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The existing safety evaluation of high-speed milling cutter mainly based on ISO15641 standards, which by idling experiments, then analysis and determine centrifugal force conditions what cause permanent deformation and fracture destructive of cutter, this method cannot be forecast and control the dynamic evolution of the milling cutter's safety and reliability, when cutting load changed suddenly.This paper using the high speed milling cutter's failure criteria and safety margin model of cutting hardened steel, analysed and evaluated coupled thermal field distribution caused by hardened steel surface feature that changed frequently and cutter's impact, fatigue, strength, stiffness, safety margin which cuased by mutated shock load of cutter, then forecast safety and reliability of high-speed milling cutter, and proposed the control method of safety and reliability that could milled hardened steel in high speed.

The existing processes of controlling machining error just controlled the maximum error. However, it did not effectively control the distribution of the error.The reliability of the assembly precision of the key joint surface did not meet the requirements, thereby affecting the service performance of machine tool. To solve this problem, the error matrix and transformation matrix was used to ascertain the location of joint surface positioning error occurred. The influence of processing error on the the positioning accuracy of machine tool was analyzed. The control objective of milling process was proposed. At the same time, the effects of cutting parameters on the processing error were also studied according to the milling experiments. The process error and its distribution characteristics of joint surface were obtained by analyzing the relationship between deformation of joint surface and cutting parameters. The milling process control methods were proposed.

Existing research on machined surface topography, only consider its response to vibration or wear certain factors, both vibration and wear impact on machined surface topography exist ambiguity and uncertainty, it cannot solve the design conflicts of machined surface topography. For this, this paper analyzes blade installation error, tool wear, vibration and deformation to reveal effects of tip space trajectory, build a three-dimensional model of machined surface topography in simulation, extract its characteristic parameters, by simulation of different amplitudes and wear, found that axis amplitude is a key factor affecting surface residual height, flank wear affects contour distribution distance significantly, by specimen milling experiments, use vibration measuring instrument and ultra-depth microscopy to obtain vibration, wear characteristics and machined surface topography parameters under different cutting parameters, then use the gray system theory to get correlation analysis of the test data, results showed that the influence of tool wear on machined surface topography is prominent than tool vibration.

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.

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.

Real-time measurement system possesses high real-time demand which multithreading technology can largely satisfy, because multithreading technology can implement many tasks at the same time and make largely use of the multiprocessor unique advantages. The paper adopts multithreading programming method to improve the real-time system and it achieves significant design effect. (2013) Trans Tech Publications, Switzerland.

A timing component is developed in order to achieve the synchronization between measuring system and external devices. The function of timing system, as well as the data switching driver based on twin port RAM and interrupt response driver developed by using DDK (Driver Development Kit), are introduced in this paper. The timing component has been used to ensure the synchronization between measurement system and vessel devices, and successfully applied in angular distortion measurement systems. (2013) Trans Tech Publications, Switzerland.

A new real-time measuring system based on video image is developed in this paper. By using the self-collimating collimator, the reflex light-tube and other devices installed on deck, the bi-dimensional dynamic distortion can be achieved by the video interpretation system. The video interpretation system incepts two video signals coming from two CCD of photoelectric self-collimation parallel optic equipment. Real-time video image processing and interpretation, as well as dynamic miss distance are achieved by using concurrent working mode, and the relative distortion of vessel can be obtained by combining the two measurement results.

A new real-time angular distortion measurement system, composed of devices i.e. the photoelectrical auto-collimating collimator and the reflex light-tube installed on deck, is developed in this paper. Real-time measurement of vessel's bi-dimensional angular distortion is achieved by using this computer control system. Two video signals of photoelectrical auto-collimating collimators are received by the computer control system, and real-time image processing is done to obtain the dynamic miss distance. Then relative distortion of vessel is calculated by overlying measuring results of these two-way images. (2013) Trans Tech Publications, Switzerland.

Seeing that human face features are unique, an increasing number of face recognition algorithms on existing ATM are proposed. Since face detection is a primary link of face recognition, our system adopts AdaBoost algorithm which is based on face detection. Experiment results demonstrated that the computing time of face detection using this algorithm is about 70ms, and the single and multiple human faces can be effectively measured under well environment, which meets the demand of the system. (2013) Trans Tech Publications, Switzerland.

A new video image interpretation technology applied mainly to the angular distortion measuring system of navy vessel is developed in this paper. The video interpretation system incepts two video signals coming from two CCD of photoelectric self-collimation parallel optic equipment. Real-time video image processing and interpretation, as well as dynamic miss distance are achieved by using concurrent working mode, and the relatively distortion of vessel can be obtained by combining the two measurement results. (2013) Trans Tech Publications, Switzerland.

