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We demonstrate a novel design of large-size device in AlGaN/GaN high-electron-mobility transistor (HEMT). Depletion mode (D-mode) HEMTs and enhancement mode (E-mode) HEMTs are fabricated in our research. The saturation current of D-mode HEMTs is over 6A. By using Cascode structure, the D-mode HEMT becomes a normally-off device efficiently, and the threshold voltage of it rises from-7V to 2V. By using BCB (Benzocyclobutene) as the passivation, the E-mode HEMT shows an excellent characteristic. Also, when the VGS of the E-mode HEMT is over 9V, it still shows a good performance.

Owing to the growing gap of natural gas between supply and demand in China, the unconventional natural gas, including coal-bed methane (CBM) and shale gas, has been considered as strategic energy sources. An assessment by China’s Ministry of Land and Resources (MLR) announced that China has potentially resources of 36.7 trillion cubic meters of CBM and 25 trillion cubic meters of shale gas, larger than those of the U.S. Controversial views about their commercial prospects and priorities in order are available. This research aims at exploring which is more economically viable and worth the priority. A cost-benefit analysis (CBA) based on average single well data is employed to carry out a comparative analysis between two typical fields, the coal-bed methane (CBM) fields in the Qinshui basin and the shale gas fields in Sichuan basin. The net present value (NPV), the internal rate of return (IRR) and the payback period are used as indicators in this analysis. The results indicate that CBM is superior to shale gas in viability under the current technological and economic conditions, and the future of the CBM industry is clearer than that of the shale gas industry, but the latter is still promising if the drilling costs can be reduced significantly with technical progress. We suggest that the CBM industry should be given the priority to, and the policy for shale gas should focus on promoting technical innovations.

Currently, the research of marine dual fuel engine is rare, while the combustion process of marine dual fuel engine is no precise conclusion. This paper built a combustion model of dual fuel engine by AVL FIRE software, and compared experimental data to prove the accuracy of the model, analyzed the characteristics in combustion process of marine dual fuel engines, provided a theoretical basis for the further optimize and design of marine dual fuel engine.

For the pulse wave signal acquired by the pulse analyzer, it’s necessary to remove the large number of noise signal by noise reduction processing. For signal noising processing using wavelet transform method in the time domain and frequency domain and the signals can characterize the ability of local information, and it is self-adaptive. Determine the main wave peak and trough points based on extreme value method and pulse wave periodicity, using the threshold method to determine the dicrotic wave starting point and dicrotic wave peaks, we also use the MATLAB programming to implement the algorithm.

Compared with traditional screw pump,all-metal screw pump have more advantages in the oil extraction. In this paper, all-metal single screw pump's geometric model was made by PROE software; then the dynamic mesh technique was applied to mesh the model and constraint condition was applied in the ANSYS-FLUENT software. 3D flow field was numerical analyzed In that software, the impacts of screw speed on volume flow and volumetric efficiency were concluded, the conclusion can offer some valuable guidances to the all-metal single screw pump's design.

To deal with the complicated spiral surface of screw pump,this article uses Pro/E to build geometry model.And it improves the method of the grid topology to use the dynamic grid ideas.At the same time,using the method of Computational Fluid Dynamics to numerical simulation for full-metal single screw pump,analysis and study that viscosity affect leakage properties,the torque of surface of rotor and the volumetric efficiency.

A high-performance bandgap reference voltage source design method is proposed in this paper, according to the shortcomings of traditional bandgap reference voltage source. This method combined CSMC 0.35μm CMOS process with Aether software technology, enabling to improve the bandgap reference source op amp performance and take into account accuracy and stability of the system. From the experimental results: this bandgap reference voltage source output voltage has changed about 63 mV when the temperature varied from to , and the line regulator is 0.4mV/V when the power supply voltage varied from 3.2V to 3.3V. This system has advantages of high accuracy and good stability.

In this paper, the multi-body dynamics software EXCITE was used to simulate the connecting rod big end bearing of two-stroke marine diesel engine. The result showed the stress analysis of connecting rod big end bearing. The purpose is to provide a theoretical basis for the actual conditions of connecting rod big end bearing, and to improve the design of the crankshaft structure.

