Earticle

The effects of the cutting parameters on the surface roughness in machining the Ni-base superalloy GH3039 were investigated. The experimental design for surface roughness was conducted in this paper based on Taguchi’s experimental. The effects of cutting parameters on surface roughness were evaluated and the optimum cutting conditions for minimizing the surface roughness were determined. The response surface methodology (RSM) was set up between the cutting parameters and surface roughness. The experimental results revealed that the feed rate is the main factor to affect surface roughness, followed by the cutting speed. The prediction of surface roughness and measured surface roughness are fairly close, which indicates that RSM model of surface roughness in machining the Ni-Base superalloy GH3039 is proved to be correct.

White light-emitting diodes (LEDs) are used as a light source in many liquid-crystal displays (LCDs), with blue light generated as a spectral distribution characteristic of white LEDs being potentially harmful to the human retina. We propose a method for reducing the blue light only by calibration and profiling without adjusting. Specifically, this paper attempted to verify the efficacy of colourimetric characterisation for reducing or controlling the blue light. Based on the test results of LCD monitors that use a variety of LED light sources, the white LED exhibited maximal blue light emission at 450 nm, and using colourimetric characterization reduced this emission by ~36%. The proposed method is a novel approach for examining the relationship between display technologies and the human retina.

In the most industrial processes, products are weighed in motion using dynamic weighing systems before the measurement has taken place. There are many kinds of influence factors that affect weighing process. The accuracy of measurement and speed of dynamic response is closely related to the performance of the dynamic weighing system, which are contradictory each other. It is necessary to address these impacts on dynamic weighing system. To compensate affection caused by these factors, an improved adaptive dynamic state estimation (ADSE) algorithm running on the controller of dynamic weighing system for a gravimetric filling machine is proposed in this paper. The ADSE algorithm regards the weighing process as a finite state that controls state migration by estimating the next state of measurement and dynamic compensation for in-flight material. Compared with static compensation algorithm and dynamic compensation algorithm, the results showed that ADSE algorithm can provide accurate measurement and excellent dynamic response.

Fiber optical current sensors based on Faraday effect have a lot of advantages over conventional current sensors and have been studied extensively. To eliminate the vibration sensitivity, a light path of reflective fiber optic current sensor improved is proposed, which makes discharge of Sagnac effect with Sagnac effect itself and do not disturb Faraday Effect at all. The reliability of the system was simulated, then the polarization states for the key optical components of the lights spreading in the improved light path are analyzed with Jones matrix. The results shows that the output of the improved sensor is accordance with the actual case. A new solution for guarantee the term running of fiber-optic current transformer was provided, a feasible method for the practical use of Sagnac fiber-optic current sensor is provided.

In this paper we have aimed to have an energy efficient digital clock design. Digital clock is a type of clock that displays time digitally. The code has been implemented in Xilinx ISE Design Suite 14.2 and results were tested on 28nm FPGA platform using Kintex-7 FPGA family using different SSTL IOStandards. Comparison between different SSTL IOStandard has been done to achieve minimum IO power. Via SSTL technology, we achieve green computing with respect to low voltage impedance. In this work we are testing our digital clock design with different SSTL IOStandards such as SSTL15, SSTL18_II, SSTL135, SSTL12, SSTL18_I. In this work we have taken constant value of air flow and heat sink. Airflow has been kept 250 LFM and medium Heat sink. The design consists of five inputs and six outputs. At th end we concluded that there is 24-35% saving in total power dissipation with 1.2 GHz when compared with 2.2 GHz.

Gesture Controlled Robot is a robot that can be moved according to our limb movements. All we need to do is just wear a gesture device which consists of a sensor such as accelerometer. The sensor mounted on your hand will judge the movement of hand in a particular direction which will result in the movement of the robot in the direction of the hand movement. In this era of modern technology, technology has decreased working hours and has made complicated operations more effortless. Robotics is a very vast field that has helped us make some wonderful machines that assist us in our daily lives or even commercially. Typical industrial robots usually perform tasks that are difficult, dangerous, too complex or dull. They lift heavy weights, and a lot of manual work such as welding can be done using robots. They can perform the same course of action in lesser time with more accuracy. This robotic arm is focused on developing a device by interfacing the hardware with software and creating something which makes the performance of complicated activities comfortable. Though the working of a robotic arm is very simplified, the implementation of this arm requires a good knowledge of Engineering Mechanics, Arduino platform, Electronics Devices mainly sensors and Embedded Systems as well.

Micro-grid control is the key technology in the process of accessing micro-grid into regular grid. This paper summarizes several ways on coordination control in micro-grid and introduces some domestic researches on micro-grid control strategies. It is written on the basis of the achievements on micro-grid control in some developed countries and current situations on domestic micro-grid control. Firstly, the paper introduces the objects of micro-grid control study and describes the control processes of each object thoroughly on different micro-grid control structures. Then the paper states the researches among the world on micro-grid control generally. In the end, the paper discusses the research orientation on micro-grid control which based on the existing problems of micro-grid control and current situations on regular grid.

