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This paper presents that the RC polyphase filer has characteristics as a complex analog Hilbert filter. Phase characteristics of the RC polyphase filter have the same as the Hilbert filter. Also its gain characteristics can be approximated as the Hilbert filter; as its order becomes higher, its gain characteristics become closer to the Hilbert filter. We have proved these for 1st to 4th RC polyphase filters, as well as in general n-th order case, and also confirmed with numerical simulations.

A design and simulation for L-shaped slot microstrip line antenna with semicircle defected ground structure has been researched, the main purpose is suppressing the existence of higher order harmonic. In this paper, simulated soft (Ansoft HFSS V.6.0) used to be simulated the frequency response under different parameters such as dimensions, amounts of SDGS. The results show good performance of SDGS in higher resonant frequency suppression. Final, an antenna with 2.4GHz center frequency had been design and fabricated.

A design and simulation for low pass microstrip line filter with defected ground structure has been researched, the main purpose is with the simplest method to design an ideal low pass filter. In this paper, simulated soft (Ansoft HFSS V.6.0) used to be simulated the frequency response under different geometric shape of DGS. The results show good performance of a low pass filter with DGS. Final, a low pass filter with DGS design and fabricated, The properties are shown as flow: center-frequency: 7.28G, S21:-47dB, cut-off frequency: 5.88GHz.

A periodic microstructure with dielectric and metal layers is proposed to obtain a bandpass filter. The multilayer microstructure is compounded of ring cross slot and cross slot. The center frequency of the filter is 0.338THz with a 3dB bandwidth of 75.62GHz. The maximum insertion loss in the pass band reaches 0.60dB. The bandedge transitions of the rejection bands are 232dB/THz and 176dB/THz, respectively. Furthermore, the physical mechanism of near field distribution and the influence of two factors (the number of metal layer and dielectric layer) on the passband have been studied. Meanwhile, the frequency response is analyzed for different incident angles and polarizations. The frequency response characteristic is insensitive to the polarization, and a good performance for incident angle of the transmission is obtained. It can be applied to THz atmospheric communication system.

A simple on-site transmittance measurement setup that is easy to move and install is proposed in this study. It is especially suitable for those cases when laboratory instruments are not applicable. Ordinarily, witness samples are measured since the uniformity is good enough inside the thin film coator and the size of the sample is proper for the facilities to measure. When the spot size of the measuring instrument is too large for the filter or the size of the test sample is too large to fit into the instrument. The proposed setup is shown to work well for this measurement. An application for this setup is also presented. The test target was a stripe filter, which has five band-pass thin films and nominal dimensions of 120 x 3.6 mm each film. Distance between neighboring films is 3.85 mm. The width of each film is so narrow and the size the stripe filter is large such that the traditional method for spectral transmittance is not applicable. The proposed measurement setup consists of a light source, integration sphere and spectrophotometer. The setup was installed inside a dark room. It shows that the setup can provide as accurate results as those data measured by an accreditated instrument. The difference between the present setup and accreditated instrument was found within 7% for high radiance. When the radiance of the incident light is low the accuracy decreases, which can be compensated by stronger light source. In addition, since the measurement spot size is estimated as 1.5 x 2.1 mm it can provide local transmittance data along the stripe thin film rather than a single data represented by the witness sample.

This research proposes technical and economic analysis of harmonic distortion impact and mitigation technique in power networks. Main proposal of research is analysis of harmonic impact and harmonic solution by regarding to economic decency for investment. Parallel resonance is harmonic impact that will be mentioned in this research because it is a problem that is mostly emerged in industries that contain non-linear loads and power factor correction devices. Its impact on power network is high voltage and current amplification, which link to equipment and system failure. An application of detuned filter will be proposed to solve the problem due to its popularity (It is a basic solution, easier and more inexpensive than the other solution). Parallel resonance condition will be modeled with an industrial power network, which contains a power transformer, a non-linear load (AC drive), a power factor correction device (capacitor bank) and a harmonic correction device (detuned filter bank), by using electrical, mathematical and payback period formulas. The results will illustrated the impact of parallel resonance phenomenon due to harmonic distortion in power network.