Hospital network office automation system could make the hospital connected by a PC, terminal equipment, medical equipment and hospital networks to link up and connected to the Internet. In this paper, the star tree on the hospital's existing network structure transformation, using port aggregation technology upgrades to existing network data transmission and improve the operating efficiency of the entire hospital network, and the hospital server, computer workstation security configuration and remote management configuration, database and application development of all types of information systems are a good network support.

Based on the analysis of E-government decision support system's basic theory and mainstream solutions, combined with the popular OLAP technology, presents a white spoon OLAP based decision support system to improve e-government program, using data warehouse and model library together to support OLAP analysis, test cases and successfully used with the project, the results show that this scheme can achieve the desired requirements, with better performance and fast response performance multidimensional analysis, OLAP operations can be completed with reference promotional value.

Bedsore is a common disease for long-term bedridden patients,electronic treatment instruments can effectively prevent the occurrence of bedsore.In this paper,stress sensor and micro-controller are used to sample pressure signal of each part of the body and send the signal to PC by RS232.LabVIEW virtual instrument is designed to analyze the measure pressure data,and estimate the state of every parts of the human body that have been continuously pressed.Then the LabVIEW instrument will send control signals to the corresponding pumps of the mattress.This instrument can prevent human skins being pressed too long in part areas.

The face of the valve seat sealing surface design, the finite element analysis and calculation of ball valve seat sealing surface and angle of the design method is studied. Through 3D CAD technology for ball valve design, guide 3D design model to finite element analysis software to calculate ,reveal the sealing load distribution of pressure in the valve seat sealing surface, sealing pressure values are obtained, through the valve seat sealing surface design Angle analysis, to obtain the optimal value of sealing surface angle.

According to the characteristics of non-linear, time-varying and large time delay in the control of grate cooler, a multi-mode intelligent control method is proposed in the paper.The multi-mode intelligent controller is builded up by variable integral PID control, fuzzy control, Bang-Bang control and expert control. This control method through a multi-mode intelligent control rules automatically identifies different modal and chooses a corresponding control algorithm to correct variable integral PID control.Industrial applications show that the control system has good robustness, achieved good control effect.

This paper present a typical respiratory movement method simulated by LabVIEW and Simulink.Because calling Matlab in LabVIEW can control hardware easily and realize complex algorithm concurrently,so we combine the capabilities of Simulink and Real-Time Workshop with LabVIEW,and use Simulation Interface Toolkit importing simulation models into LabVIEW.This paper provides a through introduction for respiratory modelling and control design,the combined method that can integrate the advantage of the two method is illustrated for control aim.

A novel low-noise amplifier (LNA) suitable for COMPASS receiver applications is designed in SiGe-BiCMOS technology. Inductively degenerated technique and resistive feedback technique are employed to reduce the noise figure. With 1.8V power supply, the measured results achieve 17.23dB power gain and 2.58dB noise figure at 1.561GHz.

Aiming at the vibration characteristics of cylindrical shell, the different cases of cylindrical shell are analyzed through FEM, and the cases are determined according to the circular angle. The free modality results show that with the same dimension of shell, the modal shape of cases are similar to each other, the frequency increased with the increase of circular angle, but for circular angle (say 90°), the increase trend becomes lower as the frequency difference ratio is lower. In excited vibration analysis, there is a relationship between acceleration peak value and circular angle, which is illustrated by a non-dimension parameter.

The mass flat raft foundation Section is large and Cement is in large quantities, the temperature changes in the larger cement hydration heat of the water releasing, the temperature stress is main reason reducing cracking. According to the basement of a project of Guangzhou large slab raft foundation engineering as an example, Discussing the construction technology measures of early crack of large volume concrete of raft plate in the process of construction,. The results show that it Can effectively prevents the slab foundation structure cracking and achieves good results through controlling Concrete materials and concrete temperature Parameter such as the lifting machine temperature and the pouring temperature and the expansion joint or the whole pouring length.

The micro-vibration mechanism and fault characteristics of micro-gears was described and the faults were classified with no fault, gear crack, gear face wear, tooth face attrition, tooth face crack. The wavelet neural network was proposed and optimized with differential evolution algorithm. The test was taken with the diagnosis information acquired with vibration experiment and designed as training samples which was normalized for wavelet neural networks, the simulation was taken under MATLAB and the simulation result shows the new algorithm with convergence quality and higher diagnosis precision.

