Investigation of Temperature Fluctuation of Diode-Rectified Multiphase AC Arc by High-Speed Visualization

An innovative multiphase AC arc was drastically improved by diode-rectification technique with bipolar electrode. Temperature fields and arc behaviour of the diode-rectified multiphase AC was successfully visualized on the basis of the high-speed camera technique with appropriate band-pass filter optics. Arc temperature was measured by Boltzmann plot method with two line emissions from atomic argon at 675.2834 nm and 794.8176 nm. Arc temperature fluctuates in the range from 7,000 to 13,000 K. The arc temperature near the cathode was higher than 13,000 K, while that near the anode was about 10,000 K. Arc temperature in the centre region in the furnace was about 7,000–9,000 K, which is sufficiently high to melt and evaporate the refractory metals or ceramics. Obtained results suggested the diode-rectified multiphase AC arc is a promising thermal plasma source for material processing at high productivity.

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Preparation of Nickel Nanoparticles by Direct Current Arc Discharge Method and Their Catalytic Application in Hybrid Na-Air Battery

Nanomaterials ◽

10.3390/nano8090684 ◽

2018 ◽

Vol 8 (9) ◽

pp. 684 ◽

Cited By ~ 9

Author(s):

Fengmei Su ◽

Xuechao Qiu ◽

Feng Liang ◽

Manabu Tanaka ◽

Tao Qu ◽

...

Keyword(s):

Direct Current ◽

Composite Structures ◽

High Speed ◽

Large Scale ◽

Nickel Nanoparticles ◽

Arc Discharge ◽

Band Pass Filter ◽

Pass Filter ◽

Air Battery ◽

Discharge Method

Nickel nanoparticles were prepared by the arc discharge method. Argon and argon/hydrogen mixtures were used as plasma gas; the evaporation of anode material chiefly resulted in the formation of different arc-anode attachments at different hydrogen concentrations. The concentration of hydrogen was fixed at 0, 30, and 50 vol% in argon arc, corresponding to diffuse, multiple, and constricted arc-anode attachments, respectively, which were observed by using a high-speed camera. The images of the cathode and anode jets were observed with a suitable band-pass filter. The relationship between the area change of the cathode/anode jet and the synchronous voltage/current waveform was studied. By investigating diverse arc-anode attachments, the effect of hydrogen concentration on the features of nickel nanoparticles were investigated, finding that 50 vol% H2 concentration has high productivity, fine crystallinity, and appropriate size distribution. The synthesized nickel nanoparticles were then used as catalysts in a hybrid sodium–air battery. Compared with commercial a silver nanoparticle catalyst and carbon black, nickel nanoparticles have better electrocatalytic performance. The promising electrocatalytic activity of nickel nanoparticles can be ascribed to their good crystallinity, effective activation sites, and Ni/NiO composite structures. Nickel nanoparticles prepared by the direct current (DC) arc discharge method have the potential to be applied as catalysts on a large scale.

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The Transceiver Circuit Design of Digital Ultrasonic System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.834-836.968 ◽

2013 ◽

Vol 834-836 ◽

pp. 968-973

Author(s):

Xiao Feng Zhang ◽

Fo Chang Xie ◽

Guo Wei Yang ◽

Wei Zhang

Keyword(s):

Circuit Design ◽

High Voltage ◽

High Speed ◽

Power Input ◽

High Gain ◽

Low Noise ◽

Band Pass Filter ◽

Echo Signal ◽

Pass Filter ◽

Input Use

This paper introduces the design process of the digital ultrasonic transmission circuit: echo receiving circuit and the echo signal regulate circuit. Among them, outside 500 V DC - DC module for high voltage power input, use non-tuned type circuit design ultrasonic transmission circuit ; Select high voltage fast recovery diode FR107 design echo receiving limiter circuit; Using ultra-high speed, low noise, low distortion of the integrated operational amplifier MAX4104ESA design preamplifier circuits and the band-pass filter circuits; Using linear decibels, low noise, wide bandwidth, high gain accuracy amplifier AD603 design echo amplifying circuit. The experimental results indicate that the basic realization of the ultrasonic transceiver circuit and echo signal conditioning functions.

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Development of Innovative Fringe Locking Strategies for Vibration-Resistant White Light Vertical Scanning Interferometry (VSI)

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.437.89 ◽

2010 ◽

Vol 437 ◽

pp. 89-94 ◽

Cited By ~ 2

Author(s):

Liang Chia Chen ◽

Abraham Mario Tapilouw ◽

Sheng Lih Yeh ◽

Shyh Tsong Lin ◽

Jin Liang Chen ◽

...

