Search | Engineering

订阅投稿

首页工程期刊工程焦点工程成就工程前沿关于我们 English

资源类型

期刊论文 167

年份

2023 24

2022 16

2021 17

2020 12

2019 11

2018 7

2017 4

2016 4

2015 7

2014 3

2013 5

2012 8

2011 1

2010 7

2009 4

2008 6

2007 10

2006 5

2005 1

2004 2

展开︾

关键词

自动驾驶 3

扫描格式转换 2

移动边缘计算 2

边缘计算 2

驱动因素 2

21世纪海上丝绸之路 1

5G 1

AQAM 1

CO₂排放 1

Car-to-X 通信系统 1

IEEE 2030.5 1

PCB缺陷检测 1

PTCNN 1

VO₂薄膜 1

Z箍缩 1

“互联网+”智能交通 1

中华自然理念 1

中国聚变工程实验堆 1

中子测量 1

展开︾

检索范围：

排序：展示方式：

A driving pulse edge modulation technique and its complex programming logic devices implementation

Xiao CHEN,Dong-chang QU,Yong GUO,Guo-zhu CHEN

《信息与电子工程前沿（英文）》 2015年第16卷第12期页码 1088-1098 doi: 10.1631/FITEE.1500111

摘要： With the continual increase in switching speed and rating of power semiconductors, the switching voltage spike becomes a serious problem. This paper describes a new technique of driving pulse edge modulation for insulated gate bipolar transistors (IGBTs). By modulating the density and width of the pulse trains, without regulating the hardware circuit, the slope of the gate driving voltage is controlled to change the switching speed. This technique is used in the driving circuit based on complex programmable logic devices (CPLDs), and the switching voltage spike of IGBTs can be restrained through software, which is easier and more flexible to adjust. Experimental results demonstrate the effectiveness and practicability of the proposed method.

关键词： Driving pulse edge modulation Switching voltage spike Complex programmable logic device (CPLD) Active gate drive

HTML PDF 收藏

Analysis and design of pulse frequency modulation dielectric barrier discharge for low power applications

Tang-tang GUO,Xing-liang LIU,Shi-qiang HAO,Chi ZHANG,Xiang-ning HE

《信息与电子工程前沿（英文）》 2015年第16卷第3期页码 249-258 doi: 10.1631/FITEE.1400185

摘要： For low power dielectric barrier discharge (DBD) used in small-size material treatment or portable devices, highstep transformer parasitic capacitance greatly influences the performance of the resonant converter as it is of the same order of magnitude as the equivalent capacitance of DBD load. In this paper, steady-state analysis of the low power DBD is presented, considering the inevitable parasitic capacitance of the high-step transformer. The rectifier-compensated first harmonic approximation (RCFHA) is applied to linearize the equivalent load circuit of DBD at low frequency and the derived expressions are accurate and convenient for the analysis and design of the power supply. Based on the proposed linear equivalent load circuit, the influence of transformer parasitic capacitance on the key parameters, including the frequency range and the applied electrode voltage, is discussed when the power is regulated with pulse frequency modulation (PFM). Also, a design procedure is presented based on the derived expressions. A prototype is constructed according to the design results and the accuracy of the design is verified by experimental results.

关键词： Dielectric barrier discharge Rectifier-compensated first harmonic approximation Parasitic capacitance Power converter design

HTML PDF 收藏

Frequency-controlable sine signal based on PWM and its implementation on FPGA

Lianzhen HUANG, Jiangang LI, Dongjun ZHANG

《机械工程前沿（英文）》 2012年第7卷第3期页码 322-328 doi: 10.1007/s11465-012-0312-9

摘要：

A sine generation method that the different frequent sine signals can be generated by the different Pulse-Width Modulation (PWM) signals generated by Field-Programmable Gate Array (FPGA) through low-pass filter of fixed parameters was proposed. The method just takes a few FPGA resources and was proved feasible by the theory. The experiment results and theory analysis tally.

关键词： Pulse-Width Modulation (PWM) Field-Programmable Gate Array (FPGA) frequency controllable

HTML PDF 收藏

Toward a nonlinear control of an AC-DC-PWM converter dedicated to induction heating

Amel HADRI-HAMIDA, S. ZEROUALI, A. ALLAG

《能源前沿（英文）》 2013年第7卷第2期页码 140-145 doi: 10.1007/s11708-013-0243-0

摘要： In this paper, a nonlinear control strategy applied to an AC-DC-pulse width modulation (PWM) converter is developed and simulated. First a nonlinear system modeling is derived with state variables of the input current and the output voltage by using power balance of the input and output. The system is linearized and decoupled, and then a state feedback law is obtained. For robust control of parameter perturbation, integrators are added to the exact feedback control law. The simulation is provided to verify the validity of the control algorithm.

