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Nowadays, microstructures have an important role in optical products as well as in optical systems. Beside machining methods, hot glass embossing is recently a novel technology to manufacture microstructures in optical components with high quality and low cost. Especially, this technology has been assisted efficiently by ultrasonic vibration. Previous studies showed that high energy of ultrasonic vibration would lead to the temperature rise inside the glass so that the material was easily embossed into the microcavities on the mold. Thus, micro-formability of glass material has been especially improved efficiently. However, there were no studies focusing on effect of ultrasonic vibration on embossing speed in this process. Therefore, this work is aimed to utilize ultrasonic vibration to improve the embossing speed of hot glass embossing process. K-PSK100 optical glass was used as the material for all experiments. Pyramid array with size of 30 × 30 × 20 μm and period of 150 μm was created on the mold. Microstructure hot embossing experiments were conducted for both conventional process (without ultrasonic vibration) and ultrasonic vibration-assisted process (frequency of 35 kHz and amplitude of 3 μm). By fixing the embossing temperature of 430 °C, the embossing speeds of 0.05 mm/min, 0.10 mm/min and 0.15 mm/min were applied, respectively. Experimental results showed that in case of conventional process, the faster embossing speed, the smaller final height of pyramid structures. Nevertheless, this obstacle was resolved by ultrasonic vibration. Under heating effect of ultrasonic vibration, the glass still filled well into the pyramid cavities on the mold even when the high embossing speed was applied. Measurements indicated that in the same experimental conditions (temperature and speed), ultrasonic vibration could improve the filling ability of the glass to 18 %. This finding could be used to optimize the experimental conditions to increase the productivity of the microstructure hot glass embossing process.

This paper presents a new method, called data fitting method based on numerical results, to calculate the contact deformation between logarithmical crowned roller and raceway of rolling bearings. First, the contact deformations between logarithmically crowned roller and raceway are analyzed and numerically calculated according to influence coefficient method, and then a fitting formula based on the calculated contact deformations is obtained by means of multiple linear regression method. The formula includes the dimensions and logarithmic crowned parameters of bearing together with the load parameter, and can be used for fast calculation of contact deformation between logarithmical crowned roller and raceway in low and medium load conditions, so that the formula is suitable to efficiently analyze the dynamics characteristics of arbitrary logarithmic crowned rolling bearing.

In this paper, the influence of pre-strain on low-temperature gas carburization of 316L austenitic stainless steel was investigated. A group of flat specimens were uniaxial tensile to several levels of pre-strain including 5%, 10%, 15%, 20% and 25% engineering strain. Then, the pre-strained specimens was treated by low-temperature gas carburization at 470 °C for 30 h. In order to elucidate the effect of pre-strain on low-temperature gas carburization, optical microscopy (OM), X-ray diffractometer (XRD), scanning electron probe micro-analyzer (EPMA), microhardness tester and residual stress analyzer were used. Meanwhile, dislocation density of the pre-strained specimens was semi-quantitatively measured by means of X-ray diffraction analysis and the role of dislocation density on carbon diffusion during low-temperature gas carburization was discussed. The results show as follow: (1) the thicknesses of the carburized layers are independent of the pre-strain degree. (2) dislocation density increases with the increasing pre-strain, but almost has no effect on carbon diffusion at the given carburizing temperature. (3) an outstanding surface with hardness (≈ 1150 HV0.1) and compressive residual stress (≈1900 MPa) is introduced by low-temperature gas carburization, and the strengthening results of carburization are unaffected by pre-strain.

The aim of this study is to examine the complicated dynamics behavior of nonlinear vibrations of bistable cantilevered piezoelectric beam. The base excitation on the beam is assumed to be harmonic load. The Galerkin’s approach is adopted to disperse the energies and the virtual work. Dynamic equation of the bistable piezoelectric system is established by using Hamilton’s principle. The averaged equations in the polar form is obtained by using the method of multiple scales. Based on the actual work situation of the cantilevered piezoelectric beam, it is known that base excitation and the size parameter of the beam play the important roles in the nonlinear vibration of the cantilevered piezoelectric beam. The quality of the permanent magnet, the thickness of the base layer and the length of the beam all affect the amplitude of the beam. The thickness of the piezoelectric layer can make the frequency response curve shift in frequency domain.