In light of urgent requirement of onboard ballast water treatment, a novel wall-flow structure porous ceramic filter (PCF) has been applied with combination of UV light in our laboratory works. According to the strict criteria of International Maritime Organization (IMO) on ballast water treatment, removal efficiencies on indicator planktons should be almost 100% even at high initial densities. However, the treatment efficiencies of PCF may be greatly affected by operational conditions of the system. Hence response surface methodology (RSM) was used to evaluate the significance of the operational factors on algal removal efficiencies. Based on our previous works, flow rate, algal density and algal size were considered as three key conditional factors during PCF treatment. These three individual factors and interactive effects between each two facts were studied statistically by Minitab 15. Also, experimental studies were arranged according to full factorial design of a 6L PCF on simulated ballast water treatment at different flow rates, algal densities and algal sizes. By computational prediction and mathematical analysis, the operational conditions were optimized with first order derivation of predicted model. And by doing so, the utmost optimization was estimated to achieve higher performance of PCF system.

Most of the product design on the market is variant design or adaptive design, which need to reuse existing product design knowledge. A key aspect of reusing existing CAD model is correctly define and understand the design intents behind of existing CAD model, and this paper introduces a CAD model annotation system based on design intent. Design intents contained all design information of entire life cycle from modeling, analysis to manufacturing are marked onto the CAD model using PMI module in UG to improve the readability of the CAD model. Second, given the problems such as management difficulties, no filter and retrieval functions, this paper proposes an annotation manager system based on UG redevelopment by filtration, retrieval, grouping and other functions to reduce clutter on the 3D annotations and be convenient for users to view needed all kinds of annotations. Finally, design information is represented both internally within the 3D model and externally on a XML file.

Early design decisions with regard to building facade characteristics play a significant role in the resulting building's thermal performance. In this context, external metal mesh screens -used as a permanent second facade skin- are a rather new shading alternative, particularly in non-residential buildings. It has been suggested that such products can filter excessive incident solar radiation while maintaining the facade’s transparent quality. Given the multifaceted implications of this shading device for building energy performance, we undertook a detailed simulation-based study to evaluate the impact of metal mesh screens on annual energy demand for heating, cooling and electric lighting in different European climate zones. Possible design variations were considered in terms of mesh screen translucency, window to wall ratio and facade orientation. The feasibility of using such a shading strategy to provide passive cooling during summer was also explored, along with suitable ventilation scenarios. Toward this end, we examined a number of existing approaches to simulate metal mesh screens and identified their capabilities and limitations. A typical office space was tested in three European locations, taking local building construction standards into account. The results of this study can help planners in their choice of the appropriate shading strategy and provide recommendations for the application of metal mesh screens according to the climatic and architectural criteria.

For MEMS (Micro-Electro-Mechanical System) inertial sensor low precision, high noise and the characteristics of the gyroscope error accumulating, this paper designed a kind of yaw angle measuring system based on EKF (Extended Kalman Filter) by STM32 microcontroller and MEMS sensor. The EKF applys the attitude angle quaternion as the filter state variable, the angular rate as the filter time update. And application of the carrier location's gravitational field and geomagnetic data, complete filter measurement update, suppress divergent attitude error, obtain high accuracy and reliability of the attitude angle (pitch angle, roll angle, yaw angle) data. Experimental results show that the practical application of error control heading within ± 1º, with high practical value.

The engine air supply system is the main source through which impurities from the atmosphere reach inside the kinematic couplings of the engine. The engine protection is ensured by periodically replacement of the air filters. Determining air filters service life is a difficult problem due to different operation conditions of the vehicles. Therefore, air filters are frequently replaced more often than necessary on the principle that a new filter is better than a replaced one. The present paper aims to determine if the air filters replaced during the preventive maintenance activities have reached the end of their service life or they could still be used. The research is based on measuring the pressure restriction and estimating the mass of dust collected by the air filters.

In this paper, a W-band dual-mode substrate integrated cavity fourth-order band-pass filter is presented, which utilizes LTCC technology. The filter is composed of two dual-mode resonators which are constructed by rows of via arrays in the substrate layer. Two coupling vias near particular diagonal corners are set to perturb the two degenerate modes in each cavity and thus to generate an intra-cavity coupling. The filter exhibits 3dB bandwidth about 2.4GHz, return loss better than 19dB and out of band rejection better than 30dB. The filter occupies the area of 3.752mm4.064mm (including the two feeding lines) in the LTCC substrate.

