scholarly journals Parameter Modeling Analysis and Experimental Verification on Magnetic Shielding Cylinder of All-Optical Atomic Spin Magnetometer

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Hong Zhang ◽  
Sheng Zou ◽  
Xi-Yuan Chen ◽  
Wei Quan

The ultrahigh sensitivity atomic spin magnetometer as the magnetic measurement sensor has received much concern. The performance of the magnetic shielding cylinder is one of the key factors constraining the atomic spin magnetometer’s sensitivity. In order to effectively improve the performances of the magnetic shielding, the parameter optimization models of the magnetic shielding cylinder were established in this paper. Under the condition of changing only one parameter while the others keeping constant, the effects of various parameters influencing the axial shielding coefficient were comprehensively analyzed, and the results showed that the smaller the innermost length, the innermost radius, and the radial spacing were, and the greater the axial spacing was, the better the shielding performance could be obtained. According to these results and the actual needs, the magnetic shielding cylinder was optimally designed, and then the shielding effects were simulated via the software Ansoft. The simulation results showed that the optimized magnetic shielding cylinder had the advantages of small size, high shielding performance, and lager uniformity than that of the nonoptimized one. The actual measurement results showed that the residual magnetism in the optimized magnetic shielding cylinder was below 0.1 nT, which was 2~4 times lower than the nonoptimized one.

Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1583
Author(s):  
Wei-Tse Kao ◽  
Jonq-Chin Hwang ◽  
Jia-En Liu

This study aimed to develop a three-phase permanent-magnet synchronous motor drive system with improvement in current harmonics. Considering the harmonic components in the induced electromotive force of a permanent-magnet synchronous motor, the offline response of the induced electromotive force (EMF) was measured for fast Fourier analysis, the main harmonic components were obtained, and the voltage required to reduce the current harmonic components in the corresponding direct (d-axis) and quadrature (q-axis) axes was calculated. In the closed-loop control of the direct axis and quadrature axis current in the rotor reference frame, the compensation amount of the induced EMF with harmonic components was added. Compared with the online adjustment of current harmonic injection, this simplifies the control strategy. The drive system used a 32-bit digital signal processor (DSP) TMS320F28069 as the control core, the control strategies were implemented in software, and a resolver with a resolver-to-digital converter (RDC) was used for the feedback of angular position and speed. The actual measurement results of the current harmonic improvement control show that the total harmonic distortion of the three-phase current was reduced from 5.30% to 2.31%, and the electromagnetic torque ripple was reduced from 15.28% to 5.98%. The actual measurement results verify the feasibility of this method.


1952 ◽  
Vol 87 (3) ◽  
pp. 541-542 ◽  
Author(s):  
H. E. Walchli ◽  
H. W. Morgan

1996 ◽  
Vol 116 (3) ◽  
pp. 348-353
Author(s):  
Saori Hosono ◽  
Susumu Torii ◽  
Daiki Ebihara

Electronics ◽  
2021 ◽  
Vol 10 (23) ◽  
pp. 2936
Author(s):  
Ming-An Chung ◽  
Cheng-Wei Hsiao ◽  
Chih-Wei Yang ◽  
Bing-Ruei Chuang

This paper proposes a small-slot antenna system (50 mm × 9 mm × 2.7 mm) for 4 × 4 multiple-input multiple-output (MIMO) on smart glasses devices. The antenna is set on the plastic temple, and the inverted F antenna radiates through the slot in the ground plane of the sputtered copper layer outside the temple. Two symmetrical antennas and slots on the same temple and series capacitive elements enhance the isolation between the two antenna ports. When both temples are equipped with the proposed antennas, 4 × 4 MIMO transmission can be achieved. The antenna substrate is made of polycarbonate (PC), and its thickness is 2.7 mm εr=2.85, tanδ=0.0092. According to the actual measurement results, this antenna has two working frequency bands when the reflection coefficient is lower than −10dB, its working frequency bandwidth at 4.58–5.72 GHz and 6.38–7.0 GHz. The proposed antenna has a peak gain of 4.3 dBi and antenna efficiency of 85.69% at 5.14 GHz. In addition, it also can obtain a peak gain of 3.3 dBi and antenna efficiency of 82.78% at 6.8 GHz. The measurement results show that this antenna has good performance, allowing future smart eyewear devices to be applied to Wi-Fi 5G (5.18–5.85 GHz) and Wi-Fi 6e (5.925–7.125 GHz).


2006 ◽  
Vol 16 (2) ◽  
pp. 1765-1768 ◽  
Author(s):  
H. Norikane ◽  
T. Nishikubo ◽  
S. Gokyu ◽  
K. Itoh ◽  
M. Itoh

2011 ◽  
Vol 135-136 ◽  
pp. 954-959
Author(s):  
Chang Bao Wen ◽  
Yong Feng Ju ◽  
Li Liu ◽  
Ya Fei Jiang ◽  
Chen Zhao ◽  
...  

In the design process of surface acoustic wave (SAW) device based on multistrip coupler (MSC), the characteristics of interdigital transducer (IDT) and device can not been directly achieved, and the layout structure of device can not be observed and checked. To solve some problems, the design platform of SAW device based MSC was realized in the Matlab design environment using the modular design. The design platform of SAW device based MSC consists of layout simulation module, characteristics simulation module and data output module. By means of realizing a SAW device based MSC with center frequency at 51.293MHz, the comparison and analysis between the design results and the actual test results are presented. Experiments results confirm that the platform can correctly design the device layout. The device characteristics achieved by the design platform are in good agreement with the actual measurement results by the network analyzer.


2014 ◽  
Vol 1048 ◽  
pp. 26-30 ◽  
Author(s):  
Xin Wang ◽  
Yuan Zhao ◽  
Hao Wang ◽  
Guang Ming Cai

Different spinnerets can be used to generate needleless electrospinning with the potential to scale up the production of nanofibers. However, the electrospinning performance, normally refers to the quality of the as-spun fiber and the production rate, is dramatically different from different spinnerets. This study focuses on the electric field of different spinnerets under the same experimental parameters so as to understand the key factors that affect the electrospinning performance of upward needleless electrospinning. Modeling analysis suggested that the electric field could be further concentrated by optimizing the geometry of spinneret. Experimental investigation on needleless electrospinning from different spinnerets proved that the electrospinning performance was improved greatly with the optimization of the electric field of spinneret. Understanding of the relationship between electric field and spinning performance would benefit the design and development of needleless electrospinning.


1994 ◽  
Vol 9 (6) ◽  
pp. 72-77
Author(s):  
M. Yamaguchi ◽  
S. Yabukami ◽  
K.I. Arai

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