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The simulation of distribution automation troubleshooting and the functional design of training system software is discussed by this article, Including: basic platform capabilities, the decision analysis of auxiliary power failure, Power operation mode for load transfer analysis, the ring analysis of grid operation mode , the training simulator of distribution network and the data synchronization of the simulation system diagram and mode. The simulation of distribution automation troubleshooting and the effect of training system operation show the validity and effectiveness of the method.

The paper studies integrated protection methods of pre-Qing architectural heritage area in Liaoning with Geographic Information System (GIS) technology. First of all, pre-Qing architectural heritage in Liaoning is investigated, and the geographic information database is established. Then the composition of pre-Qing architectural heritage area in Liaoning is analyzed, and its value is evaluated. Finally, the traffic system of pre-Qing architectural heritage area in Liaoning is planned in order to facilitate its future protection. This research shows that the application of GIS for the overall protection of pre-Qing architectural heritage area in Liaoning is scientific, reasonable and feasible. Application of GIS technology can expand and innovate the ideas and approaches of traditional heritage protection, and provides a firm data foundation and powerful technical support for a better research and protection of this large scale type of heritage like heritage area.

In order to eliminate cracks in the chromium coating, a novel method named flexible extrusion assisted chromium electroplating was proposed. The bright and crack-free chromium coatings were electrodeposited by using the perturbation and extrusion of hard and insulating particles. The prepared deposits were characterized by scanning electron microscope (SEM) and three-dimensional topography. The testing results showed that the surface was very smooth and there was no micro cracks in the coating. Micro hardness of the electrodeposited layer was also tested. It was confirmed that the chromium coating electrodeposited with rotating cathode in hard particles had high micro hardness as to 850HV and the micro hardness could be controlled by the process parameters. The rule of the micro hardness was concluded by analyzing current density and rotating speed. In addition the results of salt spray test and electrochemical polarization curve showed that the coating deposited by new method had higher corrosion resistance than that by traditional method.

As networks to be flattened, a direction has been put forward clearly by Telecom operators that Optical Line Terminals (OLT) of Gigabit Passive Optical Network (GPON) should become aggregation [1] OLTs, which makes them to work as both aggregation switches and edge access devices. According to this requirement, a scheme that realizes Routing [2] Information Protocol (RIP) on GPON OLT is put forward after deep analysis of GPON system [3] [4] [5] and RIP. Results shows that IP routing on GPON OLT is realized, which allows OLTs to work on the network layer, at the same time simplifies the broadband network levels and increases the reliability of the network.

If the wear and the replace frequency of rubber platen rollers of PROTOS1-8 Cigarette Machine can be reduce, easily lead to the stable of the force of paper feed and reducing the time of maintenance and spare parts consumption. However, there is no a new device for adjusting pressure of platen rollers. To solve this problem, a new type of device for adjusting pressure of platen rollers is designed. The three movable reference wheels used to test and adjust the gap instead of the reference plane. Application results shows that using the new device can effectively solve the excessive wear of the rubber platen roller. The amount of rubber rollers for replacing is reduced to 6 compare of 22 before and the maintenance time is reduced to 19 hours compare of 115 hours before during the statistical time. It also improve the operating efficiency of this type of equipment.

Nitrogen oxides are dangerous toxic pollutants to human health and the atmospheric environment.[ Boilers NOx emissions as a major source of energy conservation is the most important task. The generation principles and influencing factors of coal-fired power plant boilers NOx were discussed. The current mechanism modeling had limitations and shortcomings, by studying reversed modelings and artificial neural network theory, Elman neural network was used to build the prediction model of coal-fired boilers NOx emissions. By comparing the predicted results with the true results, the convergence speed and accuracy of the method are both satisfactory to provide reference and guidance, and it provides new ideas and new ways for thermal power NOx measurements.