Based on Roller Straightening Theory and Elastic-Plastic Beam Research, A Appropriate Mathematical Model of Straightening has Set up.The Author Regards the Tube as a Continuous Bending Beam and Discuss in Detail the Relationship between the Straightening Force and the Bending Moment. Calculating the Amount of Deflection for Tube. in this way ,it Provided a Scientific Basis for the Copper-Clad Steel Tube Straightening Parameter Set and Engineering Application.

Kinematic models, which contain flapping and deformations, of a bat flapping wing when it flies at medium speeds are presented in the study. The deformations include cambering - morphing in the chordwise direction, bending - morphing in the spanwise direction and twisting respecting angles of attack (AOA) varying along the length of the wing. In the study, we assumed a circular-arc-shaped deformation when cambering or bending occurs, and introduced controlling parameters for each morphing. Then we showed the expressions of the controlling parameters varying with time at the bat flight speed of 3m/s according to the data provided by a literature, and verified the reasonability of the assumptions at last.

Our research group has invented a kind of new technology called coaxial inside-beam powder feeding. By series of experiments, this paper analyzed and summarized the process parameters’ influence on the cladding layers’ feature and quanlity, which contain the laser power P, the powder feeding speed Vf, the scanning speed Vs and the defocusing distance L. Some cladding experiments also were made to aquire the cladding roads with variable width. The experimental results indicate that when P, Vf and D×Vs are fixed, roads with stable height and uniformly changing width are acquired by changing Vs and L at the same time.

The article firstly puts forward an experiment scheme for the study according to the laser rapid prototyping of high-level revolved body accumulate based on inside-laser coaxial powder feeding. And the changes of Z-axis feeding and power regulation in the progress are observed by high speed CCD technology. Then the organization and performance of laser cladding rapid prototyping parts are analyzed. The study shows that the microstructure of the parts is fine and has the characteristics of directional solidification and rapid solidification. The hardness of the parts is better than that of the castings and the ordinary steel parts after heat treatment. The hardness of cladding layers is floated , but there are little differences between each layer.

The similitude requirement of excited load was deduced to maintain the consistent vibration between scaled model and prototype structure, based on the modal theory of multi-DOFs systems. The similitude of load frequency was another demand to maintain the consistent vibration, with the similitude of structure size and load magnitude. The dynamic similitude problem of a liquid tank was studied by finite element method and test analysis respectively. The results show that the similitude of load frequency is the insurance for the consistency of prototype and scaled model structures vibration. In a case the magnitude error of displacement is 8% to 10%, and the displacement and acceleration have all changed distinctly without the similitude of load frequency. All the results indicate that the similitude of load frequency is the key factor to analyze the scaled model dynamics correctly.

For the sake of evaluating the content of mineral oil and in water, and further more we can judge water quality pollution, we finally develop an infrared spectrometer based on STM32 which is on the basis of infrared spectrophotometry. The instrument realizes calculating the absorbance and concentration automatically with the help of high-precision pyroelectric infrared sensor and signal processing circuit. Besides it combines with built-in A/D converter and USB data transmission module, it can draw the standard curve on the host computer. Experiment results show that the instrument is accuracy enough and simple enough to use.

In a wireless mesh network, the need for cooperation among wireless nodes to relay each others packets exposes the network to a wide range of security threats. A particularly devastating type of threats is the so-called wormhole attacks. In order to defense against the attack, a type of wormhole attack model and a watch nodes-based wormhole attack detection scheme were presented in this paper. The scheme that is based on the combination of a number of techniques, such as distributed voting, watch nodes based detection and identity-based cryptosystem. Qualitative analysis and simulation show that the wormhole attack detection scheme is more advantageous over the some of the previous schemes in terms of performance and cost.

To improve the output performance of piezoelectric linear motors, researches was carried on the vibration characteristic for the stator of dynamic-friction type non-resonant linear piezoelectric motors. By analyzing the construction and working mechanism of the motor, longitudinal vibration model was established for the stator of motor. Then the vibration differential equation of the drive tip was deduced and longitudinal displacement functions were proposed. Further, the prototype was fabricated and investigated by experiments on the longitudinal displacement of drive tip under different excitation conditions. Experiment results proved the vibration characteristic theory of stator that the longitudinal amplitude of drive tip increases with excitation voltage. The maximum amplitude of drive tip is 0.85μm and the output force is 3 N on condition that the operation voltage is 90 V and the frequency is 1.6 kHz. The above studies can provide theoretical basis for performance optimization of motor and for structural optimization of stator.