This paper presents the resonance impact on power factor correction system (PFC system) in power system with harmonic distortion. The main purpose is to show harmonic current amplification that generated by the parallel resonance phenomenon in power system and problem solution. The power system model for analysis consist of the harmonic current source and PFC system. These devices are established by MATHLAB/Simulink. In simulation, the variable speed drive, which is DC drive, instead to the harmonic current source in power system that use capacitor to improve power factor of system. The problem solution, the series reactor, which is detune filter, is used to correct parallel resonance problem, by connecting capacitor with the series reactor, which is detune filter. The result of simulation, detune filter is able to avoid the parallel resonance phenomenon and partially reduce harmonic current that flowing to capacitor, however the series reactor, which is detune filter, is unable to reduce harmonic current of the harmonic current source.

This paper presents the realization of CMOS-based current-mode Elliptic ladder band-pass filter by using doubly terminated Elliptic RLC ladder band-pass filter prototype [1], [2]. The proposed circuit contains lossless integrators, lossy integrators and multiple outputs current gains. The frequency response of the proposed circuit can be electronically tuned between 1 MHz and 100 MHz by adjusting bias current between 1μA and 1,000 μA. The proposed circuit uses 1.5 V power supply and 0.1 W power consumption. The passive elements that contained in the proposed filter are only grounded capacitors without using other passive elements that can make this filter suitable for integrated circuit. PSPICE simulation results are carried out by using TSMC 0.18 μm technology and agreed well with the theory.

In most cases, recycled plastics include lots of impurities that can not be separated in operation steps of separation and washing. Normally, these impurities should be filtrated in extrusion process with filter plate and single or twin screw extruder. In extrusion process, it is easily for impurities to block the holes of filter plate. So how to improve the performance of self-cleaning can be regarded as a very important requirement for design of filter equipment. Based on FEM simulation, this paper discusses mechanism of filter plate’s blocking, the pressure distribution and deformation of two direct flow filtrations. Specially, a side stream filtration including how to clean itself has been introduced.

The aircraft environmental control system (ECS) is a critical aircraft system that provides the appropriate environmental conditions to ensure the safe transport of air passengers and equipment. The functionality and reliability of ECS have elicited an increasing amount of attention in recent years. The heat exchanger is a particularly significant component of ECS because its failure reduces the system’s efficiency and can lead to catastrophic consequences. Health assessment and fault diagnosis for the heat exchanger are necessary to perform maintenance and prevent risks in a timely manner. This paper presents fault-related parameter estimation methods based on strong tracking filter (STF) and logistic regression (LR) algorithm for heat exchanger health assessment and root cause classification, respectively. Heat exchanger fault simulation is conducted to generate performance degradation data, through which the proposed methods are validated. Results demonstrate that the proposed methods are capable of providing stable, effective, and accurate heat exchanger health assessment and root cause classification.

Owing to the dynamic and competitive business environment, manufacturing companies take real-time monitoring and rapid decision making based on RFID applications, which brings huge volume of information and events generated in the defined manufacturing workflows. Complex Event Processing (CEP) is introduced to solve the problems mentioned above. CEP is applied to handle diverse and large amount of low-level multiple data and primitive events for the purpose of identifying meaningful event patterns. It is very important to integrate the CEP technology to the manufacturing workflows. In this paper, we provide a novel framework of RFID-based complex event processing system for assembly manufacturing applications like cars and high-speed trains. It bridges the hardware in workshops and enterprise applications. The Complex Event Management System (CEMS), which is the kernel of the framework, can filter the irrelevant events and work with uncertain data. Furthermore, a concrete example is used to describe the framework and validate the feasibility in assembly monitoring of the car manufacturing.

We selected a typical filter material for high voltage electrostatic filter composite horizontal collector. Air filter can achieve high speed. It cost very low and can endure high temperature resistance. Removal of fine particles of dust effect is good. Solving the complex problems of higher smoke temperature conditions of traditional bag house can not handle, while reducing the dust collector investment cost, promote the development of China's dust remover industry.

In this paper a low-cost Micro-Electro-Mechanical System (MEMS) inertial measurement unit is designed, a 3-axis accelerometer and 3-axis gyroscope simulated 6 degrees of freedom orientation sensing through sensor fusion. By analyzing a simple complimentary filter and a more complex Kalman filter, the outputs of each sensor were combined and took advantage of the benefits of both sensors to improved results. The experimental results demonstrate that the output signal can be corrected suitability by means of the proposed method.