An optimization design system for fir-tree root of turbine blade has been developed in this paper. In the system, a parametric model of the blade and rim was established based on the parametric design language APDL, and nonlinear contact method was used for analysis by ANSYS, meanwhile some optimization algorithms, such as Pattern Search Algorithm, Genetic Algorithm, Simulated Annealing Algorithm and Particle Swarm Optimization, were adopted to control the optimizing process. Five cases of manufacturing variation in contact surfaces between root and rim were taken into account, and the design objective was to minimize the maximum equivalent stress of root-rim by optimizing eight critical geometrical dimensions of the root and rim. As a result, the maximum equivalent stress of root-rim decreases markedly after the optimization in all cases. In consideration of both precision and computing time, particle swarm optimization is assessed as the best algorithm to solve structure optimization problem in this work. Corresponding to five different cases of manufacturing variation, the maximum equivalent stress of root and rim reduces by 7%, 8%; 27%, 24%; 27%, 22%; 25%, 19%; 10%, 14% using the Particle Swarm Optimization.

The research on structure optimization for the fir-tree root and rim of a steam turbine blade with complex damping structure was conducted by three-dimensional contact finite element method and mathematical optimization algorithm. A multi-variable parametric model of three turbine blades and rims with fir-tree root and rim was established. Twelve critical geometrical variables of the root-rim were optimized to minimize the maximum equivalent stress of the root-rim. The optimal structure of the fir-tree root-rim was finally obtained through the optimization process and the equivalent stress of the root and rim both had evident reductions, Compared with the initial structure, the maximum equivalent stress of the root and rim reduced by 13.47% and 12.26%, respectively. Relevant work is expected to support the design of turbine blade root-rim in theory and improve the operation reliability of turbo-machinery to some extent.

Graphene is one of the most promising new electrochemical materials for lithium-ion batteries (LIBs) because of its superior electronic properties. In this work, we describe the patent map on graphene-based LIBs. We discuss the time-line for the amount of patent applications on LIBs, the nation and applicant distribution of the patent applications. We analysis the technology distribution in this field, which shows that applications about graphene-based cathode increase really fast. According to the analyse result, the Chinese patents have occupied the leading position in this new field but the applications are mostly submitted by colleges and research institutes, which suggests that few inventions have been implemented. In order to hold the market trends and improve competitiveness, it is necessary to keep eyes on worldwide patent application situations and build effective patent strategy, therefore, we also raise some advices and countermeasures about the graphene-based LIBs.

This paper suggest 5m depth line is suitable depth for sea areas reclamation based on study of sea areas reclamation investing and established estimationmethods for spatial resource capacity of sea areas reclamation. Then Liaoning province in China was chose as a case to estimateitssea areas reclamation capacity. The result shown as follows: Depth of sea areas near the coastline in Liaoning province is smaller than 5m in most sea fields. Length of coast with under water slope angle less than 1°is 1988.77km and account for 52.25% coast of Liaoning province. The total areas of sea reclamation capacity is 211714.06hm2.Its distributes mainly in Dalian sea areas, Jinzhou sea areas and Yingkou sea areas with percentage of 47.19%，18.78% and 14.53%,respectively.

A rig was built to study the friction damping characteristics of metallic materials with non-conforming contact. The hysteresis curves which show the relationship between the tangential force and relative displacement of the contact between a spherical surface and a flat surface were measured. The effects of the vibration amplitude on the friction damping characteristics of the contact were investigated. The results show that both the amplitude of friction force and the friction coefficient increase as the vibration amplitude increases at first and then reach to a constant value. The equivalent stiffness decreases as the vibration amplitude increases, while the equivalent damping increases at first and then decreases slowly. And both of them trend to constants when the vibration amplitude is larger than 4.8μm.

As the main bearing part in a turbine blade, the root carries most of the loads of the whole blade. The improvement of the root structure can be used to enhance the operation reliability of steam turbine. The research on design optimization for double-T root and rim of a turbine blade was conducted by three-dimensional finite element method. Based on the APDL (ANSYS parametric design language), a multi-variable parametric model of the double-T root and rim was established. Twelve characteristic geometrical variables of the root-rim were optimized to minimize the maximum equivalent stress. The optimal structure of the double-T root-rim is obtained through the optimization. Compared with the original structure, the equivalent stress level of the root and rim has a significant reduction. Specifically, the maximum equivalent stress of root and rim reduces by 14.25% and 13.59%, respectively.

