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Double Helix Resistor (DHR) can be used to establish AC resistance standard. Because the short-term stability of the DHR is very important during the process of quantity value dissemination, the DHR should be kept in a temperature-controlled environment. This paper presents a Fuzzy-PID temperature control method based on MSP430F149, the overshoot and adjustment time of the temperature control system can be reduced by using the Fuzzy control rules to adjust PID parameters. A special resistance box is designed to place DHR and decrease the exterior EMI effectively. At last, Fluke 8508A is used to measure the resistance of DHR. The measurement results show that the short-time relative stability of DHR is enhanced to 3×10-7after applying the presented temperature control system.

The pricing decision of consumer goods manufacturing enterprise is a very important part in its business strategies. Price of the product is directly related to the ability to obtain the expected earnings. In this paper, based on the analysis of the characteristics of durable consumer goods and the factors that affect the price, considering the continuous product innovation and diversification of consumer demand, psychological factors of consumers, as well as the price timeliness, starting from the quantitative point of view, a dynamic pricing model of durable consumer goods aimed at the maximum value of products was set up. Finally, a numerical example solving by the genetic algorithm was given to verify the feasibility of the model.

There are relevant reports on preparing TiB2 particle reinforced metal matrix composite (MMC) anti-wearing coating by plasma spraying and HVOF spraying methods successfully. The research uses electric arc spraying with low cost and convenient operation to prepare four TiB2 particle reinforced composite coatings with high bonding strength and uniform microstructure. It makes comparative study on elevated temperature erosion actions of coating and 45CT of electric arc spraying. The results indicate the coating has excellent erosion wearing resistance. TiB2 particles in M-TiB2 coating have small size, have good unity with metallic matrix, and are distributed on metallic matrix with high hardness relatively uniformly, and porosity of coating is low. Such MMC coating microstructure feature avoids micro-cutting of coating effectively, and reduces plastic deformation and material transfer of wearing surface. The coating has excellent erosion resistance.

With the development of modern industry, more and more semiconductor-based devices have been used widely. Such equipment presents nonlinear impedance to the utility, generating large harmonic currents with well known adverse effects, such as low power factor, low efficiency and destruction of other equipment. Also, some precision instruments and communication equipment will be interfered. Therefore, utility power quality has become an important issue recently. This paper presents a hybrid active filter including two functions: current harmonic detection and reactive power compensation. The current harmonic detection is based on. The reactive power compensation utilizes the measured voltage and the estimated fundamental current to calculate reactive power. After the above information has been calculated, the corrective current reference signals can be generated for the active filter. In this way, the two control functions are integrated together so that one active filter can accomplish two functions simultaneously. The system is modeled in MATLAB SIMULINK to consist of the non-linear loads, with a hybrid active filter to compensate for the harmonic current and reactive power. The simulation results show that the proposed hybrid active power filter has the expected performance.

The boiler system in power plant consists mainly of a steam-water system and combustion system, which produce a high-pressure superheated steam to drive a generator in order to produce power. The steam temperature control of the boiler system is a critical operational consideration. Parameters of boiler producing process must be controlled strictly. But the boiler system has high nonlinearity, large delay, strong coupling and load disturbance. Therefore it is difficult to develop practical mathematical model of the control object using the traditional PID control. In order to realize the optimal control of steam temperature, this paper presents the adaptive fuzzy-PID control Strategy. Simulation results based on MATLAB show that the proposed strategy can largely improve the system response performance compared with the traditional PID control

The research uses electric arc spraying with low cost and convenient operation to prepare four TiB2 particle reinforced composite coatings with high bonding strength and uniform tissue. It makes comparative study on elevated temperature erosion actions of coating and 45CT of electric arc spraying. The results indicate the coating has excellent erosion wearing resistance. TiB2 particles in M-TiB2 coating have small size, have good unity with metallic matrix, and are distributed on metallic matrix with high hardness relatively uniformly, and porosity of coating is low. The coating has excellent erosion resistance.

Peroxynitrite can be highly efficient catalyzed to harmless products with a turnover frequency 34.5 s-1by micromolar concentration of water-soluble iron porphyrin, 5, 10, 15, 20-tetrakis-(4-carboxyphenyl)-porphyrin-Fe(III)-chloride (T(p-COOH)PPFe(III)Cl). Then we used spectroscopic and kinetic to study its decomposition mechanism and rate in bionic environment (25 mM sodium bicarbonate). The data reveal that this catalytic reaction is a recyclable reaction. Peroxynitrite is decomposed to nitrate (NO3-) and nitrite (NO2-) through forming [oxoFe(IV)]+intermediate. Moreover, the [oxoFe(IV)]+intermediate is reduced back to the starting porphyrin. It is noted that the oxidized iron porphyrin can be reduced by the reducing agent in the solution. In addition, we also find the catalytic rate constant is higher in the presence of sodium bicarbonate than the absence of sodium bicarbonate. They are 1.26×106M-1s-1and 1.17×106M-1s-1, respectively.