The heat transfer and pressure drop characteristics for water flowing in four spiral coils with different shapes and different sizes were experimental studied. Reynolds number range from 4000 to 9000, volume flow rate range from 200 to 350 L/h and heating power range from 80-350 W. Based on the experimental results, the regularity of Reynolds number and heating power influencing on heat transfer and pressure drop characteristics was analyzed and discussed. The results indicate: the Nu increases with increasing Re, the greatest average heat transfer coefficient appears in the smaller circular spiral coil. The heat transfer coefficients increase with increasing heating power, the greatest average heat transfer coefficient also appears in the smaller circular spiral coil. The pressure drops increase with increasing Re, the pressure drop in big ellipse spiral coil is greatest. The resistance coefficients gradually decrease with increasing Re. The resistance coefficient of small circular spiral coil is always greatest, and the resistance coefficient of big circular spiral coil is smallest.

The main objective of this study is to investigate the economical distribution of generator load based on the Lagrangian Multipliers. The reasonable economical distribution of generator load based on the lagrangian multipliers model is established in this paper, which uses the appropriate mathematics optimized algorithms whose computation precision is higher and convergence characteristics is good too. This algorithm improves the efficiency of computation, which is very significant in engineering

Based on FEM, the paper presents a reasonable four teeth end mill model to simulate the process of metal milling, which uses the adaptive meshing criteria.This model simulates a typical work-piece chip breaking process with different cutting speed and feed ratio, which gets the cutting forces curves and the total status of residual stress distribution.

30 MW straw power turbines are most suitable in the major corn producing areas in Northeast China. This paper takes straw power plants that are already used in practice as examples to demonstrate the technological and economical analysis of straw power-generating projects. The research results show that straw cogeneration is advantageous in energy utilization rate, economic profits, and etc.

The quantity of jaw crusher teeth plate consumed in crashing process directly affects the costs. Based the FEM method, the 3-D jaw crusher teeth plate shape model is established in this paper. This paper studies the stress distribution laws with three types of teeth shape. Through contrasting the results of analysis and data of malfunction teeth plate, it is can be drawing that the stress distribution laws, which can be used in optimizating design of teeth plate shape. It extends the using life and improves the crushing efficiency.

An introduction is made of a new method, which use computer to get an accurate unfolding drawing, to calculate the cutting stock of chemical container’s connecting pipe. Practice proved that this method is not only fast and convenient, but also accurate and reliable.

The working medium of the pneumatic control system is air, which is delivered to each branch pipe through the role of the governing valve , and then the divided gas delivers the compressed air to each solenoid valve and pneumatic control valve. The solenoid valves and pneumatic control valve is connected through terminals and PLC, PLC obtains corresponding signal and makes judgment, conveying signal which is delivered to the solenoid valves and pneumatic control valve to achieve ventilation and breathe action, and finally the gas reaches the cylinder . The cylinder can complete the valve body on and off, so as to realize the pneumatic system of the automatic control.

Hydroxycamptothecin (HCPT) loaded PLA nanoparticles were prepared by a facile dialysis method. Three main influential factors, PLA concentration, ratio of HCPT to PLA (wt/wt), dialysis bags with different molecule weight cutoff, were evaluated using an orthogonal design, gave the nanoparticles with an average diameter of approximately 226.8 nm and fine drug loading content (5.16%, w/w). The in vitro drug release studies exhibited a slow and prolonged release profile over 30 days. It is concluded that the new method to prepare HCPT-PLA nanoparticles resulted in improved formulation characteristics including small size, high drug loading capacity, and long sustained drug release.

A series of new chromium(III) complexes bearing fluoro-substituted β-diketiminate ligands have been synthesized and characterized by IR and elemental analyses. When activated by modified methylaluminoxane (MMAO), these Cr complexes exhibited moderate or high activities for ethylene polymerization (up to 370 g.mmol-1.h-1). Various reaction parameters such as reaction temperature and Al/Cr ratio were investigated in detail. Further more, it was found for the first time that the catalytic behaviors of Cr complexes can be greatly influenced by the electronic effect of fluoro substituents. The introduction of electron-withdrawing fluoro groups to ligands can improve the catalytic performances compared with those bearing alkyl groups, but incorporation of more fluoro atoms would then decrease the catalytic activities.

