scholarly journals A Novel Method Based on Oblique Projection Technology for Mixed Sources Estimation

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Weijian Si ◽  
Xiaolin Li ◽  
Yilin Jiang ◽  
Liangtian Wan
Keyword(s):  
Array Signal Processing ◽  
Near Field ◽  
Location Estimation ◽  
Noise Power ◽  
Oblique Projection ◽  
Computation Complexity ◽  
Range Estimation ◽  
Localization Algorithms ◽  
Partial Area ◽  
Novel Method

Reducing the computational complexity of the near-field sources and far-field sources localization algorithms has been considered as a serious problem in the field of array signal processing. A novel algorithm caring for mixed sources location estimation based on oblique projection is proposed in this paper. The sources are estimated at two different stages and the sensor noise power is estimated and eliminated from the covariance which improve the accuracy of the estimation of mixed sources. Using the idea of compress, the range information of near-field sources is obtained by searching the partial area instead of the whole Fresnel area which can reduce the processing time. Compared with the traditional algorithms, the proposed algorithm has the lower computation complexity and has the ability to solve the two closed-spaced sources with high resolution and accuracy. The duplication of range estimation is also avoided. Finally, simulation results are provided to demonstrate the performance of the proposed method.

Near Field EMC Scanning Method Based on an E-Field Collapse

2015 ◽  
Author(s):  
Jeff Dunnihoo ◽  
Pasi Tamminen ◽  
Toni Viheriäkoski
Keyword(s):  
Near Field ◽  
Electronic Systems ◽  
Inexpensive Method ◽  
Scanning Method ◽  
Field Information ◽  
Novel Method ◽  
Near Field Scanning

Abstract In this study we present a novel method to use a field collapse method together with fully automated near field scanning equipment to construct E- and H-field information of a system during transient ESD events. This inexpensive method provides an alternative way for system designers to validate and analyze the EMC/ESD capability of electronic systems without TLP pulsers, ESD simulators, or precision inductive current probes.

scholarly journals Hybrid multilevel plane wave based near-field far-field transformation utilising combined near- and far-field translations

2009 ◽  
Vol 7 ◽  
pp. 17-22 ◽  
Author(s):  
C. H. Schmidt ◽  
T. F. Eibert
Keyword(s):  
Near Field ◽  
Measurement Techniques ◽  
Plane Waves ◽  
Low Complexity ◽  
Far Field ◽  
Computation Complexity ◽  
Low Frequencies ◽  
Field Transformation ◽  
Translation Operators ◽  
Equivalent Sources

Abstract. The radiation of large antennas and those operating at low frequencies can be determined efficiently by near-field measurement techniques and a subsequent near-field far-field transformation. Various approaches and algorithms have been researched but for electrically large antennas and irregular measurement contours advanced algorithms with low computation complexity are required. In this paper an algorithm employing plane waves as equivalent sources and utilising efficient diagonal translation operators is presented. The efficiency is further enhanced using simple far-field translations in combination with the expensive near-field translations. In this way a low complexity near-field transformation is achieved, which works for arbitrary sample point distributions and incorporates a full probe correction without increasing the complexity.

scholarly journals Real-Time Monitoring of Jet Trajectory during Jetting Based on Near-Field Computer Vision

Sensors ◽  
2019 ◽  
Vol 19 (3) ◽  
pp. 690 ◽  
Author(s):  
Jinsong Zhu ◽  
Wei Li ◽  
Da Lin ◽  
Ge Zhao
Keyword(s):  
Computer Vision ◽  
Prediction Model ◽  
Real Time ◽  
Processing Time ◽  
Near Field ◽  
Image Correction ◽  
Noise Elimination ◽  
Sensor Device ◽  
Jet Trajectory ◽  
Novel Method

A novel method of near-field computer vision (NFCV) was developed to monitor the jet trajectory during the jetting process, which was used to precisely predict the falling point position of the jet trajectory. By means of a high-resolution webcam, the NFCV sensor device collected near-field images of the jet trajectory. Preprocessing of collected images was carried out, which included squint image correction, noise elimination, and jet trajectory extraction. The features of the jet trajectory in the processed image were extracted, including: start-point slope (SPS), end-point slope (EPS), and overall trajectory slope (OTS) based on the proposed mean position method. A multiple regression jet trajectory range prediction model was established based on these trajectory characteristics and the reliability of the model was verified. The results show that the accuracy of the prediction model is not less than 94% and the processing time is less than 0.88s, which satisfy the requirements of real-time online jet trajectory monitoring.

Biomimetic tough helicoidally structured material through novel electrospinning based additive manufacturing

MRS Advances ◽  
2019 ◽  
Vol 4 (43) ◽  
pp. 2345-2354 ◽  
Author(s):  
Komal Agarwal ◽  
Rahul Sahay ◽  
Avinash Baji ◽  
Arief S. Budiman
Keyword(s):  
Structural Design ◽  
Polyvinylidene Fluoride ◽  
Architectural Design ◽  
Mechanical Characteristics ◽  
Near Field ◽  
Structural Materials ◽  
Electrospinning Technique ◽  
Mantis Shrimp ◽  
Novel Method ◽  
Microstructural Design

ABSTRACTNatural structural materials (NSMs) such as nacre, teeth, bones and crustacean exoskeleton are usually made of weak biomaterials arranged in specific structural design imparting them remarkable mechanical characteristics. Such hierarchical structural layouts found in nature encourage designing of mechanically desirable synthetic structural materials (SSMs). Among variety of natural hierarchical layouts, this paper specifically focuses on helicoidal architectural design found in the tough dactyl club of mantis shrimp. We first decode the mechanics behind helicoidal microstructural design and document the development of impact resistant macroscale helicoidal architectured synthetic structural materials (HA-SSMs). Next, near-field electrospinning technique (NFES)- both melt (polycaprolactone) and solution (polyvinylidene fluoride) type has been discussed in detail, as a novel method for developing lab scale 3D biomimetic HA-SSMs in micro-nanoscale. Further, the effect of the helical arrangement, size of substructures and surface treatment on strength and toughness of NFES fabricated HA-SSMs samples is analysed.

scholarly journals Support Vector Regression for the Modeling and Synthesis of Near-Field Focused Antenna Arrays

Electronics ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 1352 ◽  
Author(s):  
Rafael González Ayestarán
Keyword(s):  
Support Vector Regression ◽  
Antenna Arrays ◽  
Near Field ◽  
Computational Cost ◽  
Support Vector ◽  
Analysis Tool ◽  
Training Samples ◽  
Learning Capabilities ◽  
Novel Method ◽  
The Individual

The powerful support vector regression framework is proposed in a novel method for near-field focusing using antenna arrays. By using this machine-learning method, the set of weights required in the elements of an array can be calculated to achieve an assigned near-field distribution focused on one or more positions. The computational cost is concentrated in an initial training process so that the trained system is fast enough for applications where moving devices are involved. The increased learning capabilities of support vector machines allow using a reduced number of training samples. Thus, these training samples may be generated with a prototype or a convenient electromagnetic analysis tool, and hence realistic effects, such as coupling or the individual radiation patterns of the elements of the arrays, are accounted for. Illustrative examples are presented.

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