With the rapid development of P2P technology, P2P IPTV applications have received more and more attention. And program-list distribution is very important to P2P IPTV applications. In order to collect IPTV program information, a distributed multi-protocol crawler was proposed based on principle of program-list distribution. The IPTV programs information will be used for characteristic analyses of program and for automatic sorting of program and establishment of IPTV repository in next work. In addition, a task scheduling model based on fuzzy control is introduced to improve performance of the crawler. In the experiment, three task scheduling algorithms are compared, and the results show that the fuzzy algorithm can balance service nodes’ load effectively with less task execution time.

Making pure rolling shear as the target, based on the principles analysis of shear mechanism in the rolling shear, trajectories of the overlap and the horizontal displacement of the upper blade during the cutting process are directly calculated out. And then the trajectories are optimized with improved natural selection-based particle swarm optimization algorithm (selPSO) deemed lengths of the key rods as variables. On this basis, motion laws of the driving links are reversely worked out through solving position equations of the rolling shear’s mechanism, which are nonlinear equations, with selPSO. The calculated results show that the synthetic horizontal translation (mean value of all horizontal displacement relating to calculated points) of the upper blade reduced by 34.96% and the overlap becomes a constant, which can realize the pure rolling cutting very well and improve the shear quality of the steel plate; selPSO is applicable to solve nonlinear equations in the project, which can overcome the problem of high sensitivity to initial value and improve the computational efficiency.

With the further development of production, a higher request to the measurement of straight2line long displacement has been put forward. This article introduces one technique sayings mechanical contact wheel based on Hall components to measure straight line long displacement. This method directly takes movement part oneself as static reference datum, converting two objects relative movement to the rotation of wheel. The Hall components detect t he rotation angle and the direction of roll wheel, t hen t he displacement is calculated. The measuring technique has many merits, such as simple and small measuring structure, large measuring range, broaden adoption environment and so on, so having certain application value.

Synchronized switch damping (SSD) techniques have recently been developed, as an alternative to active vibration control techniques, to address the problem of structure vibration control. In these techniques, a piezoelectric patch is bonded on the vibrating structure and shunted by a network of electrical elements. During the structure motion, the piezoelectric patch is connected and disconnected from the shunt circuit, according to the displacement extremum, through switching action controlled by a digital signal processing system. Thus the voltage in the piezoelectric patch is enhanced and time shifted in the time domain from the displacement of the vibrating structure. This voltage when shunted through electrical circuit results in increased energy dissipation with enhanced damping effect. This paper proposes to further increase the dissipated energy through a new technique called the synchronized switch damping on negative capacitance and voltage sources (SSDNCV). The idea is to further increase the value of voltage in the piezoelectric patch though the use of negative capacitance and two extra voltage sources in the shunt circuit. First theoretical expressions are derived for SSDNCV method to determine the maximum energy dissipated from the shunt circuit and the corresponding maximum damping. The effectiveness of SSDNCV method, as compared to the previous SSD methods, is then demonstrated in the first resonance mode control of a cantilever beam containing piezoelectric patch. The SSDNCV control reduced the vibration amplitude by 82 % as compared to 63 % and 29 % obtained from SSDNCI and SSDV controls respectively.

In this paper the function of PPL and the principle of measuring frequency were introduced, as meanwhile, the references for the design of PPL based on software was provided. Based on this, we proposed the function of PPL based on software using MATLAB. Because PPL could be affected by different parameters, we analyzed the system in different condition. According to the results, the method of phase locking and tracing C-W pulses using PPL was proposed. We reached our goal that C-W pulses can be phase locked and traced.

123I is radiopharmaceuticals to diagnose thyroid cancer and can be obtained through nuclear reaction by irradiating proton beam (30MeV, 100uA) onto 124Xe gas target in order to produce this medicine. More medicine can be produced under the same condition by irradiation of higher beam current in nuclear reaction energy. However, the higher the beam current is, the more heat is generated and target device may melt. This paper predicts whether production is possible at a higher beam current through heat analysis with modeling of 124Xe target device which is gas target. Geometrical structure modeling was used by 3D CAD SolidWorks and analyzed by using COMSOL. We used modeling in spiral way which is a more spacious surface to increase cooling efficiency of cooling water. We analyzed by simulation that target isn’t melted when the beam output of cyclotron 30 is irradiated onto gas target.