Digital CR of head and neck overcomes the disadvantage of regular X-ray radiography, which can not reveal bone and soft tissue position deficiency in one exposing, and reduces the X-ray radiation dose. Meanwhile, various factors cause the decline of image quality, and images must be enhanced in order to meet demands of doctor's clinical diagnosis. The general enhancement algorithms don’t consider body's structure differences and density characteristics. A new adaptive CR enhancement algorithm was proposed in this article, and head and neck CR images were processed with this method and compared with linear unsharp masking method. The experiment proves that the details of CR image enhanced were abundant and enhanced CR image had good visual effect, SNR was high, as well as detail variance /background variance (DV/BV) indicating that this algorithm is suitable for head and neck CR medical images

Aiming at building a Lidar data interpolation model, this paper designs and implements a GA-BP interpolation method. The proposed method uses genetic method to optimize BP neural network, which greatly improves the calculation accuracy and convergence rate of BP neural network. Experimental results show that the proposed method has a higher interpolation accuracy compared with BP neural network as well as linear interpolation method.

Digital CR medicine radiation image is in doctor’s favor and has became medicine imaging technology new hot spot because of its high gray contrast、powerful computer disposal function、little radiation dosage、non-film diagnosis、different area consultation. But degradation of digital X-ray medical image such as low contrast and blurring during radiographic imaging, caused by complexity of body tissue and effects of X-ray scattering and electrical noise etc., can worsen the results of analysis and diagnosis. So it is usually needed that CR medicine image is enhanced to improve its vision quality, and easy to doctor’s more accurate diagnosis. The general enhancement algorithms over enhancing the contrast and lose image details, aiming at the defects, an enhancement algorithm for CR image is proposed based on the ratio of deviation to mean of domain. The arithmetic enhance CR image edge details by adjusting factor K based on the ratio of deviation to mean of domain of CR image. Experiment results demonstrate that the algorithm enhances CR image detail and CR image enhanced has good visual effect, the adaptive enhancement method is fit for CR medicine image.

the moisture distribution in untreated and esterified poplar with Maleic anhydride was studied in the present paper employed nuclear magnetic resonance (NMR). The results show that relaxation times decrease with the the fall of moisture content, and there is a linear equation between the moisture content and transverse relaxation time in esterified wood. The content of bonding water and free water in the esterified wood decreased simultaneously during the drying.

As a kind of crude and green material, wood is essential to human life. Meanwhile, the amount of water played a vital role to almost all engineering properties of wood. Moisture affects dimensional stability, physical and mechanical properties, and susceptibility toward biological degradation. Consequently, it provides a theoretical basis for the reasonable drying model to explore the water assignment and content in timber. we present here the application of a nuclear magnetic resonance technique, which is used to quantitatively analyse water distribution in wood on the basis of T2. In this paper, we will analyse the water distribution in hardwood on the basis of T2. Refer to the scanning electron micrographs of the hardwood, we can speculate the relaxation time of the water in different cell lumens respectively. Moreover, it is even more important to calculate the organic proportion in wood by the corresponding amplitude of signal derived from the water in different cell lumens. This, compared with a scanning electron micrograph, has allowed us to produce a assumable distribution of water in wood, even the corresponding organic proportion in wood, which allows us to speculate physical and mechanical properties of wood. A mobile NMR probe has been used as a non-destructive and non-invasive tool for water content analysis on wood samples. In this paper, we will adopt NMR methods to explain. This, has opened up a way for the accurate determination of the moisture content of wood, even can be applied to the areas of food and so on. Keywords: Nuclear magnetic resonance; Water distribution in wood; T2; Scanning electron micrograph; Water content

Avalanche transistor is a ideal device which can provide quick response and high peak power simultaneously, and this device is cheap. A pulse generator based on avalanche transistor is designed in this paper; this generator can generate transient current pulse. This generator can be easily triggered, what is more, the performance of this generator is stable and it has a well-behaved load capacity. Therefore, this generator is suitable for using as the magneto-optical switch in the all-optical communication network. Future work will focus on further shorten the duration and rising time of the pulse.

Two-step for wood esterification with oxalic acid and cetyl alcohol is developed in this study. The esterified wood powder was investigated by Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The results show that ester groups substituted parts of the original alcoholic hydroxyl groups, and crystallization occurred during the modification. In addition, surface wettability, moisture adsorption and water absorption tests for wood specimen have showed that the modification improves the moisture and water resistance.

Seeing that there are some unsafe factors in the process of ATM using,an ATM automatic identification system with extend functions was developed. As human face features are unique, face detection is added to the ATM as a method of authentication. Since face detection is a primary link of face recognition, our system adopts AdaBoost algorithm which is based on face detection. Experiment results demonstrated that the computing time of face detection using this algorithm is about 70ms, and the single and multiple human faces can be effectively measured under well environment, which meets the demand of the system.

Biometric identification technology deals with the identification of individuals based on their biological or human behavioral characteristics. Biometric identification method is reliable, anti-counterfeit, convenient and safe. At present there are some insecurity factors in the ATM (automatic teller machine) in bank system. Methods such as combining biological recognition with the ATM machine, adding the face recognition technology, fingerprint recognition, second generation ID card recognition, enhancing automatic identification are developed to improve the security of ATM.