This paper presents a digital compensation device based on two multiplying digital-to-analog converters (M-DAC) whose reference voltages are the same standard AC signals. The output of two M-DACs, which is controlled by software coding, are used as the in-phase and the quadrature component through a reverse proportional amplifier and a derivation circuit respectively. Then the four-quadrant compensative signal can be got after the in-phase and quadrature components have been synthesized. The resolution of digital compensation device is determined by the M-DAC, and usually can be reached to 10ppm of the reference voltage. Measurement results show that the linearity of the presented digital compensation device is about 3.7×10-5.

In this paper ammonium molybdophosphate (AMP) and ammonium molybdophosphate-zirconium phosphate-silica (AMP-ZrP-SiO2) were prepared as trace Rb+and Cs+adsorbents. The two showed good adsorption performance for trace Rb+and Cs+when dealing with the salt lake brine. AMP-ZrP-SiO2has better hydraulics performance, and is more suitable for column adsorption. The adsorption mechanism, enthalpies (ΔH0), Gibbs free energies (ΔG0), and activation energies (Ea) of Rb+and Cs+from salt lake brine by the two adsorbents were investigated. The results show that the adsorption processes of Rb+and Cs+on AMP and AMP-ZrP-SiO2are spontaneous and endothermic. The adsorption order of various ions on the two adsorbents is Cs+>Rb+>K+>Mg2+>Na+>Li+by comparing their Gibbs free energies. Through the analysis of activation energies indicates that AMP-ZrP-SiO2is more efficient than AMP in the enrichment process of trace Rb+and Cs+.

The internal combustion engine should be enlarged the cylinder diameter for the Power requirements. In order to ensure the engine to work normally, it is needed to compute the strength of the connecting rod. Through adopting ANSYS software, the three-dimensional computational model is constructed, and the stress analysis is carried out. We can learn the stress field of process of deformation. Through calculation the stress and strength of connecting rod are derived. Using the stress which was calculated from ANSYS we can decide the Safety of connecting rod. In general, the analysis is meaningful to optimize the design of connecting rod.

In this paper, the elasto-plastic dynamic analysis on dynamic failure behaviors of steel double-layer grids supported by tridimensional truss columns used in a gymnasium with the function of earthquake victims shelter under disaster earthquake is carried out under EL-centro wave with SAP2000, and the appraisal results on their anti-failure performances are presented under strong earthquake action based on the plastic-hinge theory. In the analyses, the geometric and material nonlinear effects are considered simultaneously based on the plastic-hinge theory. The plastic development level of the rod, the deformed shape and the failure type and the ductility are estimated by plastic hinge principle. The results show that the failure model of the structure under the earthquake wave action is the complicated combination of strength failure and elasto-plastic dynamic local buckling in deferent areas of the structure; When the structure reached its failure critical limit, the development of the plastic hinges is not sufficient and only 5.11% of the rods enter into their plastic stage; Its critical failure peak acceleration of EL earthquake wave when applied in the combination of three directions is 705gal and can be served as earthquake victims shelter in the area of 8 degree seismic fortification; Its displacement ductility coefficient is 2.39,which shows the structure owns good energy dissipation capacity.

By adopting CFD numerical simulation software, the steady numerical simulation of original engine inlet is carried on. On base of the original one, two new inlets are redesigned and their velocity fields are analyzed. From the simulation of CFD, we can learn that with the different inlet, the average flow velocity increases when the swirl ratio rises in same cross-section. Then the experiment of inlets with different geometry is carried on. Considered various kinds of performance of the engine, we found that the swirl ratio which is generated by the inlet should not be too high, but it also is not good with too low swirl ratio. In this investigation, comprehensive consideration of economy and power, the no.1 inlet is selected as the best one for the next study.

With the development of our society, natural resources, environment and population have become more and more important for human beings to live and develop. People started to focus on the “Green” index of products. As a result of that, we should combine environment protection, control and pollutant prevention with the whole process of design and production in mechanical manufacture industries. Additionally, we also should choose the path of sustainable development to improve “Green” index by the rational resources and energy utilization.

This paper presents a current comparator based four-terminal impedance bridge for quantity-value dissemination of national AC resistance standard in China. In order to enhance the feedback adjustment ability and simplify the balance process, the bridge applies a frequency selective amplifier instead of feedforward and feedback networks to balance the magnetomotive force of the current comparator. The resistance difference between the measured and standard resistor can be calculated according to their voltage difference indicated by a digital lock-in amplifier. The AC/DC resistance relative differences between Double Helix Resistor and Tinsley standard resistor are measured with the proposed bridge under 1592Hz.