A fully integrated low noise amplifier (LNA) for wireless local area network (WLAN) application is presents. The circuit is fabricated in 0.18μm SiGe BiCMOS technology. For the low noise figure, a feedback path is introduced into the traditional inductively degenerated common emitter cascade LNA, which decreases the inductance for input impedance matching, therefore reduces the thermal noise caused by loss resistor. Impedance matching and noise matching are achieved at the same time. Measured results show that the resonance point of the output resonance network shifts from 2.4GHz to 2.8GHz, due to the parasitic effects at the output. At the frequency of 2.8GHz, the LNA achieves 2.2dB noise figure, 19.4dB power gain. The core circuit consumes only 13mW from a 1.8V supply and occupies less than 0.5mm2.

As the rapid development of urbanization in China, the conservation of building energy has become a world trend, the rapid rise of building energy will lead a huge pressure on energy supply and environment protection. Renewable energy sources, like solar and geothermal energy, have the incomparable superiority than conventional energy sources, if renewable energy sources could replace conventional energy source and play a major role fully, the serious energy consumption must be relieved effectively. In this thesis, the summer-refrigeration of SWHP (Surface Water Heat Pump) is set as the research target, the applicability research of SWHP is carried out, apart from that, building the evaluation system and putting forward the level determination method of energy efficiency.

To manufacture three-dimensional textile composite preform using method of unilateral suture technique, a unilateral suture manipulator system has been designed. In order to inspect whether it can meet the design requirements , this article establish the kinematic model of the major institutions by using vector method,and use simulation software to analysis the kinematics of thread-leading, thread-hooking and thead-taking-up mechanism. Accordingly, law of motion graphs of the mechanism can be reflected, and the simulation results demonstrate the design of unilateral suture manipulator which are reasonable and efficient.

In recent years, Chinese Government adopts series of policies and actions to advance the building application of the renewable energy resources. Based on the policies for demonstration projects of application of renewable energy sources to buildings (ARESB) in China, this article discusses the policy systems for the demonstration projects in all aspects, including application and review systems, supervision and administration systems, inspection and assessment systems, and the whole policy systems are based on promoting the advance techniques, practicalities, reasonable economy, demonstration and generalization meaning of ARESB. Based on the actual construction and operation of the demonstration projects, the article also analyzes and evaluates the implementation effects and suitability in different areas concerning each technical type, and then analyzes and evaluates issues existing in the implementation of the policies for the demonstration projects of ARESB, with further policy suggestions provided.

This paper first studied the feasibility in application and advantages of the the full metal single screw pump by the method of theoretical research . Then the paper deducted the motion characteristics of the rotor around the stator and flow rate of the metal single screw pump .It is pointed that the center of the rotor profile is always located in the long shaft of the section of stator in any section .As the rotor rotates, the center of the rotor profile on this section takes straight reciprocating motion along the long axis of stator section .The results indicate that it exists feasibility in the designing and processing of full metal single screw pump. Thereby it provides theoretical basis for the application of full metal screw pump.

The development of parametric calculation module program based on APDL, the completion of 3D acoustic modeling of a ship floating cabin, the selection of constraints according to the actual work situations, the finite element modal analysis of the overall cabin in the ANSYS environment and comparative analysis of a low-order vibration frequency of the cabin under different fire ratings. Acoustic calculation program of the fluid-structure interaction is used to analyze harmonic sound field and verify the impact of different thickness fireproof rockwools on the cabin acoustic performance. Parametric Design and Finite Element Analysis are combined to achieve the adjustment of the structural parameters of the complex models, automatically generate solid models and complete finite element analysis, which is important for the optimization of the acoustic design of the ship cabins.

In acoustic emission (AE) testing for steel structures, location of AE source is an important problem because the source is often related to micro-structure change or defects. In the paper, an activity detector was proposed to locate AE sources based on clustering analysis and AE statistical parameters. Firstly, a location plane, which may contain AE sources, was obtained by the technique of time difference of arrival (TDOA). And the plane was divided into some sub-planes base on clustering analysis. Then, the activity detector was established based on two AE statistical parameters of energy counts and ring-down counts. Finally, the detector value in each sub-plane was calculated and the sub-plane with the maximum value was identified the position of AE sources. Further, by applying the method to test crack sources in a steel structure experiment, the crack position was located correctly compared with actual crack sources. The results demonstrated that the method based on the AE activity detector can reduce ambiguity and locate AE sources accurately and effectively.