Keyword(s):

White Light ◽

High Speed ◽

Experimental Result ◽

Band Pass Filter ◽

Pass Filter ◽

Nano Scale ◽

Image Sensing ◽

Vertical Range ◽

Environmental Vibration ◽

Vertical Scanning Interferometry

White light interferometry has become an important method for measuring micro surface profiles with a long vertical range and nano-scale resolution. However, environmental vibration encountered in in-field optical inspection is usually unavoidable and it affects measurement performance significantly. Isolating vibration sources from the measurement system sometimes is not completely effective, especially within complicated in-field fabrication environment. Therefore, in this research we aim to develop a novel method in achieving white-light fringe-locking condition during vertical scanning processes. The developed optical system consists of white light source, a Mirau objective, a PZT vertical scanner, an optical band-pass filter and two image sensing devices. The developed system generates a high and a low coherent interferograms, simultaneously captured by two charged coupled devices (CCDs). The high coherent interferogram is employed to detect high-speed nano-scale displacement and direction of the external vibration. An innovative real time fringe-locking operation is performed and a new vertical scanning technique is performed accordingly to isolate vertical scanning from environmental disturbances. The feasibility of the anti-vibration VSI system is verified by performing some of industrial in-field examples. Based on the experimental result, the fringe locking technique can improve the measurement result.

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Active Damping Stabilization for High-Speed BLDCM Drive System Based on Band-Pass Filter

IEEE Transactions on Power Electronics ◽

10.1109/tpel.2016.2608928 ◽

2017 ◽

Vol 32 (7) ◽

pp. 5438-5449 ◽

Cited By ~ 9

Author(s):

Xinda Song ◽

Shiqiang Zheng ◽

Bangcheng Han ◽

Cong Peng ◽

Xinxiu Zhou

Keyword(s):

High Speed ◽

Active Damping ◽

Drive System ◽

Band Pass Filter ◽

Pass Filter ◽

Band Pass

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Design and Implementation of a Long Range Indoor VLC System using PWM

Annals of Emerging Technologies in Computing ◽

10.33166/aetic.2019.01.003 ◽

2019 ◽

Vol 3 (1) ◽

pp. 20-27 ◽

Cited By ~ 1

Author(s):

Majed Basha ◽

Martin J. Sibley ◽

Peter J. Mather

Keyword(s):

High Speed ◽

Pulse Width Modulation ◽

Low Cost ◽

Transmission Range ◽

Band Pass Filter ◽

Ambient Light ◽

Visible Light Communications ◽

Pass Filter ◽

Light Interference ◽

Front End

Visible Light Communications (VLC) is currently considered one of the most promising Optical Wireless Communications (OWC) for commercial applications, due to the widespread deployment of Light Emitting Diodes (LEDs) for energy efficiency, durability and low cost. With the ability to provide several THz of bandwidth, VLC is expected to co-exist with legacy and future Radio Frequency (RF) media as a reliable solution to the rapid demand of high-speed wireless communication. VLC is challenged by two main drawbacks: ambient light interference and the transmission range. To overcome these drawbacks, we propose a tuned VLC Analog Front-End (AFE) using simple and low-cost electronic circuity. The proposed VLC receiver architecture consists of a transimpedance amplifier, a fourth order Multiple Feed Back (MFB) band pass filter and a comparator. Experimental results demonstrated that by employing the proposed front-end the VLC transmission range could be extended up to 4.7 m by using Pulse Width Modulation (PWM). Moreover, the proposed system showed robustness against ambient light interference under the indoor scenario.

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One Abstraction Method for Displacement Response in the Sweep-Frequency Testing of Rotating Spindle

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.693.1377 ◽

2016 ◽

Vol 693 ◽

pp. 1377-1384

Author(s):

Yu Zhu Guo ◽

Tian Ning Chen ◽

Xiao Peng Wang ◽

Yan Fei Xu

Keyword(s):

