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Laser surface modification technology is one of the most advanced technologies, which uses laser to modify the characteristics of the surface to offer superior performance for various industrial applications. In this study, laser surface hardening behavior of GM246 case iron was investigated. Result shows that excellent laser surface hardening of GM246 cast iron need low power density and scanning speed. With power of 2500 W, scanning speed of 300 mm/min and power density of 2500 W/cm2, the laser surface hardening of GM246 cast iron achieved the hardness of 790HV, which was 2-3 times higher than the hardness of base metal. Also, the depth of laser surface hardening case achieved 0.9 mm and the hardening case demonstrated three subzones.

Interatomic potential plays an important role in molecular dynamics simulation, which determines both the efficiency and accuracy of the simulations. Lattice inversion is a method which can be used to develop interatomic potential from first principle results directly. In present work, a robust potential model based on lattice inversion is proposed. Then the potential model is applied to develop interatomic potentials for eight common FCC metals. The cohesive energy curves calculated using first principle calculations can be well reproduced, which verifies the reliability of the developed potential. Additional physical properties, including equilibrium lattice constant and cohesive energy, elastic constants, are predicted and found reasonable agreement with corresponding first principle results.

For studied the rule of wind turbine output characteristic in condition of variable wind. The paper set up a wind model for a wind farm and a simulation model of 1.5MW wind turbine. Choose two control tactics which called voltage control and reactive power control to do the simulation and test. The result shows that took reactive power control at normal operation, the turbine get a well performance. If fault happened, choose voltage control was reasonable. So it provide reference for turbine operation.

It’s difficult to describe the 3d geometry and to establish the 3d model of tower equipment in OpenGL. High-level command functions to define complex three-dimensional modeling is not provided in OpenGL. This paper introduces 3d model of the tower equipment how to display dynamically in OpenGL. Interface of OpenGL import 3d model is description in detailed. Storaging format and reading file of STL (Stereo Lithography) are elaborated. How to build the 3d model is descripted. When tower equipment displayed dynamically, what is the key step to establish the model of tower equipment. The dynamic model of the whole tower equipment is displayed, in order to see clearly the structure of tower equipment.

Elliptical head is an important standard part of the separation tower equipment. It can not be generated by tensile method, rotation method, because the rotation axis can not pass region. This paper introduces the ObjectARX programming environment. It describes how to build the menu and the dialog box. ObjectARX is a secondary development tool of AutoCAD. With its function and its mechanical drawing once learned, four arcs of ellipse can be used to build 3d modeling of head.of tower equipment. The ObjectARX programming technology is applied to develop AutoCAD, making it more convenient to darw the professional 3d graphics.

This paper introduces the basic principle of phase code pulse compression technology, the characteristics of phase coded pulse compression system, and the technical approach of radar to implement phase code pulse compression.

Herein, a novel fuzzy PID temperature control system was proposed based on the technological process and control requirement of the crystal annealing furnace. Simultaneously, the electric control system was also designed with SIEMENS S7-300 PLC as the master controller. The results indicated that the system has the merit of rapid response time, low temperature fluctuation and all of the test items could meet the requirement of the actual utilization.

The microstructure and mechanical properties of Mg-6Al-1Zn-0.9Y-1.8Gd alloy have been studied by micro-analysis and tensile tests. The results showed that the alloy mainly consists of Mg matrix, Al2Y, Mg17Al12and Al2Gd. The best tensile strength of the alloy was 255 Mpa at room temperature, and the alloy still had the very high mechanical property at high temperature.

In this paper, a novel cooperation space-time network coding (CSTNC) scheme based on multi-sources distributed cooperative network is considered. In this scheme, multiple sources transmit signals to relay and destination node. The relay re-encodes the decoded signals through space-time network coding with the aid of multiple antennas. The simulation shows that the BER, capacity and outage probability of the CSTNC becomes better with the increasing of relay antenna number and very close to traditional space-time network coding (TCSTC) scheme. Meanwhile, transmission efficiency analysis demonstrates that CSTNC scheme has higher transmission rate.