As disinfection by-products, the taste and odor (T&O) compounds were produced by chlorination at the end of water treatment. The existence of T&O compounds causes the pipe water with unpleasant odor and reducing water quality. Based on the latest research achievements at home and abroad, the characteristics and formation mechanisms of typical T&O compounds produced by chlorination are introduced. The new analytical method of electronic nose is also expounded. In addition, the common control technologies, such as pre-oxidation, activated carbon adsorption and bio-membrane, are reviewed. Since the precursors of T&O compounds shows small molecular, stable structure and low concentration, some coupling technologies including ozone-GAC, permanganate-PAC, and bio-membrane and GAC treatments, are employed effectively.Key words: chlorination; odor and taste compounds; disinfection by-products; precursor; electronic nose

The experiment was carried out to measure the effect of membrane treatment on the kinetics of chlorine decay in PE pipes in the water distribution systems. The results revealed that water had the potential to form halomethane compounds with chloroform being the most dominant. The formation of THMs is no longer relatively exponential relationship with the reaction time, but also decided by complex elements, including DOC, pH, conductivity, flow rate, and several other indexes. Since Chloroform (CHCl3) has the maximum concentration of the four THMs, clear understanding of its causes, pathway and mechanism will help to regulate and solve the THMs problem.

This paper describes a comparison case study devised to quantify the effect of spindle on dynamic performance and surface quality of a vertical machine center. Measurements are performed to evaluate the: (1) spindle thermal growth using infrared temperature measurement instrument; (2) idling vibration of the spindle at different speeds using the laser interferometer; (3) transfer dynamic stiffness of the spindle using LMS; (4) machining surface quality using surface roughometer. The integrated effect of the spindle assembly process on the above performances has been identified. A detailed comparative analysis of the surface quality showed that the accuracy loss of the vibration induced by the machining force and the unbalance of the spindle system is dominant for the machine tool selected for this study.

The electrical non-fiberoptic endoscope (ENFE) is primarily designed with no optical fiber. The illumination of a ENFE is important due to it affects the image quality of endoscope and the results of surgery. A investigations of the illumination of a ENFE are proposed in this paper. The illumination of ENFE is important due to it affects the image quality of endoscope and the results of surgery. The illuminations of orange-red inside were higher than the black inside. The illumination of rigid rod lens is 500 lux at 5 cm. The illuminations of ENFEs were decrease to 200 lux rapidly at 3 cm in case 4 although the illumination was over 1500 lux at first.

Frequency dependence on image reconstruction for a buried conducting cylinder is investigated. A conducting cylinder of unknown shape scatters the incident wave in free space and measured the scattered field. By using measured fields, the imaging problem is reformulated into an optimization problem and solved by the steady-state genetic algorithm (SSGA). Numerical results show that the reconstruction is quite well in the resonant frequency range. This work provides both comparative and quantitative information

The light reflectivity of multiwall carbon nanotubes (MWCNTs) in the 1150nm - 1755 nm wavelength range with pattern-less and pattern-grown nanotubes are studied. From test measurements it concludes that when the multiwall carbon nanotubes are pattern-grown fabricated its return loss is linearly proportional to the nanotubes grown height and consequently the pattern-grown CNTs can be implemented as a good optical attenuator. However for high density nanotubes fabricated with pattern-less process it has greater than 45 dB return loss, this is equivalent to have less than 0.56% reflectivity; with this high absorption effect it can be utilized as a black body absorber.

In this paper the process of implementing a low dropout regulator (LDO) chip is presented; it is using uses Taiwan Semiconductor TSMC’s Manufacture Inc. 0.35um 2P4M process. The circuit designed with the described process can be is operated at 3-5V input voltage to generate 2.5V output voltage. Maximum output current can be running up to 200mA. This LDO is implemented without placing output capacitors to reduce BOM (Bill of Material) cost and stable between 0~200mA loading current and the chip is stable when the loading current is in the range 0~200mA. [8] The new proposed LDO chip can be implemented in the handheld mobile devices, battery powered equipment, wireless devices, cordless phones, or PC peripherals.