关键词： DC-DC converter AC-DC-pulse width modulation (PWM) converter induction heating nonlinear control

HTML PDF 收藏

采用内嵌时钟控制技术的低功耗双边沿隐形脉冲触发器 Article

Liang GENG,Ji-zhong SHEN,Cong-yuan XU

《信息与电子工程前沿（英文）》 2016年第17卷第9期页码 962-972 doi: 10.1631/FITEE.1500293

摘要：概要：本文提出了一种新颖的采用内嵌时钟控制技术的双边沿隐形脉冲触发器（dual-edge implicit pulse-triggered flip-flop with an embedded clock-gating

关键词：低功耗；触发器；隐性；时钟控制技术；双边沿

HTML PDF 收藏

Simulation of grid connection and maximum power point tracking control of brushless doubly-fed generator in wind power system

Hicham SERHOUD, Djilani BENATTOUS

《能源前沿（英文）》 2013年第7卷第3期页码 380-387 doi: 10.1007/s11708-013-0252-z

摘要： In this paper, based on the analysis of the mathematical model in a common synchronous reference frame of the brushless doubly-fed generator (BDFG), the grid connection strategy and maximum energy extraction control were both analyzed. Besides, the transient simulation of no-load model and generation model of the BDFG have been developed on the MATLAB/Simulink platform. The test results during cutting-in grid confirmed the good dynamic performance of grid synchronization and effective power control approach for the BDFG-based variable speed wind turbines.

关键词： brushless doubly-fed generator (BDFG) modeling grid connection control back-to-back pulse-width modulation (PWM) converter wind power generation

HTML PDF 收藏

Esophageal pulse oximetry is more accurate and detects hypoxemia earlier than conventional pulse oximetry

null

《医学前沿（英文）》 2012年第6卷第4期页码 406-410 doi: 10.1007/s11684-012-0217-3

摘要：

The esophagus is perfused directly by prominent arteries and may provide a more consistent tissue source for pulse oximetry. The goal of this study was to evaluate the sensitivity and accuracy of an esophageal pulse oximetry probe on patients during controlled hypoxemia in comparison to measurements obtained with conventional pulse oximetry (SpulseO₂). Forty-five ASA I–II adult patients were included in this prospective observational study. Nellcor digital oximetric probes were placed on finger tips for SpulseO₂ before anesthesia. After tracheal intubation, an esophageal probe was placed in the lower segment of the esophagus for esophageal oximetric monitoring (SoesO₂). All patients were disconnected from the breathing circuit to establish a controlled hypoxemia, and were re-connected to the breathing circuit and ventilated with 100% oxygen immediately when SoesO₂ dropped to 90%. Matched SoesO₂ and SpulseO₂ readings were recorded when SoesO₂measurements were at 100%, 95%, 90% and the lowest reading. The time for SoesO₂ and SpulseO₂ to drop from 100% to 95%, 90% and return to 100% was recorded. Oxygen saturation from arterial blood samples (SartO₂) was also measured at each time point respectively. The linear correlation coefficient of the regression analysis between SartO₂ and SoesO₂ was 0.954. The mean±2SD of the difference was 0.3%±4.3% for SoesO₂vs. SartO₂ and 6.8%±5.6% for SpulseO₂vs. SartO₂ (P<0.001). The 95% confidence interval for the absolute difference between SoesO₂ and SartO₂ was 0.3% to 0.7% and 6.2% to 7.4% between SpulseO₂ and SartO₂. The time to reach 90% saturation measured with SoesO₂ was approximately 94 seconds earlier than the SpulseO₂ (P<0.001). In conclusion, SoesO₂ is more accurate and enables earlier detection of hypoxemia when compared to conventional pulse oximetry during hypoxemia for patients undergoing general anesthesia.