In order to deal with subway emergency, the paper builds the emergency drill system based on scenario analysis for the security of persons and property within the subway. By participating in the drill system, make sure that units and division involved in the rescue and command system learn their responsibilities by heart under emergency, enhancing collaboration of various departments, improving the efficiency of emergency rescue, thus the rescue can be conducted orderly. This paper introduces the concept of subway emergency, emergency management and organization and the drill system.

This paper presents an algorithm about key management including key generation and key recovery in cryptosystem based on fingerprint and fuzzy decision. Traditional key for the encryption and decryption is remembered by a trusted person, or stored in a safety location. The key may be lost or misused for the person’s self-ish desire. Sharing secret algorithm is used to prevent from misusing in a single management, and fuzzy vault scheme is used to avoid the disadvantage of numerical password. But the proposed method is not an easy combination of fuzzy vault and sharing secret. To keep from the collusion among some persons, a simple fuzzy decision is added in the proposed method. Security analysis and experimental results are given to show the proposed algorithm is feasible and safe for key management in cryptosystem.

Subway train positioning technology is one of the key technologies, however when red band appears in dispatch center, train ground communication fails and other issues, you need a back-up emergency systems to provide train position information for the station dispatchers in order to arrange train route. This paper describes a back-up system for positioning subway trains. The system is a combination of vehicle and ground subway train assisted positioning system, it can fast and accurate get the location information of subway trains, to provide protection of safe and efficient operation for the subway trains.

The influence of the solution treatment (at the temperature of 500-520°C for 4-12 h) on microstructures and mechanical properties of Mg-Gd-Y-Zr alloy was investigated by means of optical microscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and Vickers hardness measurement. The as-cast alloy contains a microstructure consisting of α-Mg matrix, Mg5Gd phase and Mg24Y5phase. With increasing solution temperature and time, the quantity of the primary particles (Mg5Gd and Mg24Y5) in the alloy continually decreased, and the degree of recrystallization gradually increased, which result in the gradual decrease of the Vickers hardness of the solution-treated alloys.

Through the relations among the torpedo velocity at tube outlet, cylinder volume, cylinder pressure and emission valve size, we adopt the projection pursuit regression method and establish the model to predict the torpedo velocity at tube outlet. Through the comparison of experiment data and model prediction, fitting accuracy of this relation model is stronger and the projection pursuit regression is an efficient method which can research the initial ballistic trajectory of ship-launched torpedoes.

In the computer vision, feature extraction is an important research orientation. Corner and edge detection is a basic technique for obtaining local feature in this image. In the paper, we propose a method that corner and edge of image is detected simultaneously by an annealed chaotic competitive network. The method is compared with several traditional methods of corner and edge detection algorithm, the experiment result shows a good performance. The clustering method can achieve the corner and edge detection simultaneously.

In order to evaluate the anti-jamming capacity of the radar net under information warfare conditions, this paper adopts the projection pursuit method to convert the main performance indexes which affect the radar net anti-jamming capacity into one dimension projection value, offers their evaluation and ranking of such indexes and achieves the weights of the these evaluation indexes. This method does not only realize the evaluation of the radar net anti-jamming capacity but also provides a new method to evaluate such a capacity.

Introduced one ultrasonic ranging alarm device based on SN8P2501B microcomputer, it mainly included ultrasonic emission circuit, receiving circuit, keyboard, alarm circuit and the software. Compared with the traditional ranging methods, the system used 555 time-base circuit to produce ultrasonic, and designed a temperature compensation circuit to eliminate effect of sound velocity produced by the environment temperature. The practical application results show that the ranging system is stable , reliable and highly accurate, so the technology and methods adopted in the system are highly practical and worthy of being used abroad.

This paper focuses on the current development of military aircraft safety risk decision method is not enough application of projection pursuit method to calculate the weights of the evaluation indexes of a military aviation, comprehensive evaluation of different layout scheme. The available schemes were quickly ranked by their safety performance, the difficult problem with safety design of military aircrafts was primarily solved in the aeronautic project.