The initial designed structure of the diameter measuring gauge of filter rod forming machine is too large, so that it cannot be installed in the limited space of filter rod forming machine. Because of this, the structure of the diameter measuring gauge is redesigned in order to overcome the space constraints of filter rod forming machine. Firstly, the diameter measuring gauge of KDF2、KDF3 type filter rod forming machine is redesigned by combining the advantages of the theory of inventive problem solving (TRIZ) and constraints (TOC). Next, through constraints theory, finding the main contradictions of initial design and then contradictions can be eliminated by using inventive problem solving theory. Finally, diameter measuring gauge of filter rod forming machine design should be available, and the product design successfully. It is the first time that this type diameter measuring gauge is designed and installed on the KDF2、KDF3 type filter rod forming machine successfully across the country.

As part of studies into the use of Smartphones as solar-radiation monitors, this article characterizes the violet response of a consumer complementary metal oxide semiconductor (CMOS)-based Smartphone image sensor in a controlled laboratory environment, with an adjustable Lamp as a radiation source, a band-pass filter (central wavelength is 400nm) covered on Smartphone camera lens and a ASD spectrometer observing synchronously. It is found that a logarithmic relationship appears between CMOS-based sensor imaging DN values and irradiance, and the red (R) component in the chromo-photograph is linearly relative to irradiance. In addition, a Smartphone can be used as a convenient and low-cost scientific instrument in the field of monitoring radiation characterization, due to its capacity to detect usable irradiances.

In view of the traditional measurement system is not easy to install and design shortcomings, such as volume and requires a lot of wiring, This system used STM32 microprocessor and CC2530 ZigBee wireless technology to achieve the acquisition of High-speed rotating strain, high-speed storage, wireless monitoring system. This system can be used to replace manual operation, make the test more intelligent, more convenient and more accurate. This article used the STM32F103 chips as the main control system chip, implement the collection and storage function, CC2530 ZigBee protocol implemented wireless transmission function. Acquisition module used the high-speed AD transform chip ADS1274, Four-way synchronization acquisition, which convert digital signal transmit to the main control chip, the main control chip collected data which stored in the high capacity SD card. When need data, the system get the data from the SD card by zigbee wireless transmission to the monitor software. This system used the hardware filter and software filter, join the manning window, which reduced the influence of noise and improved the system accuracy. This paper had solved the monitoring question of the high-speed acquisition structure, implemented the function which data collection, storage and remote control for the integration, according to testing, the various technical indexes reach the system requirements[1].

Coal mine roadway advanced detector, including the transmitting and receiving devices, is a kind of geophysical instrument used in coal mine roadway advanced detection based on the dynamic and directional electric field excitation method. The transmitting device emits dual frequency modulated square wave current into the excavation face and the receiving device receives potential difference of coal and rock medium generated by induced polarization, of which the frequency selection circuit is to filter the interference of the harmonics of the signal and other frequency components. The paper derived expressions of emission current. Considering the actual working conditions, the paper proposed the design requirements of the frequency selection circuit and the scheme of a controller to control multiple frequency selection filter circuits. The paper completed the design of the control circuit consisting of a microcontroller and analog switch MAX313 and the band-pass filter circuit consisting of universal active filter UAF42. According to the circuit simulation and the analysis of the data with software of multisim, it proves the design of circuit meets the requirements.

In the process of acceleration dynamic measurement, the measurement results have quite large dynamic errors, due to the resonance of acceleration sensors. Using the system identification theory and combining with the dynamic calibration experimental data of acceleration calibration system based on Hopkinson bar, the dynamic model of the sensor is deduced, the dynamic compensation filter is designed. Simulation results show that the compensation filter can broaden the work band effectively. It improves the system dynamic response speed by nine times and advances the measuring accuracy of the test system.

Precision of filter rod circumference is an important performance index of the cigarette manufacturing. The forming mechanism of filter rod, equipment vibration and other interference factors all lead to fluctuations of precision of filter rod circumference which can affect the precision of the cigarette. The existing KDF2/3 filter rod making machine which has the characteristics of compact structure (small space dimension), high speed (300 m/min) and discrete control of precision of filter rod circumference is the core equipment of filter rod production. This paper puts forward four kinds of online real-time detection schemes on precision of filter rod circumference which are Aomeijia’s many groups of detectors scheme, Keyence’s contour detection scheme, high precision measuring diameter instrument detection scheme using multiple sets of KD series meter and the 360 degrees rotating survey meter. On the basis of extensive analysis and experimental validation, Aomeijia’s four-way diameter measuring instrument scheme is optimal. The scheme applies laser to non-contact high speed scan on key radial diameter size of filter rod which achieves 0.001mm high precision detection.