关键词： esophageal pulse oximetry conventional pulse oximetry hypoxemia

HTML PDF 收藏

Power quality investigation of a solar PV transformer-less grid- connected system fed DVR

Akhil GUPTA,Saurabh CHANANA,Tilak THAKUR

《能源前沿（英文）》 2014年第8卷第2期页码 240-253 doi: 10.1007/s11708-014-0322-x

摘要： This paper presents a single stage transformer-less grid-connected solar photovoltaic (PV) system with an active and reactive power control. In the absence of active input power, the grid-tied voltage source converter (VSC) is operated in a reactive power generation mode, which powers the control circuitry, and maintains a regulated DC voltage to the VSC. A data-based maximum power point tracking (MPPT) control scheme which performs power quality control at a maximum power by reducing the total harmonic distortion (THD) in grid injected current as per IEEE-519/1547 standards is implemented. A proportional-integral (PI) controller based dynamic voltage restorer (DVR) control scheme is implemented which controls the grid side converter during single-phase to ground fault. The analysis includes the grid current THD along with the corresponding variation of the active and reactive power during the fault condition. The MPPT tracks the actual variable DC link voltage while deriving the maximum power from the solar PV array, and maintains the DC link voltage constant by changing the modulation index of the VSC. Simulation results using Matlab/Simulink are presented to demonstrate the feasibility and validations of the proposed novel MPPT and DVR control systems under different environmental conditions.

关键词： data-based maximum power point tracking (MPPT) total harmonic distortion (THD) proportional integral control voltage restorer pulse width modulation

HTML PDF 收藏

Edge preparation methods for cutting tools: a review

《机械工程前沿（英文）》 2023年第18卷第4期 doi: 10.1007/s11465-023-0766-y

摘要： Edge preparation can remove cutting edge defects, such as burrs, chippings, and grinding marks, generated in the grinding process and improve the cutting performance and service life of tools. Various edge preparation methods have been proposed for different tool matrix materials, geometries, and application requirements. This study presents a scientific and systematic review of the development of tool edge preparation technology and provides ideas for its future development. First, typical edge characterization methods, which associate the microgeometric characteristics of the cutting edge with cutting performance, are briefly introduced. Then, edge preparation methods for cutting tools, in which materials at the cutting edge area are removed to decrease defects and obtain a suitable microgeometry of the cutting edge for machining, are discussed. New edge preparation methods are explored on the basis of existing processing technologies, and the principles, advantages, and limitations of these methods are systematically summarized and analyzed. Edge preparation methods are classified into two categories: mechanical processing methods and nontraditional processing methods. These methods are compared from the aspects of edge consistency, surface quality, efficiency, processing difficulty, machining cost, and general availability. In this manner, a more intuitive understanding of the characteristics can be gained. Finally, the future development direction of tool edge preparation technology is prospected.

关键词： edge preparation method preparation principle cutting edge geometry edge characterization tool performance

HTML PDF 收藏

DFIG sliding mode control fed by back-to-back PWM converter with DC-link voltage control for variable speed wind turbine

Youcef BEKAKRA,Djilani BEN ATTOUS

《能源前沿（英文）》 2014年第8卷第3期页码 345-354 doi: 10.1007/s11708-014-0330-x

摘要： This paper proposes an indirect power control of doubly fed induction generator (DFIG) with the rotor connected to the electric grid through a back-to-back pulse width modulation (PWM) converter for variable speed wind power generation. Appropriate state space model of the DFIG is deduced. An original control strategy based on a variable structure control theory, also called sliding mode control, is applied to achieve the control of the active and reactive power exchanged between the stator of the DFIG and the grid. A proportional-integral-(PI) controller is used to keep the DC-link voltage constant for a back-to-back PWM converter. Simulations are conducted for validation of the digital controller operation using Matlab/Simulink software.

关键词： doubly fed induction generator (DFIG) wind turbine back-to-back pulse width modulation (PWM) DC-link voltage sliding mode control

HTML PDF 收藏

Structural design of morphing trailing edge actuated by SMA

Qi WANG, Zhiwei XU, Qian ZHU

《机械工程前沿（英文）》 2013年第8卷第3期页码 268-275 doi: 10.1007/s11465-013-0261-y

摘要：

In this paper, the morphing trailing edge is designed to achieve the up and down deflection under the aerodynamic load. After a detailed and accurate computational analysis to determine the SMA specifications and layout programs, a solid model is created in CATIA and the structures of the morphing wing trailing edge are produced by CNC machining. A set of DSP measurement and control system is designed to accomplish the controlling experiment of the morphing wing trailing edge. At last, via the force analysis, the trailing edge is fabricated with four sections of aluminum alloy, and the arrangement scheme of SMA wires is determined. Experiment of precise control integral has been performed to survey the control effect. The experiment consists of deflection angle tests of the third joint and the integral structure. Primarily, the ultimate deflection angle is tested in these two experiments. Therefore, the controlling experiment of different angles could be performed within this range. The results show that the deflection error is less than 4% and response time is less than 6.7 s, the precise controlling of the morphing trailing edge is preliminary realized.