The effect of Nd on the mechanical properties of magnesium alloy AZ91 has been studied. The results show that the addition of 1wt.%Nd can refine the grain size, cause the formation of high melting point Al2Nd phase and reduce the amount of β-Mg17Al12 phase. and enhance the mechanical properties of magnesium alloy AZ91 at room temperature and 150°C.

The microstructure and mechanical properties of Mg-9Gd-2Y-1Sm-0.5Zr alloy have been studied by micro-analysis and tensile tests. The results showed that the alloy mainly consists of α-Mg matrix, Mg5Gd and Mg24Y5. With the increase of temperature, the tensile strength of the alloy increases at first and then decreases, and the peak appears at 250°C.

Because of the appearance of mobile office and distributed office in Internet communication system, which has brought great opportunities for development of real-time and interactive online evaluation system. In this background, this paper designs an OPC technology which is compatible with multiple internet distributed interface, it can realize the distributed online evaluation. This paper designs a direct switching algorithm procedure of OPC with multiple interfaces, so it can realize the evaluation of interactive and real-time. About the model and the level, this paper uses hierarchical model to evaluate network. Finally based on the evaluation of ideological education online as an example, we conduct the performance of the Internet online system for practice research, it is found that the Internet online evaluation system has well real-time and interactive features, it provides the theory reference for the research of internet ideological and political education.

As an important module of enterprise device management, spare parts inventory affects other strategies like equipment maintenance, overhauling, repairing etc. Furthermore, the normal production of enterprises and economic benefits are closely related with it. In this paper, spare parts are classified based equipment maintenance features [. After analyzing the dynamic and uncertain demand context, a probability inventory model which takes equipment downtime loss into account is presented [. A reasonable inventory costs is suggested through a lot of computing. The model and methodology have been demonstrated by a case study.

Because of the coating binder migration in cross-section of coating layer, the binder concentration will be different in z-direction of coating layer, which affect some properties of coated paper. The Paper studied the effects of pigment type, coating color solid content and dying temperature on binder migration and affected factors. The z-direction distribution of the coating binder which was tagged with Br in coating layer and its concentration in coating surface were examined quantitatively by using SEM-EDXA and ESCA analysis. The mechanism of binder migration was also proposed. The results indicated that the degree of binder migration is directly proportional to the drying temperature, that the increase of the ratio of calcium carbonate in the pigment content, coating surface binder concentration increased. The result also indicated that the degree of binder migration was increased with reduced the coating solid content.

The coating binder in cross-section of coating layer will be migrated, the binder concentration will be different in z-direction of coating layer, which affect some properties of coated paper. The paper studied the effects of coating progress on binder migration and affected factors. The z-direction distribution of the coating binder which was tagged with Br in coating layer and its concentration in coating surface were examined quantitatively by using SEM-EDXA and ESCA analysis. During coating process the drying rate, dwell time from coating device to dryer and coating weight affect the binder migration. The mechanism of binder migration was proposed. The results indicated that the degree of binder migration is directly proportional to the drying temperature and coating weight, but reduces with extending the dwell time.

The oxidation and corrosion behavior of Sn-9Zn-1Bi lead-free solder alloys with different P content were investigated by weighing the mass of the alloy, as well as the effects of P on the microstructure. The results indicate that the oxidation resistance and the corrosion resistance of Sn-9Zn-1Bi solder alloy can be enhanced significantly with the increase of P content. The microstructure observations show that P addition into Sn-9Zn-1Bi solder alloy can refine the microstructure and the numbers of dark rod-like Zn-rich phases are decreased with increasing of P addition.

By some assumed conditions and by Fick first law (first used for release behavior of microcapsules), the release dynamic equation of idealized microcapsules in liquid phase was established. With extraction method and spectrophotometer, the light absorbance of extracted liquid was measured, the release dynamics in liquid phase and some relatively release parameters were acquired. The experiment indicated: the release behavior of the CVL core permeated from the wall of microcapsules into the liquid phase matched with zero-order release equation basically.