Frequency Domain ◽

High Speed ◽

Measured Signal ◽

Band Pass Filter ◽

Shape Error ◽

Cnc Milling ◽

Sweep Frequency ◽

Pass Filter ◽

Time Frequency ◽

Displacement Response

ion Method for Displacement Response in the Sweep-Frequency Testing of Rotating Spindle Guo Yuzhu1,a*, Chen Tianning1,b, Wang Xiaopeng1,c and Xu Yanfei11 State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi’an Jiaotong University, 710049 Xi’an, China [email protected], [email protected], [email protected] Keywords: Rotating spindle; Sweep-frequency measurement; Error separation. Abstract. In the measurement of motorized spindle dynamic performance, the non-contact sweep-frequency excitation is adopted to obtain the displacement response of spindle rotor under high speed rotating. Due to the shape error at measurement section, eccentric error and random vibration, the illusory signals is introduced to the practical measured signal, which makes it difficult to analyze the displacement response. To effectively separate the error, a new method combining template signal and slip filtering is presented. After analyzing the characteristics of displacement response and illusory signals in time-frequency domain, the template signal constructed by the non-superposing portions between response and error is employed to eliminate the error in superposing portions. And a band-pass filter which can slip in time-frequency domain is employed to eliminate the other error. A spindle of CNC milling machine is tested at 7000 r/min, and the analysis result shows that the displacement response can be abstracted successfully from the original signal measured by rotating spindle.

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Improve Temporal Fourier Transform Profilometry for Complex Dynamic Three-Dimensional Shape Measurement

Sensors ◽

10.3390/s20071808 ◽

2020 ◽

Vol 20 (7) ◽

pp. 1808

Author(s):

Yihang Liu ◽

Qican Zhang ◽

Haihua Zhang ◽

Zhoujie Wu ◽

Wenjing Chen

Keyword(s):

Fourier Transform ◽

High Speed ◽

Three Dimensional ◽

Reference Plane ◽

Shape Measurement ◽

Band Pass Filter ◽

Pass Filter ◽

Fourier Transform Profilometry ◽

Sharp Edges ◽

Band Pass

The high-speed three-dimensional (3-D) shape measurement technique has become more and more popular recently, because of the strong demand for dynamic scene measurement. The single-shot nature of Fourier Transform Profilometry (FTP) makes it highly suitable for the 3-D shape measurement of dynamic scenes. However, due to the band-pass filter, FTP method has limitations for measuring objects with sharp edges, abrupt change or non-uniform reflectivity. In this paper, an improved Temporal Fourier Transform Profilometry (TFTP) algorithm combined with the 3-D phase unwrapping algorithm based on a reference plane is presented, and the measurement of one deformed fringe pattern producing a new 3-D shape of an isolated abrupt objects has been achieved. Improved TFTP method avoids band-pass filter in spatial domain and unwraps 3-D phase distribution along the temporal axis based on the reference plane. The high-frequency information of the measured object can be well preserved, and each pixel is processed separately. Experiments verify that our method can be well applied to a dynamic 3-D shape measurement with isolated, sharp edges or abrupt change. A high-speed and low-cost structured light pattern sequence projection has also been presented, it is capable of projection frequencies in the kHz level. Using the proposed 3-D shape measurement algorithm with the self-made mechanical projector, we demonstrated dynamic 3-D reconstruction with a rate of 297 Hz, which is mainly limited by the speed of the camera.

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Real-Time Traffic Light Detection with Frequency Patterns Using a High-Speed Camera

Sensors ◽

10.3390/s20144035 ◽

2020 ◽

Vol 20 (14) ◽

pp. 4035 ◽

Cited By ~ 1

Author(s):

Kento Yabuuchi ◽

Masahiro Hirano ◽

Taku Senoo ◽

Norimasa Kishi ◽

Masatoshi Ishikawa

Keyword(s):

Real Time ◽

High Speed ◽

Detection System ◽

Band Pass Filter ◽

High Speed Camera ◽

Traffic Light ◽

Pass Filter ◽

Real Time Processing ◽

Traffic Lights ◽

Original Dataset

LEDs are widely employed as traffic lights. Because most LED traffic lights are driven by alternative power, they blink at high frequencies, even at twice their frequencies. We propose a method to detect a traffic light from images captured by a high-speed camera that can recognize a blinking traffic light. This technique is robust under various illuminations because it can detect traffic lights by extracting information from the blinking pixels at a specific frequency. The method is composed of six modules, which includes a band-pass filter and a Kalman filter. All the modules run simultaneously to achieve real-time processing and can run at 500 fps for images with a resolution of 800 × 600. This technique was verified on an original dataset captured by a high-speed camera under different illumination conditions such as a sunset or night scene. The recall and accuracy justify the generalization of the proposed detection system. In particular, it can detect traffic lights with a different appearance without tuning parameters and without datasets having to be learned.

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