Straight-powered for big users and self-generation power plants are the important measures to promote the electricity market reform in China. However, on the one hand, straight-powered for big users may carry some impacts on the management of power Grid Corporation, such as cost, revenue, etc. On the other hand, self-generation power plants will directly reduce the electricity sales of power Grid Corporation, which affects the operating income accordingly. Through analyzing the composition of income in power grid corporation, two models measuring the impacts on operating income after implementing straight-powered or self-generation are put forward. Meanwhile, an empirical study on the operating income effects of a power grid corporation is presented. The results show that straight-powered for big users and self-generation power plants make the corporation lose 0.00152 yuan per kWh and 0.02 yuan per kWh, respectively. Obviously, the impact of implementing self-generation power plant is greater.

The coal and gas outburst is one of complex geological disasters and its prediction is influenced by a multiple of factors, such as coal gas, ground stress, physical and mechanical properties, and complex non-linear system, which cause the low prediction accuracy. It is a favorable scheme to use the nonlinear BP neural network for the prediction algorithm design. But, the traditional BP neural network algorithm has some defects, such as the slow convergence speed and falling into the local minimum value easily. In order to remedy the defects and improve the prediction accuracy of the coal and gas outburst effectively, the improved BP neural network prediction algorithm of the coal and gas outburst is put forward in this paper. The additional momentum is adopted to adjust the network weight and to speed up the network convergence speed, and then the speed of network learning is adjusted self-adaptively and the number of iterations is reduced. Finally, the simulation of prediction of the coal and gas outburst in mine is carried out. Compared with the traditional BP neural network, the improved algorithm shows its superiorities and provides the basis for the accurate prediction of coal mine disasters.

The negative-sequence eddy current field of the first AP1000 third-generation 1,250 MVA nuclear half-speed (4-pole) turbo-generator is deeply researched in this paper. In order to find out the influence rules of using different rotor slot wedge materials, the eddy current loss densities, which are generated by negative-sequence current, are compared and analyzed. It is well known that aluminium and aluminum-bronze are widespread materials in electric machine industry. Hence, the two materials are adopted respectively as the slot wedge material, the eddy current loss calculations of slot wedges, rotor teeth and damping bars are given, and the loss characteristic analysis results are also obtained in this work. The calculation and analysis results indicate that different materials have different effects on eddy current loss, especially for the loss density of slot wedges, eddy current loss density of the big tooth area is bigger than the small tooth, and damping bars have the biggest loss density on the rotor surface, which all should be attached importance to in actual large capacity generator design.

In this paper, a model of a bearingless permanent magnet synchronous motor (BPMSM) is proposed, the expressions of radial suspension forces are derived, and an accurate model is established. Furthermore, decoupling and basic linearization are carried out for the radial suspension forces using the theory of differential geometry, and a sliding mode controller with fractional order based on a neural network is designed for the decoupled, pseudo-linear subsystem. Finally, a simulation experiment is conducted for the designed control system and the feasibility of this decoupling control approach is validated. The simulation results indicate that the application of the proposed control scheme to a bearingless permanent magnet synchronous motor modeled using differential geometry can achieve steady and independent control of radial suspension forces.

At the present, due to intensified awareness of environmental protection and petroleum resources running low in the world, it is urgent to develop a engine of technical performance with manifold excellent. Aiming at the existing drawbacks of the reciprocating piston engines and the triangle rotor engine, A new kind of engine with simple, novel institution, special principle, low power consumption, low emission, low noise and low cost is designed, sometimes called " Rotary engine " for short. Through computer virtual simulation technology, the scientific rationality of collaborative work in different structures and the novelty of working principles are verified. It lay foundation for development of highly efficient energy-saving engine in the furture.

This study aims to design for an application for the Gas Safety field workers. At first, we did a research on the features and nature of the gas safety field work and its workers in order to draw the requirements for creating the basic contents, and then conducted a survey on the image preference of the workers that could best convey the contents.

According to the scale-free phenomenon of Internet and the puzzle of semantic web, we study UCL-based broadcast control technology under complementary architecture network, introduce the concept of complementary architecture network and UCL, propose UCL-based sharing-distributing system structure for web data under complementary architecture network, mainly analyze the key technologies of broadcast control based on UCL under complementary architecture network, describe the system architecture design, main implementation methods and algorithms of UCL-based super master database and UCL standard data integrated broadcast control platform, and implement a UCL-based integrated broadcast control prototype system, proving and testing feasibility and availability of integrated broadcast control platform proposed in this paper. Therefore, a complete broadcast control platform has been initially established, laying solid foundation for further researches.

In this paper, proposed a new lighting control system which can reduce power consumption compared to conventional street lamps and intelligently control the light efficiently depending on whether there is a vehicle on the street. The new lighting control system proposed by this paper detects the presence of cars by collecting and analyzing sounds generated by the movement of cars. Then, the system controls lighting of street lamps based on the above car detection information, and turns on the street lamps sequentially by transmitting the car detection information. Experimental results showed that lightings were controlled based on the presence of cars and that operations of the lamps were made by turning on the lights sequentially by determining the moving direction of cars. This system is considered a technology that can reduce energies by applying to local roads with a few cars moving or national highways where lights are always turned on with low energy efficiency.