The paper analysis mean filter, median filter and morphology filter. The paper studied order morphology theory and its filter character. Based on this, the paper proposed multi-scale and multi-structure filter algorithm based on order morphology. The result of simulation shows that the algorithm can not only keep the edge and detail of medical image but also can enhance the contrast of recovery image.

To solve the space dispersion (SD) problem which makes the beam formed deviate from its expected direction in wideband digital array beamforming, a new wideband digital array beamformer (WDBF) is designed by introducing an identical variable fractional delay (VFD) filter on each sensor. The VFD filter is an all-pass filter with an infinite impulse response, thus it requires less filter order compared with finite impulse response filter. Since the VFD designed is suitable within the whole fractional delay range of-0.5 to 0.5 in sampling interval, the new beamformer designed is suitable for any direction without redesigning the fractional delay filter. In this way, the real-time property of the new beamformer is guaranteed. Simulation results show that the VFD deigned in this paper is high in precision. Applying it in the new WDBF, the SD problem is solved and the beam formed approximates the ideal beam very well.

Optimization of microwave filter structure parameter based on traditional learning methods faces problems like long design cycles, complex calculation and sensitive to initial value, and so on. A hybrid trust region algorithm which combine the improved trust region with the advance and retreat method is introduced to the field of optimization of microwave filter structure parameter for the first time. Comparison between the methods based on the traditional trust region method and the improved trust region method reveals that the algorithm can significantly increase precision and speed of optimization model of the microwave cavity filter parameters.

A technique for a reconditioning equalizer filter for non-constant envelope signals is described. The input to a transmitter chain is modified by a reconditioning equalizer filter, prior to being applied to the transmitter. The reconditioning equalizer filter modifies and smoothens the amplitude of the signal. The modified and smoothened signal has its peaks reduced which results in lower Crest Factor. The input to the reconditioning equalizer filter could be a baseband, intermediate frequency (IF) or radio frequency (RF) signal. When the signal is an IF or RF signal, it needs to be down-converted to baseband before being applied to the reconditioning equalizer filter. The reconditioning equalizer filter could be performed in a digital or analog domain.

A filter/guidance simulation toolbox based on Matlab software was designed. Built under the principle of “define once and use many times”, the propose toolbox successfully separate the estimation algorithms, the guidance law, and the math model under investigation into three different yet related parts, which drastically reduced the burden of repeatedly designing the same filters and guidance law for different simulation models. Typical example from both simulation cases and real field test data proved the correctness and effectiveness of the proposed toolbox.

The paper deals with the improvement of quality control system harmonic drive with servo applying the method of compensation torque oscillations. The method consists of applying the rejection block. Post documents the oscillatory nature of the system servo-harmonic transmission. Described the reduction block connected to this system suppresses the oscillation of torque, speed and position of the harmonic drive output shaft thereby improving the quality of the regulatory process.The papers solves the problem of torque oscillations of the system which consist of servomotor and harmonic drive. Described rejection filter connected to the input of the system damps oscillations and increases the quality of control.

Automatic segmentation of the line-like regions plays a very important role in the automatic recognition system, such as automatic cracks recognition in X-ray images, automatic vessels segmentation in CT images. In order to automatically segment line-like regions in the X-ray/CT images, this paper presents a robust line filter based on the local gray level variation and multiscale analysis. The proposed line filter makes usage of the local gray level and its local variation to enhance line-like regions in the X-ray/CT image, which can well overcome the problems of the image noises and non-uniform intensity of the images. For detecting various sizes of line-like regions, an image pyramid is constructed based on different neighboring distances, which enables the proposed filter to analyze different sizes of regions independently. Experimental results showed that the proposed line filter can well segment various sizes of line-like regions in the X-ray/CT images, which are with image noises and non-uniform intensity problems.