This article focuses on the complicated dynamics behavior of the nonlinear vibrations of the bistable cantilevered piezoelectric beam. The base excitation on the beam is the harmonic load. We studied the jump phenomenon of the system by sweeping the voltage and displacement, the experimental results show that the bistable piezoelectric cantilever beam reflects the obvious hard spring characteristics. In addition, the influence of the distance between the magnets and the thickness of the piezoelectric layer on the dynamic behavior also being studied. Experimental results show that the distance between the magnets is closely impact on the nonlinear dynamic responses of the system, there is an optimal distance between the magnets causes the most complex dynamic behavior in frequency domain. System appears period doubling bifurcation into chaos many times when the distance between magnets is appropriate.

The autonomous stratagem combines the concepts of traveling salesman problems (TSP), radio frequency identification (RFID), E-compass wireless networks sensors and the evolutional particle swarm optimization (PSO) to identify the optimal routing paths in the dynamic indoor space. A desired the setting lot as soon as possible. Four active RFID tags amounted in the rectangle type environments and indication of E-compass are proposed to identify the robot position. The routing concept of the TSP is developed by the evolutionary PSO learning scheme to approach the valid routing-path of the mobile robot. The developed mobile robot system, with the proper number of fuzzy membership functions, simultaneously achieves the multiple objectives of avoiding obstacles by the selected shortest routing path.

Benzoylformamide (BFA) derivatives are proposed as new photocaged bases. Initially their abilities as photoinitiators to initiate the free radical photopolymerization of acrylic monomers have been investigated. Next, we detail regarding the model photopolymerization in the presence of BFA-dBA (N,N-Dibenzyl-2-oxo-2-phenylacetamide) as a photocaged base. In combination with a benzoyl peroxide initiator, BFA-dBA is able to initiate the amine-mediated redox photopolymerization of acrylates, and photopolymerization rate is markedly enhanced.

In this paper, we report a synthetic method to prepare vegetable oil-based polyurethane acrylate (PUA) resin, which can be used in photo polymerization coating, ink and other fields. First, the mercaptoethanol was introduced into castor oil via thiol-ene photo-click reaction with UV irradiation, forming polyhydroxy compounds, then we added the isocyanate acrylate, which was obtained by the reaction between hydroxypropyl acrylate (HPA) and isophorone diisocyanate (IPDI), into polyhydroxy compounds, the molar ratio of HPA and IPDI is 1:1. Finally, we get the castor oil-based polyurethane acrylate. Different functional acrylate can be obtained by adjusting the hydroxyl content. Furthermore, the structure and performance of Polyurethane acrylate was confirmed by FT-IR and TG. The water absorption and adhesion of synthetic polyurethane acrylate were tested. Meanwhile, the thermal stability was studied. The results indicated that the thiol-ene addition reaction was proceeded and compared to our previous studies, the properties of cured film are greatly improved, especially the hardness and thermal stability.

Compared with the lithography and traditional technology, ink-jet printing technology has huge advantages such as reducing costs, improving production efficiency and reducing environment damage. The silver nanoparticles conductive ink used as core material in ink-jet printing technology has been greatly developed. At present, the conductive inks for printed circuit usually has high sintering temperature, low adhesion, poor mechanical properties, high cost, which limit the further industrial application. In this paper, nano silver pulp was prepared through liquid phase reduction method, and a self-made protective agent ensured that the particle size distribution of silver particles is about 5nm. The above silver pulp was dispersed in the organic resin to get conductive ink with 20% (wt%) silver content. Under 170°Csintering, the electrical conductivity of the ink layer was 1.15×104S/m.

Image segmentation and feature extraction are the premise for machine vision system to analyze and identify the image. Threshold image segmentation algorithm according to the method of two dimension threshold has a lot of calculation in calculating the threshold, and the minimum error threshold method can not use the spatial information of image. This paper presents an improved quantum-behaved particle swarm optimization based on the night segmentation and feature extraction technology. This paper introduces the QPSO algorithm based on multi group and multi stage improvement. The QPSO optimizing algorithm gradually approaches the global optimum threshold value to achieve better convergence and stability. An algorithm of vision image segmentation and feature extraction based on improved quantum-behaved particle swarm optimization is designed. Experimental results show that the optimization process of this algorithm has less control parameters and faster convergence speed.