By adopting CFD numerical simulation software, the transient state numerical simulation of engine is carried on. The intake and compression stroke are studied in maximum power and maximum torque conditions. Through numerical simulation, we can learn the change of TKE with the crank angle, and give a guide for improving design of intake port and chamber. At last, a conclusion is found about the engine that at high speed, the gas flow in cylinder infects the stability of spark ignition.

Being an advantageous combustion technology, flameless combustion is being widely investigated mainly with gaseous fuels for its high efficiency and low pollution. In this paper the realization of liquid flameless combustion in micro turbine environment is investigated. It is indicated that air preheating is not the essential condition to attain flameless mode and the air injection speed is more important to lower the whole reaction rate. Flameless combustion was described in terms of the realization mechanism, flow field, flame shape, temperature, and emissions. Finally the heat transfer model of the recirculated gas applicable to liquid fuel flameless combustion based on the combustor structure is presented.

Boiler steam pressure control system is important because of affecting the turbine speed directly. In engineering, the steam pressure control system is mostly dominated by traditional PID control. But the traditional PID control strategy can’t obtain satisfied control effects with the changing of the fuel and give-wind flow. The use of intelligent control strategy has been studied in recent years in order to improve steam pressure control. In this paper steam pressure control system with adaptive fuzzy PID control is presented, and the simulation results based on MATLAB show that the proposed algorithm can largely improve the system response performance compared to the traditional PID control.

With the development of power systems, the problem of security, stability and economics has become increasingly important. Reliable real-time data base is the foundation of analysis of the systems security and stability. Power system state estimation is used to build reliable real-time model of the power network. It has the on-line security analysis function. Power systems are large, complex systems containing highly nonlinear components. Therefore, traditional approaches often have difficulties in finding the optimal solution efficiently. Artificial intelligence techniques are being applied to a wide range of practical problems in power system. With their ability to some laws of nature and mimic human reasoning, AI techniques such as fuzzy logic and genetic algorithm seem to be more efficient in dealing with large systems and complex problems. Artificial intelligence techniques have been applied in power system applications. This paper presents a method of adaptive genetic algorithm and fuzzy logic applied in phasor measurement placement and bad data identification. And simulation is evaluated on IEEE 22-bus power system.

Steam boiler supplies steam of certain quality in industry process according to the changes of load. It is important of most power plants and has been concerned with analyzing power system dynamics in various works. Drum water level is one of the main processes in the boiler. Because of the phenomenon of false water level, three measurement signals including drum water level, water supply flow and steam flow are introduced. In this paper three impulses Cascade control system with fuzzy PID control is presented, and simulation is performed based on MATLAB.

A vibration reducing system of seismic isolation bearings is introduced into beam string structures. The vibration control on seismic response of beam string structures (BSS) with seismic isolation bearings is discussed. Firstly finite element models for different analyses are established by using explicit dynamic analysis program LS-DYNA. Then the seismic response analyses are performed on a single beam string structure with and without seismic isolation bearings to investigate the effectiveness of the seismic isolation bearings in reducing vibration response of BSS. Furthermore, parametric analyses are conducted to examine the effects of lateral stiffness and damping of the seismic isolation bearings on seismic isolation. The analytical results indicate that the vibration reducing system can effectively reduce the vibration response of BSS against seismic force, and be applied in the vibration control of BSS.

In this paper, the influence of tie beams for piers is investigated on the dynamic characteristics and the seismic performance of a continuous rigid frame bridge with twin-legged piers. Modal analyses and the linear seismic response analyses are performed on a practical continuous rigid frame bridge with twin-legged piers with no tie beam, one tie beam and three tie beams of pier, using software Midas/civil. The findings indicate that installing tie beams of pier can increase the natural frequencies of this kind of bridge. Setting tie beams of pier is disadvantageous to the seismic performance of the bridge beam, but advantageous to improving the seismic performance of the twin-legged piers. The influence of tie beams of pier on the seismic performance on the whole structure is relevant to the pier height. These analytical results provide a reference for the seismic design and analysis of similar structures.

The working principle and driven approach of a piezoelectric linear motor which uses axial stretching vibration of cascading piezoelectric elements is introduced. The prototype of that motor is designed and fabricated. It’s performance is also tested. The motor’s vibrator is a stick and moving object is a cylindrical ring which contacts with vibrating stick in the shape of cylindrical surface. The forward and backward movements of moving object are achieved by utilizing the axial stretching vibration of vibrating stick. The moving direction is altered by changed the frequency of driving signal. The structure of the motor is simple and the power supply is single sine phase. So that it is easy to be smaller. In addition, the thrust force is increased by cylindrical surface contact between moving object and vibrating stick so that it is easy to be practical also. This kind of piezoelectric linear motor is very suitable for precise positioning of objects, fine material handling, and vibration cutting tools.