Design the 3D pattern of jacquard fabric which can be produced as wall covering, we found that choose decentralized irregular image and make the image deformation is not obvious; floating length can’t be too long and tightness are almost same everwhere to make the fabric smooth; when match designing, rendering algorithm must be from the center to keep the two sides from deformation; the weight and length of the pattern should be design base on the image to make the joint invisible.

Sound source localization is always of great value in many engineering applications. In this paper, a new instrument is designed to accomplish the purpose of localizing the sound source by a relatively compact structure. This bionics structure is designed to mimic the localization function of the ears of the parasitoid fly Ormia ochracea, and it consists of three elastic diaphragms, three bars which connected to the diaphragms, and the other mechanical components. The analysis of this structure’s dynamic behavior shows that the incident angles of the sound have special relationship to the responses of this instrument, and the incident angles can be estimated by detecting the vibrations of the three elastic diaphragms. Compared with traditional microphone arrays, this instrument has the advantage of compaction and higher integrated level.

For increasing heat efficiency and preventing crack resulting in thermal stress, the laws of heating slab must be accurately studied. The thermal stress field distribution in slab heating process is researched, which adopts FEM and bases on the transient non-linear heat analysis theory. The 3500 slab heating model is established in according to the heating technique in mills. The factor of conduction coefficient and specific heat changing with temperature also are considered. The heating process is simulated and the influence laws of furnace temperature and heating rate are drawn, which is very significant in engineering.

A representative volume element is chosen to act as the research object to analyze the temperature field of the dispersion fuel elements. The thermal analysis is carried out for the thermal behaviors using FEM. The results indicate that with the volume fraction and the heat generation rate of the fuel particles increasing, the temperature and the gradient of the temperature in the matrix and the cladding increases markedly.

A representative volume element is chosen to act as the research object to analyze the thermal elastoplastic behavior of the dispersion fuel elements. The large strain elastoplastic analysis is carried out for the mechanicalbehaviors using FEM. The results indicate that with the volume fraction of the fuel particles increasing, the Mises stress and the equivalent plastic strain in the matrix increases, and the first principal stress and the equivalent plastic strain in the cladding increases markedly.

Studies on orientation mechanisms of the auditory systems and research of bionic structures of subminiature creatures, especially of the parasitoid fly Ormia Ochracea which has a remarkable ability to detect the direction of the incident sound stimulus despite of its tiny body size, may provide preferable solutions for the miniaturization of acoustic localization structure. In this paper, the bionic acoustic sensing device are set up and taken as the research object to find feasible orientation mechanisms, and experiments on bionic acoustic sensing device are conducted after the test system has been established.

The control arms, as an important part of automobile components, are widely used in auto assemblies. The ball joint sealing of control arms is a key process to chassises assembly and the sealing quality directly determines the lifespan of steering systems of automobiles. In this paper, based on the aluminum control arms, a precise control system of revolving-riveting equipment spindle displacement was developed and the effect of riveting equipment spindle displacement on torque of ball joint sealing was studied through experiments method. The results showed that the torque of ball joint is directly related to the displacement of spindle, and a better sealing quality can be achieved when the displacement of spindle was in a reasonable range. The research will provide elementary technical support to the ball joint sealing of automobile control arms.

Adopted the Lagrange quality point coordinate system description method used the FEM analysis software, the reasonable two-dimension heat-mechanic coupling orthogonal cutting model is established in this paper, which uses the ameliorated Coulomb friction theory to simulate the friction status between the chips and tools. This paper simulates the cutting process with different friction coefficient. It can draw conclusions that the cutting forces and the residual stresses of machined surface are increasing with the raising of touching length of rake face and chip, the raising of cutting temperature. The friction coefficient has the important effect on the machining quality.

The cold rolling of slab is analyzed by using elastic-plastic and heat-mechanic coupling FEM with the nonlinear method. The distribution of residual stress was analyzed mainly in this paper. It is indicated by the results that the residual stress in surface layer of slab material is the pressure stress and inside the plate is the tension stress under the smaller press quantity, the residual stress in surface layer is the tension stress and inside the slab is the pressure stress under bigger press quantity, the maximum residual tension stress in the slab becomes bigger with the increment of the reduction.

