections travel delay is an important part of the total traffic delays. To improve the traffic capacity of intersection is of great significance to solve the urban traffic problems. Combining with Hohhot Shi Yang Street Bridge Road and Five Tower Temple East Street intersection, this article had a detailed analysis of the intersection delay. We used the HCM2000 delay calculation model and microscopic traffic simulation software VISSIM to analyze the intersection delay. This is very useful for traffic management and controlling.

Development of smart grid spawned the big data in electric power industry, the cloud computing platform provided the solution for the big data in electric power industry, it has a significant effect for batch jobs, but its real-time is not guaranteed. For the real-time problem of cloud computing platform, the Storm platform will be introduced to monitor the grid power. This paper studies the fair share scheduling algorithm under the Storm platform. It introduced the concept of Storm framework briefly, then, proposed the fair share scheduling algorithm according to the lack of current Storm scheduling algorithm, finally, the experiment proved that the scheduling algorithm based on fair share improved the resource utilization of Storm cluster and reduced the processing delay of the data.

For the bulk amorphous Fe24+xCo24-xCr15Mo14C15B6Y2(X=0, 2, 4, 6 and 17) alloy, the corresponding corrosion properties associated with glass forming ability (GFA) have been carried out. Neutral salt spray corrosion test results show that the Fe28Co20Cr15Mo14C15B6Y2 alloy has the minimum corrosion rate, followed by Fe26Co22Cr15Mo14C15B6Y2, Fe24Co24Cr15Mo14C15B6Y2, Fe30Co18Cr15Mo14C15B6Y2, Fe41Co7Cr15Mo14C15B6Y2 and Ti6Al4V alloys. Specifically, the Fe28Co20Cr15Mo14C15B6Y2 alloy with the highest GFA also has the best corrosion resistance. With the increasing of Co addition, the corrosion resistance of the FeCo-based bulk metallic glasses is first increases and then decreases, which has the same trend of GFA with the change of Co elements. Furthermore, corrosion morphology are different for FeCo-based BMGs with different Co content.

Driving comfort is one of the most important indexes for automobile comfort evaluation. The joint torque calculation model of the lower limb in driving posture is established in the presented work firstly. The relationship between cab layout parameters and the joint torque can be obtained through dynamical simulation in the MATLAB by employing Kane method. A new method based on muscular forces is proposed to evaluate the automobile comfortableness. The force of each muscle can be obtained by employing static optimization algorithm of inverse dynamics. The impact of cab layout parameters , joint torque and the muscular forces on driving comfort and the relationship between them can be found through the analysis. As an reference, these parameters can be used to optimize the cab and offer an important support for its optimization.

As an important active safety control method, vehicle yaw stability control guarantees the dynamic stability of vehicle. A wheel drive vehicle yaw stability controller based on model predictive control theory is designed to plan the longitudinal forces of the four wheels online to control the driving torque or braking torque of each wheel. With the designed controller, the vehicle is able to track the desired yaw rate in the process of turning. The yaw stability and longitudinal characteristics of the vehicle are guaranteed at the same time.

This paper reviews the development history of parallel machine tool and new achievements in China and abroad. Typical methods of error modeling, error detection and error compensation are introduced. After analyzing the biggest problem of recent error compensation technology, this paper prospects the further research trends.

Numerical simulation to the temperature of laser cladding can simulate the process of its technique, which can also optimize the parameters of the technique and predict the defects of the cladding. In this paper, a three-dimensional finite element powder-feed laser single cladding model of the transient temperature field was built based on APDL in ANSYS, where the Gaussian distribution of heat source, forced convection heat transfer and the motion of laser heat source are simulated .The results reveal how the main technique parameters affect the distribution of the temperature, and make a prepare for the experiment of laser cladding.

To solve the problem of irregular leather nesting, a “Revolution-Rotation” algorithm is put forward on the base of heurism search in this paper. The system can be applied in nesting problem in both regular and irregular motherboard, and can achieve the balance of material utilization and nesting efficiency.

Gears are widely used in engineering machinery. Mechanical analysis of the gears matters more much than motion analysis when they are used in heavy machinery or equipment. Dynamic simulation of the meshed gears is based on the theory of contact and impact concerning with the definition of the impact parameters and the model in ADAMS, so the dynamic simulation process is often complicated. In this paper, an effective dynamic simulation method of meshed gears was proposed by analyzing the physical significance of the impact parameters and the calculation method of the impact, and the force curve of the meshed gears was simulated. This result can provide basis for the design and manufacture of the gear.

In recent decade, containers become an important part of the world's economy. With the growth in offshore trade, problems about container and port are attention by research scholars in many countries. In the study on the problem in container ports, Berth Allocation and Quay Crane Scheduling problem are very important; optimization of the two problems can improve the efficient of container ports. In this paper, we describe and classify the main Berth Allocation Processes and Quay Crane Scheduling and present a survey of methods for their single optimization and integrate optimization.

This paper presents an offset-cancellation and low power cascaded comparator with new technique for flash Analog-to-Digital Converters. The improved structure cancels both input and output offset voltage by the feedback from outputs to common inputs. The total current consumption is reduced sharply for a clock circle with 1:2 dutyratio. The improved comparator is implemented in 0.35μm CMOS process. The Spectre simulation results show that the offset voltage of the improved structure is 3.14996mV with σ = 2.0347mV,and total current consumption is 17.59μA, while the offset voltage and total current consumption of the primary one is -5.649mV with σ = 14.254mV and 57.18μA respectively.

This paper proposed an algorithm called “Revolution-Rotation” for two-dimensional irregular leather nesting based on heuristic search. The algorithm simplified the process of searching, constructing an evaluation system which evaluates by the center of gravity of the leather to meet the demands of actual requirement. The nesting test shows that the balance of material utilization and efficiency can be controlled by the adjustment of research parameter.