In order to develop north seeking system with strong anti-interference ability, the influence caused by the swaying base on the performance of north seeker was investigated. The influence of sinusoidal signal of gyros and tilt sensor's output was analyzed based on four-position north seeking system which was consisted of a single axis gyro and a tilt sensor. Fiber optic gyros and tilt sensor are interference by the same vibration signal, according to the relationship between the output signal of gyro and the angle sensor, a PI controller was designed to compensate the gyro's output error. This real time compensation can effectively improve the north seeking accuracy and speed without complicated calculation or external reference signal. The north seeking accuracy is better than 0.03o. Simulation and actual north seeking result proved that this method significantly improves the north seeking performance in vibrant environment.

This paper presents the circular-arc tooth profile that has no trapped-oil feature and flow fluctuations. The mathematical model of tooth profile and helical surface is obtained by gear engagement theory. The examination of helical surface is by coordinate measuring machining (CMM). The sections that perpendicular to the axis direction of gear are selected to obtain the trajectory of measuring ball by the starting points and end points of measuring ball. The examination process of CMM is simulated by Matlab in this paper.

This paper Introduced A horizontal Sanding Machine That is used for powder processing, it is supported by frame, main shaft components, mixing grinding mechanism, cooling circulation system of four parts, mixing grinding mechanism consists of a grinding disc and separating the rotor. Grinding disc wheel hub and the outer ring plate supported by three spokes. The spokes have the effect of rod pin, so the grinding disc has the effect of disc and rod pin type Sanding Machine. Cylinder inner cylindrical surface treatment of semicircle spiral groove, outside cylinder liner and cylinder inside the cylindrical surface with connection, form a cross section of semicircle spiral groove cooling circulation channel, to avoid short circuit in cooling water circulation and cooling effect is good.

At junction of Heng dong Count Shi Ji Road and Zang Qing Road, its subgrade soil is almost miscellaneous fill. Based on the analysis of the basic characteristics of miscellaneous fill subgrade and the local climate and traffic load, we apply the Dynamic compaction method consolidate to the Miscellaneous fill foundation and replace the conventional road with continuous reinforced concrete pavement (CRCP). This paper provides the Continuous reinforced pavement design method and a reference for similar projects.

An important thiol ester photosensitive monomer COMP (CO-based mercaptopropionate) was prepared via melt polycondensation method using castor oil (CO) and 3-Mercaptopropionic acid (3-MPA). Structure of the thiol-compounds was characterized by FT-IR, 1H-NMR. When the thiol compound was used as photosensitive monomer and polyurethane-acrylate prepolymer was used as main material in UV curable adhesive. The UV curable adhesive showed good curing behaviors and thermal stability with curing time 100s, T-peel strength 3.8N/25mm and shrinkage rate 8%; so the UV curable adhesive could meet the requirements for flexible packaging composite.

Industrial design has been developed in China for decades, it is with the constant collision of traditional Chinese culture and learned a variety of nutrients. Increasingly focused on product design aspects of traditional culture. Meanwhile, the product experience has become the core of the product design evaluation criteria. Many aspects of traditional culture will affect the user experience on the use of the product.

The location of Su prince tomb of Ming dynasty followed the geomantic site selection principle in ancient times. The tombs which were surrounded with mountains and the water formed the environment of hiding the wind and gathering the water. Through to the geomantic pattern's research and the discussion of Su prince tomb geomantic site selection, this article proposed that the thought of coordinated with nature and the idea of ecological and sustainable development.

This paper describes rough neural network which consists of a combination of rough neurons and conventional neurons. Rough neurons use pairs of upper and lower bounds as values for input and output. In some practical situations, it is preferable to develop prediction models that use ranges as values for input and/or output variables. Integrating rough set theory with neural network theory, a novel information fusion method based on rough neural network is proposed to fuse the different-source images in agricultural robot. It is used to fuse infrared and visible images in order to take full advantage of the complementary information between infrared and visible images. Experimental results show that the fusion effect and speed are both better than standard wavelet transform and the conventional neural network.

Based on the shoes design methods and processes of analysis and summary, the computer-aided design as a design tool to intervene to determine concept , design performance and design verification stages. TO build a market to meet customer needs as the guiding ideology of the computer-aided design system shoes finally.