Polycrystalline α-HgI2 films have been grown through combining vertical deposition method with hot wall vapor phase deposition (HWPVD) method. The influence of the α-HgI2 seed layers on the structural and electrical properties of the polycrystalline α-HgI2 films was investigated. It is found that the α-HgI2 seed layers play an important role in reducing the grain sizes, increasing the density improving the crystallographic orientation and electrical properties of the polycrystalline α-HgI2 films.

A series of parametric tests have been conducted to investigate the effect of curing period and cement content of the specimen on fracture energy of cement stabilized aggregate. By means of three-point bending method, the fracture energy of cement stabilized aggregate was measured. Four specimen curing periods (14 d, 28 d, 60 d and 90 d) and four different cement contents (4%, 5%, 6% and 7%) were used. The results indicate that the fracture energy of cement stabilized aggregate is increasing with the increase of specimen curing period. Besides, with the increase of cement content, there is a tendency to decrease in the fracture energy of cement stabilized aggregate. The ability of cement stabilized aggregate to resist crack propagation becomes weaker and weaker with the increase of cement content.

The aim of this study was to study the effect of curing period and cement content of the specimen on flexural strength and flexural modulus of elasticity of cement stabilized aggregate. Four specimen curing periods (7 d, 14 d, 28 d and 60 d) and four different cement contents (4%, 5%, 6% and 7%) were used. The results indicate that the flexural strength and flexural modulus of elasticity of cement stabilized aggregate are increasing with the increase of specimen curing period. Besides, with the increase of cement content, there is a tendency to increase both in the flexural strength and flexural modulus of elasticity of cement stabilized aggregate. The actual cement content should be chosen according to the actual condition of the project.

Single sided resistance spot welding (SSRSW) developed from resistance spot welding (RSW) is a feasible plan to join vehicle structure to closed-form tube and is increasingly used in automobile manufacturing. A ring spot weld can be formed between the two workpieces during this process. The weld strength is critical to the performance of vehicle. The mechanical property of the ring nugget, however, is lack of attention. In this study, a simulation model of workpieces with ring nugget for tensile-shear test was established and the stress and strain distributions around the weld were researched in detail. It was found that the maximum stress is generally concentrated at the out edge around the ring nugget. The failure region, however, may be in the heat affected zone (HAZ) instead of in the place of maximum stress, which should be judged by stress failure criteria (SFC) in the model. In addition, the tensile stress and shear stress on the surface of the lower sheet and upper tube were illustrated.

Due to bad welds including small button, weld expulsion, and weld whisker etc., it is studied that the effect of constant and variable electrode force with servo gun on the weld quality of high strength steels with different thickness and materials. The results show that the electrode force plays an important role in resistance spot welding of AHSS as well as that of mild steels. Under the same welding current and time, better welds with higher tensile shear strength and larger nugget size can be obtained by optimizing electrode force curve using servo gun. The solutions could supply reference to study the prospect of servo gun in the joining of high strength steels.

Sound source localization is always of great value in many engineering applications. In recent years, studies on orientation mechanisms of the auditory systems and research of bionic structures of subminiature creatures, especially of the parasitoid fly Ormia Ochracea which has a remarkable ability to detect the direction of the incident sound stimulus despite of its tiny body size, may provide preferable solutions for the miniaturization of acoustic localization structure. In this paper, the bionic acoustic sensing device are set up and taken as the research object to find feasible orientation mechanisms, and the dynamics of the bionic mechanical coupled diaphragms are analyzed. These works provide the basis for the manufacture of experimental acoustic sensing device. In the last part of this paper, experiments on bionic acoustic sensing device are conducted after the test system has been established. The measured data and the analyses based on the measured data demonstrate that the modeling methods and theoretical study in this paper are correct.