The successful application of short electric arc machining (SEAM) technology can solve the long-standing technical problem of hard-facing materials processing which machinery manufacturing industry generally faces. In the article, we trained high power supply neural network model by using the simulation data. And on this basis, we optimize parameters of power supply combined with genetic algorithm based on objective weighting method to guide parameters changes to meet the requirements. The results, by analyzing startup test and load-mutation test, show that the power supply have the advantages of stable output voltage and fast response speed, which meet the expectant targets and machining requirements. At last, through cutting experiment of SEAM on nickel-based superalloy, the power supply of SEAM designed by this new method is verified that its electric properties meet processing requirements of SEAM.

A study of a fractal structure of a clock generator and distributor is performed with possible use in today’s ultra-high-speed, GHz range or higher, integrated circuit design and other future digital system applications. A fractal cell is composed of a simple ring oscillator with three inverting amplifiers, configuring a triangle shape, with an inverting amplifier placed at each side. Each side is then shared with an adjacent cell, which makes this fractal structure that is, theoretically, spreadable infinitely in 2D domain. This fractal structure is proved to have insensitivities to supply voltage and temperature variations: less than 1% of clocks skew of a clock period, with given 3% of supply voltage or 5% of temperature fluctuations. This is because any local disturbances or gradients will instantly and evenly be distributed to the whole networks yielding a global averaged state change. SPICE simulations are done with 0.5μm, 3V, N-Well CMOS process technology in order to prove the validity of the idea. A simple fractal CMOS layout, with 108 inverters, is also performed and included for future chip measurement.

To improve the monitoring accuracy of the crop nitrogen sensor, this paper systematically investigated the optical system parameters affecting the monitoring accuracy of the monitor by analyzing principle of the sensor and the optical system design scheme, and designed a scheme of calibrating optical system parameters which included calibration of single photocell, multi-element combination and integrated optical system. Besides, the parameters calibration of optical system was further conducted by laboratory experiment. The data of rice field experiments were used to validate the effectiveness of the parameter calibration scheme of the optical system. The results indicate that the determination coefficient between normalized difference vegetation index (NDVI) and nitrogen content of rice leaves increases to 0.734 from originally 0.651. That is, the monitoring performance improves significantly after performing system calibration.

H. 264 / AVC is a kind of newest video standards, the use of all kinds of complex forecasting mechanism, makes the compression ratio greatly to ascend, which provides a reliable algorithm support for high-definition video real-time transmission. In this paper, in order to balance boundary treatment of data dependency relationship and macro block filtering the speed of contradictions, a kind of H.264 to block filter hardware structure in SMIC0 was proposed. Under the library 0.13μm CMOS, the comprehensive results show that the circuit in the 300 MHZ clock frequency consumption 40000 logic gates, which needs 64 clocks cycle to deal with a 16 x16 macro block.

In this study, a control algorithm is proposed to enhance the braking performance for an Autonomous Emergency Braking (AEB) system by improving the method for calculating the brake-application time when the vehicle is on an incline. The conventional AEB system in an algorithm-applied vehicle is limited because the gradient is not considered. With such systems, only a flat road environment is considered in terms of the road settings. To improve the braking performance on an incline, an AEB algorithm considering the road gradient is developed. A new calculation method for the brake-application time is proposed on the basis of the maximum deceleration that a vehicle can obtain on a road, and this is done by analyzing the force exerted on a vehicle that is on an incline. We confirmed that the AEB algorithm proposed in this paper improves the braking performance compared to the conventional AEB algorithm.

At present, embedded system development establishes embedded component model (ECM) with informal and unstructured methods, and the dependencies among components are implicit and lack rigorous semantic. This paper presents a formal model for specification, verification, and composition of embedded system. In this paper, we provide a rigorous and compact description of the modeling elements of ECM and define component combination operations based on formal semantics which is feasible and effective both theoretically and practically. The corresponding techniques such as component property, connection constraints and ECM hierarchy are also discussed in this paper. Based on this model, DTSED component production toolkit is developed as the support platform for the ECM. Finally, a case study is introduced to explain how the above ECM can be used.

Short-term load forecast plays an important role in the safe and economic operation of power system. Its prediction accuracy affects the power system's security, profit and quality directly. And meteorological factor is one of the key factors that affect the accuracy of load forecasting. In this paper, we put forward enterprise electric load forecasting method combined with grey relational degree algorithm and multivariate linear regression forecasting method. The example shows that this method can get better prediction accuracy.