This paper presents a bandgap reference and an output-capacitorless LDO regulator with adaptive power transistors. The bandgap reference consists of a current reference circuit, a bipolar transistor and proportional-to-absolute-temperature (PTAT) voltage generators. The proposed LDO improves load transient and light load efficiency by permitting the regulator to transform itself between 2-stage and 3-stage topologies, depending on the load current condition. Cadence simulation with SMIC 0.18 μm process shows that the bandgap reference generates a reference voltage 569 mV and the quiescent current is only 0.23 μA, the proposed LDO generates an output voltage 1 V, the quiescent current is 0.88 μA (including bandgap reference) at no-load condition, the undershoot /overshoot voltage is 187 mV/152 mV and the settling time is 5 μs as load current suddenly changes from 0 to 100 mA, or vice versa.

With the higher requirement for clock accuracy in power system, the accuracy and stability of wild area punctuality in GPS cannot meet the demands of the high–precision measuring instruments in power system. Firstly, this paper establishes the mathematical model of crystal oscillator clock error using polynomial fitting method. Then, it estimates the parameters of polynomial model with generalized least squares method. Thirdly, it updates the error-model of crystal oscillator clock dynamically for modifying its predicted error. The result shows, this method can not only predict accurate time error, but also filter out random errors well in GPS.

With the reduction of fossil resources, renewable raw molecules have drawn a great deal of attention because of their ability to substitute for petrochemical-based materials. In this context, we synthesis a soybean oil based polyfunctional acrylate (PFA) by thiol-ene photo-click reaction and DCC catalyzed esterification in mild environment for UV-curable materials. Chemical structure was confirmed by 1H NMR and FTIR. Thermal and mechanical properties were respectively revealed by DSC, TG and TMA. All the cured films possessed excellent thermal stability and UV-curing performance, implying that they can be used for high-performance UV inks and coatings of packing industry, especially for ink-jet inks.

Linear feature detection in digital images is an important low-level operationin computer vision that has many applications. In remote sensing tasks, it can be usedto extract roads, railroads, and rivers from satellite or low-resolution aerialimages,which can be used for the capture or update of data for geographic information andnavigation systems. In addition, it is useful in medical imaging for the extraction ofblood vessels from an X-ray angiography or the bones in the skull from a CT or MRimage. It also can be applied in horticulture for underground plant root detection inminirhizotron images.

In order to guarantee the quality of remanufacturing planetary gearbox products, fault diagnosis and evaluation are the key links in the process of remanufacturing engineering. The faults will lead to cyclical impact, causing the transient response of periodic vibration signals, by studying the fault mechanism and using modern signal processing methods, the fault features can be extracted and analyzed. The purpose of this review is to present a summary about the application of the vibration test technology in remanufacturing planetary gearbox fault diagnosis, including the following main aspects: the fault diagnosis theories,the sidebands spectrum structure and the application of modern signal processing methods. In addition, some key problems in planetary gearbox fault diagnosis are analyzed and the approaches to solve these problems are discussed.

Haze reduction is actually an ecological problem influencing the urban and rural construction, which should not only meet the demands of people, but also remain the space for the future modification and update. Urban and rural construction should combine with the contents, methods and principles of ecological urban and rural construction in practice, developing new thought of urban and rural construction to improve ecological environment protection, which lays the foundation and creates the condition for further improvement of harmonious urban and rural construction.

Plate heat exchanger with unique advantages become dominant heat exchange equipment in heating engineering. But there is no heating regulation formula of plate exchanger applying in indirect connection hot water heating central heating regulation. This paper analysis the condition that the heating user’s system adopts quality regulation method and the hot water network system adopts quality-flow regulation method, obtain the regulation formulas of plate exchanger applying in indirect connection hot water heating central heating regulation, provides reliable theory basis on the operation regulation, energy –saving testing, etc. for indirect connection central heating system.

This paper aiming at absorption heat pump maximizing annual heating quantity, with the goal of thermal power plant absorption heat pump heating earnings in different heating regulation mode, set up calculation model of absorption heat pump heating earnings, analysis heat-supply network backwater temperature fluctuations and heat pump heating quantity difference in different heating regulation mode, discuss optimization approach of absorption heat pump taking basic heat load city heat-supply network heating regulation, calculate heat pump heating earnings finally. The results showed that the pure quality regulation can get the best economic benefits of absorption heat pump.