The analytic formula of the thickness demarcation circle during hydroforming of double-cone tube is derived by using the mechanical analysis and the total strain theory. The effect of friction coefficient, expansion coefficient, ratio of axial stress to internal pressure, length of feeding zone, and initial thickness of tube on the thickness distribution can be given by this formula quantitatively, and the analytic results were compared with the FEM analysis and experimental results. The results show that with the increasing of friction coefficient, the ratio of axial stress to internal pressure, the relative length of feeding zone, the distance between thickness demarcation circle and tube end decreased, that means the increasing of length of the thinning zone, and with the increasing of relative thickness of tube blank, the distance between thickness demarcation circle and tube end increased, that means decreasing of length of the thinning zone.

This paper presents a proposed system based on LabVIEW for data acquisition and monitoring of manufacturing process in machine tools with CNC. It was applied to evaluate work piece dimension and failure analysis in real time. The proposed system was developed and tested initially in a CNC milling machine with open architecture. Furthermore, it can be extended to other machines and processes, lines or cells of mass production as well. And it was applied in some factories and workshops now.

Toll evasion is a known challenging problem in expressway transportation. Existing solutions mainly rely on the audit by people on the spot. However, with the increase of expressway networks, this kind of methods become less practical and lead to low efficiency. Considering this deficiency, this paper presents a method based on data mining to automatically assist the toll audit. Our method not only takes use of the data recorded from the expressway toll system, but also brings convenience to the auditing process.

Firstly, the geometry condition of useful wrinkles during the hydroforming of double-cone tube was given. Then the stress condition of useful wrinkles was given by formula between the parameters of wrinkles shape at the end of axial feeding and internal pressure, hoop stress and axial stress. The analytical results were compared with the FEM analysis and experiments results. The results show that the useful wrinkles must meet both the geometry condition and the stress condition. The geometry condition of useful wrinkles is that the area of arbitrary length of wrinkles is a little smaller than the area of corresponding die cavity. The stress condition of useful wrinkles is that shape parameter G is not smaller than the radius R at the top of middle wrinkle. That means the increment of thickness strain dεt is positive and no thickness thinning will occur during the calibration. When the wrinkles didn’t match geometry condition, the dead wrinkles or bursting will take place. And when the wrinkles didn’t match stress condition, the bursting at top of middle wrinkle will occur during the calibration.

Tailor-welded blanks (TWB) have been widely used in automobile industry. In this paper, expanding experiments are carried out for tailor-welded blanks both with curved seams and straight seams, and the formability of tailor-welded blanks with curved seams has been studied and compared with tailor-welded blanks with straight seams. The effects of thickness ratios and seam radius on the formability of tailor-welded blanks with curved seams and straight seams are deduced, separately. In the end, the relationships between the shapes of welding seams and forming heights, and relationships between the thickness ratios and forming heights are given, which are valued to the designers and processers of tailor-welded blanks.

Tailor welded blanks had been widely used in automobile industries. In this paper, the formability of tailor-welded blanks with curved seams had been studied in experiments, and compared with that of tailor-welded blanks with straight seams. For tailor welded blanks with curved welded seams, the effects of thickness ratio on the limited forming height are the same under various welded seam shape, and the limited forming heights are decreased and then increased with the increase of thickness ratio, which different to that obtained from tailor-welded blanks with straight seam. The reasons that the shapes of welded seam how to influence the formability of tailor welded blank are deduced in the paper. Results show that the shape of the welded seam can change the blank’s deformation condition, which one of the main factors of determining the sheets formability.

For reasons of cost and weight, light gauge sheet is used wherever possible for metal fabrications. In sheet metal forming the process is to gather the metal into defined areas. The pulley forming process is no exception and is achieved by superimposing axial loads on top of radial loads using a pressure-controlled tailstock. Whilst the headstock-mounted tooling is fixed, that part held on the tailstock can be powered axially under controlled pressure. This pressure is governed by the width of the workpiece which changes during the forming process. Experiments have been designed to provide an understanding of the pulley forming process and to verify numerical models. The latter has been taken the form of finite element simulations to enable prediction of metal flow, tool forces and potential sources of defects and failures. There are three objectives for conducting the experiments which have been investigated in this paper: 1. providing data to define the movements of the forming tools for the finite element model, including displacements and velocities, 2. understanding the effects of the pulley forming operation on the flow of material, and 3. validating the finite element model.