Urbanization sweeping the world has greatly increased the speed of urban life, and cars become the development trend of modern city. As a consequence, there is a growing number of contradictions within the systems of urban traffic. This article conducted traffic surveys in the West Second Ring road of Hohhot and analyzed the collected traffic data. Analysis to identify the existing problems of the Second Ring Road through the traffic parameters, given the optimization proposal based on the status, simulated the optimization method by VISSIM simulation software as while.

This article took gravity wharf engineering as the object of study to explore its deformation law by using GPS positioning technology. First, we will introduce the layout of a GPS control network at the wharf and then monitor the displacement of the gravity wharf through GPS-RTK、DBS-RTK and GPS static positioning technologies separately. Comparing three groups of monitoring data, we came to the conclusion that this gravity wharf is very stable, which has also proved the feasibility to apply GPS positioning technology to the displacement monitoring of the gravity wharf.

A compiled-type numerical control system based on asynchronous operating mode was proposed. The system constitutes of data center, motion control cards and communication system, solving the contradiction between real-time and openness property. The architecture and work procedure of the system were illustrated. According to the features of system that are large amount of data transmission, high transmission speed requirements and numerous connected devices, data compression technology of NC system was studied. LZW compression algorithm was chosen after contrast, and compression based on PC software was implemented in data center while decompression based on FPGA hardware being implemented in motion control cards. The simulation and experiment results show that data compression ratio could be under 10%, compression and decompression speed are fast and system requirements are satisfied.

The battery ability of recovering electricity plays a significant role in improving the regenerative braking performance. In this paper, a control for recovery of braking energy in Electric Vehicles (EVs) with electro hydraulic brake (EHB) is proposed, which makes the recovery transfer to the electric hydraulic pump of EHB directly, rather than being stored statically in the battery. An energy flow strategy was designed for the maximum braking energy recovery based on this control. The simulation results show higher energy recovery rate in comparison to the general recycling control.

The automatic measuring instrument for the flatness error of the rail wagon is designed with carbon fiber and aluminium alloy, which makes the instrument handy with good stiffness. After the design for the main structure and arranging the position of sensing element, finite element analysis is used to guarantee that deformation of structure itself will not affect the measurement accuracy. The design of the automatic measuring instrument for the flatness error of the Rail wagon takes the place of tradional feeler gauge measurement, raised the work efficiency and improves the measurement accuracy to 0.1mm.

A tool path planning algorithm that generates contour-parallel tool paths for 2D pockets is proposed. 2D pockets with islands bounded by line and arc segments can be handled. The algorithm first generates raw offset loops by vertex offset, then based on the concepts of offset region and invalid edge, local invalid edges are removed. By the character of direction vectors at the intersections of offset tool paths, the invalid sup-loops are removed. The offset tool paths are linked by depth-first traversal algorithm after constructing a single-parent tree. Experimental results are given to verify the proposed algorithm.

A certain thickness of two, three and four layers of axisymmetric finite element bellows model were built by Abaqus firstly. Then the axial stiffness and stress and strain distribution of multi U-shaped bellows were simulated by finite element analysis. The results showed that in the case of a constant thickness, with the increase of the number of layers of the bellows, the stiffness of the bellows would be significantly reduced, and in the case of large deformation, the overall stiffness of the bellows would change significantly and was divided into elastic stiffness and plastic stiffness.

Subgrade soil is very important materials to support highways. Resilient modulus (MR) has been used for characterizing stress-strain behavior of base or subbase subjected to repeated traffic loadings. Several methods to estimate the resilient modulus were suggested in the past years. The main objective of this study was to test the resilient modulus in the laboratory. The Subgrade soil was selected in Henan province. Resilient modulus tests were conducted with UTM. Additional analysis was performed to discuss the factors of the test results.

The functional study of artificial heart valve has the positive significance on the postoperative care of the patients with valvular heart disease and the precaution of postoperative complications. The analysis of the heart sounds is the most direct way to estimate the function normally of heart. Because of the heart sound is nonlinear and nonstationary. Compared with the normal method of time-frequency analysis, Hilbert-Huang transform can analyze the nonstationary and nonlinear signals more accurate and more effective. Hilbert-Huang transform is introduced to the functional study of artificial heart valve. It used for extracting the inherent characteristics. Using the empirical mode decomposition (EMD), the heart sound was decomposed into a series of intrinsic mode functions (IMF). The Hilbert spectrum was established by the calculating results of these IMFs. The Hilbert spectrum has the characters of time-frequency-energy, and then the marginal spectrum was structured. Comparison with the characters of pre-operation and post-operation was used for reveal the function of artificial heart valve. At last, we use the short-time average energy and the short-time average range to verify the credibility of Hilbert-Huang transforms method. The result of simulation show that this method was well analyzed the function of artificial heart valve.

Stereo matching has been the focus of computer vision research. Some current researches on stereo matching algorithms were summarized, the stereo matching key techniques were analyzed; View of the current major challenges on binocular stereo matching, elaborated matching algorithm possible solutions and modification approaches; Finally, the field of technology development are prospected. © (2014) Trans Tech Publications, Switzerland.

The control object is the temperature of pre-cooling machine, combined the advantage of neural network and genetic algorithm (GA). Adopting GA controller based fuzzy neural network. The controller doing the fuzzy reasoning to the difference of given temperature and sample temperature. GA does the offline training to the Connection weights and Membership function of fuzzy neural network, then uses BP algorithm to do further adjust online for parameters. Simulation result shows that the new controller achieves better control effect compared with traditional PID controller, fuzzy controller.