Based on the regulating principles, the modes of joint regulation and storage of surface water and groundwater in Rushan River Basin are simulated using multi-objective programming method. The study suggests two modes as “two dry years and one normal year” and “four dry years and one wet year”. The results indicate the guarantee rates of water supply are improved, with increasing the exploitation quantity in dry years and the recharge in wet years. The study provides a strong guarantee for water resources regulation and promotes the sustainable development of regional water resources.

The answer extraction model has a direct impact on the performance of the Automatic Question Answering System (QA System). In this paper, an answer extraction model based on named entity recognition was presented. It mainly answers specific questions whose answers are related with the named entity. Firstly, it classified the questions according to answer types. And then it identified named entities with suitable types in the fragmented information. Finally, it got the final answer based on scores. The experiments in the paper proved that the model could accurately answer the questions provided by Text REtrieval Conference (TREC). Thus, the proposed model is easy to implement and its performance is good for specific questions.

Recent advances in synthesis and controlled assembly of monodisperse colloidal nanocrystals into superlattice structures have enabled their applications in optics, electronics, magnetic storage, etc. Morphology controllable silver nanoparticles exhibit numerous unfamiliar characters and have achieved extensive applications in many fields. When applied in solar cells, the silver nanoparticles are used as a catalyst in the preparation of silicon-based antireflective layers, and also the varied morphology silver nanostructures can be utilized for silver paste which makes up the electrode. During the applying process, the size and morphology of the silver nanoparticles are important factors which influence their properties. The paper introduces the morphology category and preparation method of the silver nanoparticles. The effects of the morphology of the silver nanoparticles on their properties are discussed, and the further development of their application in solar cells is prospected.

Association analysis of the production process data (PPD) can be discoveried on the quality relevant parameters with great impact, however, it’s different from correlation analysis of other fields, Huge amount of data due to the production process, and the many parameters involved in the production process, the existing association analysis algorithms as they deal with inefficiency, can not meet the practical application. This paper proposes a new process for the industrial production of efficient data association algorithm-AprioriMask, after the actual production process of association analysis verification, AprioriMask algorithm has significant performance improvements to meet the industrial production process data for correlation analysis.

Motion Vector Prediction (MVP) plays an important role in improving coding efficiency in HEVC, H.264/AVC and AVS video coding standard. MVP is implemented by exploiting redundancy of adjacent-block optimal coding information under the constraint that MVP must be performed in a serial way. The constraint prevents parallel processing and MB pipeline based on LevelC+. In multi-stage pipeline, to some extent, adjacent-block best mode-decision information can hardly be obtained. In this paper, we propose a new hardware-oriented method to improve the coding performance at a cost of few hardware resources. When adjacent block is not available, spatial motion vector prediction (SMVP) for integer motion estimation (IME) and fraction motion estimation (FME) will take the IME best mode information and FME best mode information of left block as best information to derive PMV (Predicted Motion Vector) for current macro-block or block. Experimental results shows that the method we propose can achieve a better performance than the existing methods by 0.1db for the cases with intense movement and a non-degrading performance for flat cases.

This paper presents a capacitor-less CMOS low dropout regulator (LDO) with a push-pull class AB amplifier, and a fast transient controller to achieve a better transient response. The undershoot/overshoot voltage and the settling time are effectively reduced. Through the theoretical analysis of the circuit, cadence simulation with SMIC 0.18μm process and under the condition of the input voltage range 1.4~4 V shows the output voltage is 1.2 V, with the fast controller the total quiescent current is 8.2 μA, the undershoot /overshoot voltage is 97 mV/47 mV and the settling time is 0.3 μs as load current suddenly changes from 1 to 100 mA, or vice versa. Compared with this paper without fast transient controller, the undershoot voltage, the overshoot voltage and the settling time are enhanced by 30%, 64% and 80%, respectively.