The coating binder migration and concentration in z-direction of coating layer especially in coating surface influence the coated paper printing properties. The results indicated that with the increase of coating surface binder migration, the coated paper opacity decreases, and the K&N value decreases. The relationship of K&N value and binder concentration in surface of coating layer was linear, which indicated that compared to binder dosage concentration in coating color, the K&N value and coating surface binder concentration has higher correlation. The more uniform the binder distribution in cross section of coating layer, the greater the IGT.

The paper studied the effects of SMA as protective colloid on emulsification and micro-encapsulation process in the preparation of MF-resin microcapsules. The results indicated that pH value and the dosage of the SMA had important effects on zeta value and micro-encapsulation. The SMA dosage, emulsifying time and stirring rate influenced the capsule preparation, mean particle size and particle size distribution of microcapsules. The diameter became smaller with the increase of the amount of protective colloid. The applying amount of the SMA had an optimum value. The zeta potential just after emulsification was much larger than after reaction of MF in the preparation of microcapsules.

The Paper studied the effects of pigments and base paper on binder migration and affected factors. The z-direction distribution of the coating binder which was tagged with Br in coating layer and its concentration in coating surface were examined quantitatively by using SEM-EDXA and ESCA analysis. The results showed that the increase of the ratio of calcium carbonate in the pigment content, coating surface binder concentration increased, and coating surface binder concentration increased with the increase of particle size of pigments. The result also indicated to small base paper absorbency, coating surface has high binder migration level, the coating layer bottom (base paper direction) has low binder concentration. To high absorbency base paper, the opposite is true.

The paper studied the microcapsule particle size, size distribution and its influencing factors with melamine formaldehyde resin (MF-resin) as wall and CVL as core. The results indicated that the microcapsules mean particle size decreased, size distribution became narrow with the increase of emulsifying time and shear rate. Low pH value would make the microcapsules have rough surface morphology and large particle size.

The Paper studied the effects of coating color on binder migration and affected factors. The z-direction distribution of the coating binder which was tagged with Br in coating layer and its concentration in coating surface were examined quantitatively by using SEM-EDXA and ESCA analysis. In coating colors the coating solid content, the binder dosage and type affects the binder migration. The mechanism of coating color on binder migration was also studied. The results indicated that the degree of binder migration was increased with reduced the coating solid content or added more dosage of coating binder. In low dying temperature the SB-latex was prone to migrated to coating layer surface than starch, the opposite is true in high dying temperature.

The paper studied thermal properties of MF-resin microcapsules. The paper established the non-liquid release dynamics equation in ideal mode. The results indicated at 400°C or so microcapsules began to severe weight loss, which explained the heat resistance of microcapsule could completely satisfy the requirement of coating production process. The results also showed the microcapsule thermal weight loss was in line with zero-order release before 373°C, and after 373°C accorded with first-order release dynamics equation.

The paper studied the preparation and micro-encapsulation of pressure sensitive essence microcapsules with MF resin and UF resin as double wall by using the in situ polymerization method, and the optimal preparation conditions were also studied. The microcapsules were characterized on structure, morphologies, thermal properties, mean particle size and size distribution. The experiment illustrated that the wall of microcapsule consisted of the MF resin and the UF resin had been synthesized in the process of preparation, the essence oil was encapsulated into the microcapsules, the mean particle size and size distribution was well-proportioned and narrowed respectively, the particle morphologies were single core and global, the wall was hermetically sealed.

The coating binder migration and concentration in z-direction of coating layer especially in coating surface influence the coated paper printing properties. The results indicated that with the increase of coating surface binder migration, the coated paper opacity decreases, and the K&N value decreases. The relationship of K&N value and binder concentration in surface of coating layer was linear, which indicated that compared to binder dosage concentration in coating color, the K&N value and coating surface binder concentration has higher correlation. The more uniform the binder distribution in cross section of coating layer, the greater the IGT.