For the defect Guizhou-Guangdong II ± 500kV HVDC System can not configure filter in accordance with the voltage-mode, which may lead to excessive voltage of AC system, even appear cutting filter due to AC voltage limiting. This paper presents a power adjusting strategy in the process of voltage recovering, based on the character that consume of reactive power converter valve changes with DC voltage. With dynamic functional test and system test, the strategy cuts filter rationally, solving the overvoltage problem of AC system in the process of voltage recovering. It also simplifies the reactive power control strategy.

This paper introduced the structure and special property with type device, analyzed how to realized programmable analogue function module with digital potentiometer. This paper gave a design example of programmable second-order active low pass filter by using digital potentiometer. The programmable filter can be application to the signal filter processing of data acquisition systems. This paper has reference value of theory and practice on the application of digital potentiometer

Electrochemical Machining is one of established non-traditional machining process which is widely used in micro machining parts. Purpose of this research paper is to investigate effect of Electrochemical Machining under low voltage and relatively high current rating on concentrated or masked work piece of Copper and Carbon Steel EN9. Developing Machine set up with the help of PLC and SCADA device for Accurate Positioning and reliable data supervising which includes ECM, basic working principle of ECM, selection and development of components, implementation and to analyze the effect of change in the parameters of the process. Selection and development part will cover design of frame, fixture, pump, filter, tool, electrolyte, and work piece material as a mechanical part, selection of electric drive system and PLC. PLC programming and hardware circuit as electrical and programming part.

In order to solve the problem of detecting harmonic and reactive currents of single-phase APF, the paper gives a detection method for real time harmonic current and reactive current. In the paper, it makes use of some characteristics of triangle function, and calculates the amplitude of active and reactive component from load current. Then the DC component can be extracted by using a low-pass filter, namely the required active component and reactive component. This paper analyzes the characteristics of two kinds of low pass filter, and selects the superior performance moving average filter for experiment. The paper introduces the design of the software and hardware process. The circuit configuration of the proposed approach used in the single-phase system is simple, its dynamic response speed is fast and its detection precision is high. The result of the experiment shows that the proposed approach is feasible and valid.

The cross coupled microwave filter is widely used in the communication sub system .The synthesis of the cross coupled filter is from prescribed transmission zeros and return loss till the attainment of the coupling matrix of each cavity. A compact narrowband combline high rejection filter with cross coupled is presented. A configureiton using identical resonator post with capacitance-loading is introduced. Tested results show that with order-8 filter center frequency at 2017.5MHz, return loss lower than-25dB can be achieved over a relative bandwidth of 1.29%. A sample filter has been fabricated and tested result confirmed the theory result.

This paper first introduces PAC dosing system, then research the feasibility of the project goal. confirmed the goal can be achieved. Research on the project, and analysis the process of this project, and implementation finally. After the PAC dosing filter automatic cleaning device completed, control charts are used to verify the device, results show that, PAC amount is controlled in the range of 1.8~2.2mg/L, COD is above 35mg/L.

In this paper we present a coaxial filter analysis software based on MATLAB. Our software can obtain scattering parameters’ curve of the filter which is composed of high-low impedance coaxial cables. In order to obtain scattering parameters’ curve, we introduce a method of making distributed parameters equivalent to lumped parameters and adopt A parameter matrix approach to get it. Our software has taken into account the influence of step capacitances. Compared with the commercial software HFSS, our software has advantages of strong pertinence, operating fast and easy to adjust. Finally, we use HFSS to validate the correctness of our software.

Physics package is the core of rubidium atomic frequency standards (RAFS). In this paper, a physics package of RAFS with enhanced performance is reported. The physics package is designed according to the separated filter scheme, in which an optical filter and a magnetron microwave cavity are used to reduce the white frequency noise and to intensify the resonance signal. The light-shift (LS) and temperature coefficient (TC) can be conveniently adjusted in the separated filter scheme. A preliminary test shows that a frequency stability of the RAFS is less than .

In this paper we use matrix characteristic value extraction to improve the mathematical model of embedded multimedia information transmission, combined with the characteristic value filter, establish the optimum path model of embedded multimedia information search. By using VC program and data interface function, we directly embed the business English multimedia teaching content into the MATLAB GUI graphical interface, which realizes the button rapid link and ensures the fluency and accuracy of the English translation graphics teaching platform. Finally we test the performance of business English translation teaching platform based on multimedia graphical teaching. From the overall evaluation of students' achievement, multimedia teaching platform has a good teaching effect. It provides the theoretical reference for the study on business English translation talents cultivation.