This paper based on the feature of Beijing urban rail transit sectional passenger flow, combined with Elman neural network. After carrying out modeling experiment many times, a reasonable forecast model about the prediction of urban rail transit sectional passenger flow was established. Then the Elman neural network model was used to predict the sectional passenger flow of Beijing Subway Line 1, from Xidan station to Fuxingmen Station. At last the output results was compared with that of BP neural network, the result shows that the Elman neural network is more precise and effective than the BP neural network in the prediction of urban rail transit sectional passenger flow.

Based on a prestressed concrete continuous rigid frame bridge reinforcement project, the finite element model of the bridge was established, which includes two kinds of work condition of before and after bridge reinforcement. The finite element model had analyzed the change of natural frequency, deflection and bending stiffness after the web reinforcement of a prestressed concrete continuous rigid frame bridge, in which we have got analysis results that web reinforcement bridge deflection is less than before reinforcement, and the changing law is obvious as inversely proportional relationship, at the same time, the changing law of natural vibration frequency of web reinforcement bridge and original bridge is not obvious, so only deflection but natural vibration frequency can effect evaluation of web reinforcement of continuous rigid frame bridge.

In order to guarantee the stable operation of the highway network, improve the ability of handling highway emergencies and the public service level, and give full play to the advantage of the video surveillance system in finding and confirming traffic emergencies in time, most provinces are gradually improving the construction of provincial networking platform for the highway video surveillance, and based on it, acceleration of the construction of the national highway video surveillance networking platform is needed to strengthen the coordination and management of road network in the region and the ability to command. In this paper, based on current highway video surveillance network system structure and integration technologies, and the problems that the construction of the national highway video surveillance networking platform is facing, through in-depth study of the solutions, the development ideas with strong feasibility are provided to guide the construction of national level platform, which will ensure that the platform is practical and scientific.

This research based on the total amount control of river basin water pollution reducing, and with YiTong river basin as the study case, to obtain the optimal decision scheme of water environmental pollution control, acquired in 2015 the smallest reduction of COD and ammonia nitrogen is 77804.53 tons and 6644.92 tons, in 2020 obtained the smallest reduction of COD and ammonia nitrogen is 33518.49 tons and 2887.69 tons; acquired in 2020 the smallest reduction of COD and ammonia nitrogen is 77103.39 tons and 6584.52 tons, in 2010 obtained the smallest reduction of COD and ammonia nitrogen is 34219.62 tons and 2948.09 tons, provided decision-making support for the basin water pollution control, improve watershed management and control of water pollutants.

Excessive large gap of joint between caissons easily lead to the rear backfill leaking into harbor basin, to cause a differential settlement of the rear terminals and even affect the structural stability. With the case about caisson wharf of a harbor in southern China, this paper puts forward a rehabilitation technology of caisson joints with mold bag concrete as the major filler. The key technologies are introduced in detail including the mold bag production and installation, the height computation of laminated pouring of concrete and underwater concreting, etc. This technical maintenance is reasonable in economy and practicable in technology, worthy of promotion.

Scattering units or building blocks are the basic elements for photonic crystal lattices. Photonic bandgaps can be tuned and improved in two-dimensional (2D) triangular lattices, as well as in square lattices by introducing axial-symmetry cylinder-segments instead of cylinders as basic scattering units. Owing to the changes of bulks, reflectance effect of electromagnetic waves will be different both in TE modes and in TM modes. The widths of bandgaps for the two polarization modes can be adjusted and matched to overlap in some range.

Global warming is becoming a serious problem nowadays. The emissions of greenhouse gas from vessels draw great attentions. As a significant research part of vessel seakeeping performance, resistance capability exert pretty effect on energy consuming. A Wigley ship model is set as the object to compute constraint and free model in calm water and head waves on resistance and hydrodynamic potential coefficients by STAR-CCM. Differences are discussed between both models. Effects on calculation of hydrostatic resistance ignoring trim and heave are revealed .Wave added resistance of free model is computed and compared at different amplitudes and wavelengths. How trim and heave matter the computed results are discussed. So does how wavelength and amplitudes influence total resistance is considered.