The traditional CAPP system pays much attention to the intelligent generation of the parts process route or pursuit integration of CAD and CAPP and CAM, but it has exposed many shortcomings in the process management of process design and approval. In order to solve the problem of information transmission and process reengineering, this paper discusses the application of work flow technology in the CAPP system, and analyzes the process design and approval process based on Petri Nets model, and finally explains database design and realization of process workflow and the control mechanism of workflow engine based on state transition on emphases. Through the practical application, the system can greatly improve the efficiency of design and management of process, the process design is more flexible and more standardization.

The electromagnetic technology of drying Paper is that we use the principle of electromagnetic heating to dry paper, which is a new paper drying technology and quite different from the traditional steam drying . This thesis is based on the principle of electromagnetic induction, combined with technical requirement of paper drying. We used the AutoCAD software design a laboratory drying device with electromagnetic, and analyzed various parts of the selection and structure, by using UG software solid modeling, assembly modeling and other modules design a three-dimensional simulation of the various parts of the electromagnetic dryer device. The simulation graphics shown that the simulation design of electromagnetic dryer is more success, which can meet the requirements of drying paper evenly.

Paper electromagnetic drying technology is a new paper drying technology different from traditional steam drying. Today, environmental pressure deteriorating, energy crisis approaching, doing researches on paper electromagnetic drying technology has a special meaning, especially to high speed toilet paper machine which is truly needed and has a vast developmental potential. This thesis is based on electromagnetic dryer and steam dryer study. And the changes measured in the experiment at diverse temperatures and quantities in the experiment has shown a higher efficiency of electromagnetic drying technology than conventional steam drying technology.

By use of ANSYS software, Without coated high temperature resistant coating and coated with high temperature resistant paint two model to simulate heat transfer analysis, so as to explore the preparation of the high temperature resistant coating insulation heat preservation effect.

Experimental choose methyl-trichlorosilane, di-methyl-dichlorosilane and phenyl trichlorosilane synthetic organic silicon resin, add white mica powder, aluminum silicate, titanium pigment, zinc phosphate as packing, system high temperature insulation coating. For after high temperature resistant coating surface coating of tin model coating physical mechanical properties and high temperature resistant, heat insulation temperature difference of performance test, the results indicate that the system of high temperature resistant coating resistant to 400 ~ 500 °C high temperature, and has good high temperature resistance, heat insulation performance, etc.

Adiabatic shear bands (ASBs) develop generally during high strain rates. This paper investigates the transformation induced plasticity (TRIP) effect during ASBs formation at high strain rates in high manganese TRIP steels containing initial austenite and ferrite by EBSD technique. Results show that TRIP effect takes place mainly before the formation of ASBs. After ASBs formation, TRIP effect is strongly restricted by the size effect, the increase of stacking fault energy (SFE) and even inverse martensitic transformation due to the rise of temperature. The TRIP effect before ASBs formation contributes to the resistance of adiabatic shear failure. Dynamic recrystallization driven by subgrains rotation occurs within ASBs, and ultrafine grains often show strong shear textures with twin relationship owing to slip mechanism.

Zinc oxide (ZnO) nanorod arrays were fabricated on ZnO:Al seeded Si substrates with various reaction temperatures using a low temperature hydrothermal method. The morphology and structure of ZnO nanorod arrays were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). It reveals that the ZnO nanorods grow vertically on Si surface with (002) preferential orientation. The transmittance spectra show the ZnO nanorod arrays fabricated at low temperatures have high transmittance in the visible region and decrease with reaction temperature increasing. Moreover, the same trend was also observed in the reflectance spectra of the ZnO nanorod arrays. The optimal reaction temperature is of 120 °C for ZnO nanorod arrays with high transmittance (~80%) and low reflectance (~10%) in the visible region. The superior optical properties make ZnO nanorod arrays promising for applications as transparent electrodes.