A method which can be used to analyze and separate the vibration signals of diesel engine is proposed. The vibration signals contain a great deal of information about the engine’s fault state, and it is hard to obtain the fault characteristic parameters because of the complex mechanical movement and operating conditions. Study on vibration by fourth order blind identification is carried out in this paper. And FOBI model that estimate the separation matrix by independent component analysis is established and applied to diesel engine vibration to separate the different signals. The results show that signals of different characteristics can be separated perfectly. This method can be used as the pre-processing step to obtain the fault characteristic parameters.

To investigate the realistic spiral motion of a spinning guided projectile, a novel analysis method based on flight data is proposed and further applied. A mathematical model of spiral motion is derived in body coordinate system firstly, and the procedures of the novel method are then described in detail. The spiral motion can be induced by non-zero velocity and rotation rate along the longitudinal axis with at least one non-zero velocity and rotation rate along transverse axes. In the case of non-zero velocities and rotation rates exerted along triple axes, it is observed that the spiral motion consists of single circular motion and double circular motion, and the spiral motion depends on both spinning rate and attitude angles of flight trajectory.

Principle of the pipeline leak detection system is presented, and the leak detection method based on acoustic wave and wavelet analysis is studied in this paper. The dynamic pressure transmitter based on piezoelectric dynamic pressure transducer is designed. The characteristic of dynamic pressure transmitter when pipeline leak happened is analyzed. The dynamic pressure signal is suitable for pipeline leak detection for quick-change of pipeline internal pressure, while the static pressure is suitable for slow-change of pipeline internal pressure. The signal is analyzed by wavelet analysis method to detect the singularity, and the singularity is used to recognize and locate the leak. This paper indicated that the dynamic pressure signal could be adjust to this detection that the pressure changes in the pipeline. Field tests in 68.2 km pipeline segment show that the method detects pipeline leak rapidly and precisely.

The UFD method was used to analyze the flow field in the swirl atomizer whose geometric structure had been designed with ideal theory algorithm. RNG (Renormalization Group) k-turbulent model was applied to the numerical simulation of the flow field, and SIMPLE algorithm was used to solve the finite difference equations. Through the analysis of pressure and velocity fields get by the numerical simulation, we found that the use of CFD method in the swirl atomizer design is beneficial for getting more detailed and accurate flow structure and advantageous to analyze the influence of different nozzle geometry, and then given a reasonable design opinion.

Transcutaneous energy transmission (TET) systems are designed to deliver power from an in vitro primary power source to in vivo implantable secondary over relatively large air gaps via magnetic coupling. This paper proposes an optimization method with given output power to meet different practical application. The transmission efficiency is the objective function; primary and secondary coils are design variables; constraints are based on bifurcation phenomenon and components peak over-voltage and peak withstand current. We have used MATLAB/ SIMULINK to verify the analytical results.

An increasing trend towards the demand for resisting to Freeze/thaw exposure has led to fibers being incorporated into concrete. This paper addresses the freeze/thaw durability of carbon fiber reinforced concrete by using a paired comparison test based upon relative dynamic elastic modulus and the rate of loss mass. The carbon fiber reinforced concrete was found to be more durable than plain concrete probably due to the high elastic modulus of carbon fiber. Durability is an important material property and carbon fiber reinforced concrete needs to be widely tested to gain confidence for use within the industry and this work shows future possibilities.

This paper analyze ultimate bearing capacity, transfer mechanism, failure process and influence of aperture, steel bar diameter, concrete rating and on elastic bearing capacity and ultimate bearing capacity of PBL shear connectors by the finite element analysis software ANSYS. This paper can provide a reference for further design of PBL shear connectors as well as push-out or pull-out test. The results show that the elasticity bearing capacity of PBL shear connectors is determined primarily by concrete while the ultimate bearing capacity is determined primarily by perforative steel bar.

According to the example of using a common grinding and composition of parts processing movement and achievement elements, the design of construction of special NC technologies in ordinary grinding machine was formulated. . The grinding and polish-grinding were performed by using two NC systems in series to achieve multi-axis movement. The function and application scope of NC technology were expanded because the instantaneous compensation of the grinding wheel and the polish-grinding wheel were performed under a rectangular coordinate system and a polar coordinate system by using an open loop NC system. The application of surface recovery of grinding wheel by NC reconstruction and extension applications of processing the track of involute curve were referred.