Because the direction goals of the snake robot are different in applications, e.g. the target point and target path, the direction control of a snake robot is a challenging problem. We have proposed a control method, which is called passive creeping based on the energy balance. In this paper, the direction of the snake robot which is controlled by the passive creeping control method is discussed. A new direction control method which is based on the torque compensation is proposed. The direction control method set a universal direction goal for all the applications. The torque of the head joint which leads the locomotion direction is adjusted by the torque compensation. The compensated torque decreases the angle between the direction of the body axis and the expected direction by the exponential decay function. In simulation, the trajectory and the angle express the process of direction adjustment. The error analysis proves the validity and adaptability of the proposed direction control. Also the validity of the proposed method is proved by the experiment which is based on the virtual/physical mixed experimental system.

By analyzing the relationship of the design parameters of NYD contact backstop, the cross-section curve of the wedge block has been discussed as Archimedes spiral, logarithm spiral and arc. Each curve is designed optimally using MATLAB optimization toolbox. The merits and drawbacks of each curve are discussed.

This paper aims to experimentally study static responses of bridge longitudinal truss, and the distribution rules of the structural and local stresses were analyzed. The results of the analyses on experimental data show that the typical details in the longitudinal truss concentrate to a limited area on the toe of a dominate weld at the intersection among the upper chord or bottom chord, diagonal and the gusset plates; with boundary conditions being strengthened, stress distribution of the tested specimen became flat and the monolithic tress level decreased relatively. Based on obtained test information, the results are used for updating and validating this kind of structural model, and determining the parameters of finite element model.

Introduces a STC89C51 microcontroller core with the speed of measurement and control system, the system can control the motor starts and stops, either manually or automatically adjust the duty cycle to control the motor speed is set by the Hall sensor data, for motor speed is measured to calculate and display the current motor speed in real time on the LCD. The system is made in the actual measurement with good results, as the research engine performance provides an important reference, so that the entire digital measurement speed system can be widely used, there is a strong practicality.

In this paper, the cogging torque, airgap flux density, back-emf, and losses of a surface-mounted and a hybrid magnetization interior brushless machines with the same stator, airgap width, armature core length, material, permanent magnet consumption, speed and copper loss are compared. The analysis reveals that the loss in rotor back iron of interior motor is higher than that in surface-mounted motor due to the skin effect while the eddy current losses in sleeve and magnets of surface-mounted motor are significant, causing the total losses of surface-mounted motor are higher than that of interior motor.

A bridge is a structure built to span physical obstacles such as a body of water, valley, or road, for the purpose of providing passage over the obstacle. As critical transportation junction in the transportation network, bridge controls the traffic capacity of the transportation network. In the past decade, collapse of highway bridges caused by natural hazard and human error occur frequently. There are three main reason of collapse: 1) overloading; 2) construction deficiency; 3) imbalance of the system safety. In this paper, a collapsed bridge in Harbin is studied based on probability. A reliability analysis is conducted to investigate the system safety of the case bridge under combined effect of overloading and construction deficiency. Some suggestions for bridge quality control are proposed.

High-speed slotless permanent magnet brushless motor based on soft ferrite adopts a large effective air gap structure. For the large effective air-gap, the air-gap flux distribution becomes uneven and the end leakage flux significantly increases. Thus, the traditional analytical method of the phase EMF is inapplicable. This paper deduces the analytical expression of the phase EMF based on the analytical calculation of the air-gap field and analyzes the distribution of the end leakage flux by 3D finite elements methods. Then the end leakage flux is considered by a correction factor of the core length. Finally the analytical calculation method is proved to be feasible by the comparison between the finite elements results and the prototype test results.

In this paper, the conditions and method of constructing the stiffness distribution function of various parameters indeterminate beams by the fundamental mode and specified polynomial density distributing function were made up. It is discussed that the constructed stiffness distribution functions are positive functions in case with different density distributing.

In order to eliminate steady-state speed error of PMSM backstepping control system, an integral backstepping speed control algorithm is designed in this paper. By adding speed error integral factor in the speed Lyapunov function, the speed error can finally converge to zero when PMSM operates in steady-state. On this basis, an integral backstepping speed control algorithm based on RBF neural network compensation is proposed for PMSM backstepping control system used for high-altitude electric propulsion system which is vulnerable to load torque variables. The integral backstepping speed controller based on PMSM reference model can ensure global asymptotic convergence of the whole control system. In order to achieve fast robust adaptive control, the RBF neural network is adapted to online compensate dq axis current error produced by the reference speed and load torque changes. Simulink simulation results verify the feasibility of the given algorithm.