The 5CB liquid crystal as defects will be introduced to one dimensional photonic crystal, taking advantage of temperature property of liquid crystal refractive index, the transmission spectrum of one dimensional liquid crystal defect photonic crystal defect modes was researched by the transfer matrix method(TMM). The numerical results indicated that when the temperature went up, one dimensional liquid crystal defect photonic crystal defect modes removed towards the long wavelength. When the temperature increased from 273k to 320k, the defect modes wavelength from 5121nm drifted to 5508nm, the wavelength shift was 387nm and the maximum of temperature sensitivity was 10.85nm/K, it was also observed that the temperature sensitivity decreased as the temperature increased.

The high pressure die casting (HPDC) process of an ADC12 aluminum alloy auto part is researched by the software ProCAST and FLOW-3D, respectively. The possible HPDC defects of the auto part are analyzed. The difference of the filling process with the same technological parameter is studied. Compared with the simulation result of ProCAST, FLOW-3D software simulation result is closer to the die casting of the actual production.

Low pressure die casting (LPDC) process of a copper-alloy tap was simulated by the finite element software ProCAST. The casting defect and its reason were analyzed. The optimized design was discussed and the simulation was validated against the low pressure die casting experiment. Results showed that the main defect is misrun and its reason is that the melt solidifies too fast. It’s well solved by increasing the wall thickness of the relational pipe properly. The result agrees with the experiment.

Pumpkin（Cucubita pepo L.）seedlings were exposed under different low temperature-light regimes to investigate the responses of photosynthesis and chlorophyll fluorescence to the stress. The results indicated that the contents of chlorophyll increased at first day after treatment and then decreased under special temperature(15/5、20/10、25/15°C )and poor light(50、150、250μmol•m-2•s-1).The net photosynthetic rate, evaporation rate, stomata conductance and intercellular CO2 concentration increased one day after treatment and then decreased, stomata limitation increased above15/5°C special temperature and special poor light. However, under 15/5°C temperature and special poor light, the net photosynthetic rate, evaporation rate and stomata conductance decreased, and intercellular CO2 concentration increased stomata limitation increased in 4 days after treatment then decreased. Ft、Yield(F/Fm’)、qP decreased under special temperature and poor light.The change of these parameters were less under the light density of 50μmol•m-2•s-2 than other light densities, which means that poorer light reduced the sensitivity of pumpkin to low temperature and increased the photochemical activity of PS, but the photochemical quenching (qP) decreased and the non-photochemical quenching(qN) increased at the same time.

Measurement System Analysis is of vital importance in a Six Sigma project. Variable measurement system takes the advantage of being practical and efficient. This paper focuses on the effect of sample size selection on error estimation of repeatability and reproducibility(R&R). After the discussion about the interval estimation of relevant statistics of R&R, this paper continues to analyze how the confidence interval is influenced by the number of operators, the number of samples and times of repeating measurements and a reasonable sample size in assessing the R&R of a measuring system is established for more effectiveness and efficiency.

A series of polyurethaneurea (PUU) nanocomposites based on clay-like sepiolite (Sp) with the modification of γ-aminopropyltriethoxysilane (KH550) were prepared via in situ polymerization from poly(propylene glycol), tolylene-2,4-diisocyanate (TDI) and 3,3'-dichloro-4,4'- diamino-diphenylmethane(MOCA). Morphology and structure of nanocomposites were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The results indicated that KH550-Sp was dispersed homogeneously in the PUU matrix, which facilitated the formation of chemical bonds between KH550-Sp and the hard segment of PUU. The thermostability and mechanical properties were studied by the thermogravimetric (TG) analysis and tensile tests. The results showed that the onset decomposition temperature and tensile strength of nanocomposites was higher than those of pure PUU.

Wavelet Neural Network (WNN) is a new form of neural network combined with the wavelet theory and artificial neural network. The wavelet neural network model based on Morlet wavelet and the corresponding learning algorithm were studied in this paper. And through learning the wavelet neural network model is applied to all kinds of engineering examples, it proved that the wavelet neural network prediction model which has a more flexible and efficient function approximation ability and strong fault tolerance, and with high predicting precision.