Dynamic Voltage Compensator (DVR) is able to handle the dynamic power quality problems in distribution network, such as voltage sags and voltage unbalance, and the parameters of the output filter will have important affect on the compensation results. In this paper, the parameter design method of the output filter of a cascaded H-bridge based DVR applied in medium-voltage distribution grid is studied. Through the analysis of the case when filter inductor current has the maximum value, the theoretical expression of the relationship between the low limit of the value of filter inductor and the capability of voltage compensation and power factor is derived. Meanwhile, the method of selecting the filter capacitor value is ​​obtained. The realization of the proposed method are given by taking an engineering project as an example, the correctness and validity of the design method of filter parameters proposed in this paper are verified by simulation.

In this paper a novel filter structure which can be used to find the zero point of the sensorless back-emf of BLDC is proposed. The back-emf amplifier circuit applied this structure is a kind of analog and digital mixed type. It can improved sensorless performance under low speed situation greatly. At last the production and experiments were carried out based on the 100W BLDC driver system. The applicability of the proposed structure was also verified

This paper presents a new control method of a parallel active power filters based on improved harmonic isolation with hardware implementation. The harmonic isolator is based on High Selectivity Filters (it can be tuned at any frequency) and the current control technique consists in a modulated hysteresis current controller. This active filter is intended for harmonic compensation of a diode rectifier feeding a RL load. The study of the active filter control is divided in two parts. The first part deals with the harmonic isolator which generates the harmonic reference currents and is implemented into a DSPACE DS1104 prototyping card. The second part focuses on the generation of the switching pattern of the IGBTs of the inverter by the modulated hysteresis current controller, implemented into an analogue card. The use of High Selectivity Filters instead of classical extraction filters allows extracting directly the voltage and current fundamental components in the α-β axis at high performances. The effectiveness of the new proposed method is verified by computer simulation and by experimental study.

A high efficiency rectifying antenna (rectenna) is designed at 5.8 GHz by using defected ground structure (DGS) filters for low-power energy transfer. A slot-coupled patch antenna is used as a receiving antenna with a high gain of 8.2dB. A DGS low-pass filter at the input port of the rectifying circuit is used to suppress the high order harmonics by 20dB. A DGS dc-pass filter is designed to block the AC signal from transmitting to the load. Both of the antenna and the filters are simulated by the full wave EM analysis software of HFSS. The RF-DC conversion efficiency of 51.8% is obtained when the received power is as low as 3mW.

A new fast design method for active filter is proposed which is different from the conventional ones, as the conventional methods such as the application of manual calculation tends to be time-consuming, complex and pone to error in determination of active filter’s transfer function, also the application of table look-up can only apply to the filter of limited order less than 10. This fast method is illustrated in detail by a practical example of high pass filter. First, transfer function can be rapidly calculated in MATLAB, then the filter circuit performance simulation is presented through EDA, the results show that the proposed method enhances the efficiency of the design as it is fast, precise and direct, what’s more, the fast method is of practical guiding significance to active filter’s design, especially for high order ones.

This article discussed the basic theory and routes for preparing soda-lime-silicate glass by filter mud in beet sugar refinery. The proportion of raw materials and processing conditions were optimized.The research shows that amber glass and green-white glass prepared can meet national standards and the technology was reliable, easy, high benefit both on economical and social effects and without secondary waste .

This paper built 5 KVA / 400 Hz medium frequency power supply AC - DC - AC main circuit, Output filter is designed in detail. Based on SPWM control strategy and the voltage RMS feedback loop and PI adjustment, the Matlab/Simulink simulation model is established, and Harmonics are analyzed, the conclusion is obtained.

The design uses silicon-AlN thin films as the piezoelectric substrate, Use apo- dization weighting methods to optimize the design of IDT. The improved δ function model was Modeling Tools of Apodization weighted ellipse IDT structure, According to the result of simulation, we designed a layout of SAW band-pass filter and fabricated a sample of it which center frequency is 300MHz and insertion loss is 7dB, The research shows the consistency of simulation results with the experimental results.

Keyword extraction is important for information retrieval. This paper gave a hybrid keyword extraction method based on TF and semantic strategies for Chinese document. A new word finding method was proposed to find the new word not exist in the dictionary. Moreover the semantic strategies were introduced to filter the dependent words and remove the synonyms. Experimental results show that the proposed method can improve the accuracy and performance of keyword extraction.