关键词： morphing wing trailing edge shape memory alloy digital signal processor PID algorithm

HTML PDF 收藏

Frequencies of circular plate with concentric ring and elastic edge support

null

《机械工程前沿（英文）》 2014年第9卷第2期页码 168-176 doi: 10.1007/s11465-014-0299-5

摘要：

Exact solutions for the flexural vibrations of circular plates having elastic edge conditions along with rigid concentric ring support have been presented in this paper. Values of frequency parameter for the considered circular plate are computed for different sets of values of elastic rotational and translation restraints and the radius of internal rigid ring support. The results for the first three modes of plate vibrations are computed and are presented in tabular form. The effects of rotational and linear restraints and the radius of the rigid ring support on the vibration behavior of circular plates are studied over a wide range of non-dimensional parametric values. The values of the exact frequency parameter presented in this paper for varying values of restraint parameters and the radius of the rigid ring support can better serve in design and as benchmark solutions to validate the numerical methods obtained by using other methods of solution.

关键词： circular plate frequency elastic edge rigid ring mode switching

HTML PDF 收藏

Knife-edge technique for laser cooling

WANG Zhanshan, MA Shanshan, MA Yan, ZHAO Min, LIU Hengbiao

《机械工程前沿（英文）》 2007年第2卷第4期页码 468-473 doi: 10.1007/s11465-007-0081-z

摘要： The transfer characteristics of an atomic beam and the effect of laser were investigated in this paper. In the application of knife-edge technique, the temperature of atoms through laser cooling was measured. Results indicate that, after atoms are emitted from an atomic oven, the longer the atoms move, the worse the distribution of the atomic beam shows, regardless the laser cooling is taken or not. Laser cooling can reduce the transverse velocity of the atomic beam to several orders of magnitude and also increase the uniformity of an atomic beam. Knife-edge technique can measure the temperature of an atomic beam through laser cooling. The measurement accuracy depends on the pixel size of the charge coupled device (CCD), which is used for the fluorescent imaging of the atomic beam. The results are very important for the future experiments of laser cooling.

关键词： knife-edge technique uniformity coupled transfer fluorescent

HTML PDF 收藏

基于双正交复序列的高效扩频调制方法

史小红

《中国工程科学》 2012年第14卷第3期页码 108-112

摘要：

提出了一种采用双正交复序列的高效扩频调制与解调方法（DoCS）。输入数据比特流被分割为长度为M的组，每组的M比特作为输入码字，从2M-2个长度为L的DoCS序列中选择一条序列进行发送，被选中的序列以QPSK方式调制在载波上，实现扩频通信。文中还提出了一种前向相位校正(FPC)方法来解决该系统中收发两端的载波同步问题。

关键词：调制与解调技术高效扩频调制前向相位校正双正交码

HTML PDF 收藏

Real-time task processing method based on edge computing for spinning CPS

Shiyong YIN, Jinsong BAO, Jie LI, Jie ZHANG

《机械工程前沿（英文）》 2019年第14卷第3期页码 320-331 doi: 10.1007/s11465-019-0542-1

摘要： Spinning production is a typical continuous manufacturing process characterized by high speed and uncertain dynamics. Each manufacturing unit in spinning production produces various real-time tasks, which may affect production efficiency and yarn quality if not processed in time. This paper presents an edge computing-based method that is different from traditional centralized cloud computation because its decentralization characteristics meet the high-speed and high-response requirements of yarn production. Edge computing nodes, real-time tasks, and edge computing resources are defined. A system model is established, and a real-time task processing method is proposed for the edge computing scenario. Experimental results indicate that the proposed real-time task processing method based on edge computing can effectively solve the delay problem of real-time task processing in spinning cyber-physical systems, save bandwidth, and enhance the security of task transmission.

关键词： edge computing real-time task scheduling CPS spinning