With the developments of the design theories and the researches, the quantity and the technology of space truss systems in our country have reached the international leading level. In the meantime, the construction methods need to achieve even higher standard. In the article, the rhombic space truss roof of the north station building of Suzhou is selected as the research object. Each step of the sliding and unloading construction is simulated by FEM. The stability and rigidity of the truss are checked in detail. It gives an representative exsample for complicated construction design of large-span space trusses.

Electrical effect induced by the laser plasma was investigated with an external tiny probe during Nd:YAG high-power pulse laser ablation on copper target in air. One equivalent circuit for the electrical effect induced by laser plasma was proposed. Based on the equivalent circuit, a new theoretical explanation of the signal generation mechanism is proposed, and the reason that the distribution of electrical signal wave is strongly dependent on the probe distance was discussed. Further the observed signal peak polarity overturn was explained.

Starting a business is the impetus of the increase and in economy ,and it is also the basic which makes the economy of a nation, a region, or a corporation full of continuable developmental energy. In entrepreneurial society, whether person, social or government maybe the entrepreneurs. Personal entrepreneurship is to create wealth; Social entrepreneurs are to support individuals to create wealth, and to support the formation of entrepreneurial ability and practice; Governmental entrepreneurship is to organize and guide the community to build the Entrepreneurial support systems. In the entrepreneurship, the Government's responsibility is not only to develop the policies of entrepreneurship promotion, but also to build the entrepreneurial support systems. The Government is the first entrepreneurs, that is , the creator of the Entrepreneurial support system.

The modal analysis is performed on the single beam string structure in a practical project in this paper. Then the response history analyses, under the four different earthquake-induced ground motions in the single direction, are implemented on the structure. The analysis results indicate that it is very necessary to install out-of-plane bracings for the single beam string structure. In the design of similar structures, the section dimensions of the struts can be appropriately reduced due to the average stresses of the struts being smaller, and cross beams near the middle of structures are be given attention. And the analysis results provide a reference for the seismic analysis and design of similar structures.

In this paper, taking a practical project for the study, using the finite element analysis software ANSYS, static analyses under different load conditions are performed on a single beam string structure (BSS) and a one-way beam string structure with the cooperation of the supporting structure, respectively. Moreover, influence of factors on mechanical properties of the one-way BSS with the cooperation of the supporting structure is investigated. The factors include grouting, support form, corrosion. The results can provide a reference for design and construction of the same type of structure.

The CrB Particles Reinforced MMC Coating was prepared by using high velocity arc spraying (HVAS) method. Through a series of experiments, including metallographic, SEM and EPMA investigation, the microstructure and composition of the coating were analyzed in details. Additionally, the abrasion resistance mechanism of the coating was studied through field test and observation on the abrasion surface of the coating under the SEM. The results show that the microstructure of the coating is characterized by typical compact laminated structure composed of successive metal matrix and hard particles mainly of borides of chromium and oxides of chromium. The abrasion resistance mechanism of the coating lies in two aspects. One is that the hard particles scatter evenly and dispersedly in the coating, which can reinforce the coating and play a barrier role to hinder the movement of the abrasion particles. The other is that the metal matrix with well ductility and toughness make a buffer action to the impact caused by the abrasion particles, thereby the waste rate of the coating can be greatly slowed down. The results also show that the hardness, shape and quantity of the reinforced particles have magnificent influence on the abrasion resistance of the coating made in this paper.

The coatings for elevated temperature erosion resistance in circulating fluidized bed (CFB) boilers were fabricated by high velocity arc spraying process and CrB powder wire. The microstructure and phase component of the coating were examined by optical microscopy(OM) and Transmission electron microscopy (TEM). The properties including microhardness, adhesion strength and in-situ erosion rate of the coating were measured. The failure mechanism was also discussed based on the experimental data. The OM results showed that the coating consisted of individual flat lamella, thin oxide layer, porosity and very small amount of particle which characterized as different shape and color respectively. TEM results indicated that the phases within the lamella were mainly composed of α phase, amorphous phase and other nanosized particle phase of Fe23(C,B)6, Cr23C6 etc.. The amount of amorphous phase near the substrate was more than that in the other area indicating that the appearance of amorphous phase was related to the high cooling rate of the coating. The microhardness was about 860~1100HV0.2. The coating exhibited high erosion-corrosion resistance, which was about six times as 20G steel. The advantage of the coating with excellent performance, simple process and low cost made it possible to find potential application in power plants.