The Research of Non-Uniformity Correction of Infrared Image in Thermal Wave Testing Based on Homomorphism Technology

2011 ◽  
Vol 58-60 ◽  
pp. 2376-2380
Author(s):  
Yuan Jia Song ◽  
Wei Zhang ◽  
Zheng Wei Yang ◽  
Guo Feng Jin
Keyword(s):  
Thermal Wave ◽  
Signal To Noise Ratio ◽  
Infrared Image ◽  
Future Research ◽  
Infrared Images ◽  
Signal To Noise ◽  
Improve Image Quality ◽  
High Noise ◽  
Low Contrast ◽  
Homomorphic Filtering

The infrared thermal wave technology is a new nondestructive testing (NDT) method with a kind of advantage, including non-contact, intuitionistic, fast et al. But the infrared images always have defects that the low-contrast and high-noise due to uneven brightness and calefaction in the testing process, which enhance the difficulty of following quantitative distinguishment of defects. Therefore, the improved homomorphic filtering is given in this article. The detailed processes of the method and testing results are given. The results of the experiments show that the method has higher peak signal to noise ratio (PSNR), can improve image quality, which establish basis for future research of image segmentation.

Hippocampus Segmentation Techniques: A Survey

2013 ◽  
Vol 760-762 ◽  
pp. 2086-2090 ◽  
Author(s):  
Bing Song He ◽  
Xue Ping Zhang ◽  
Yong Gang Shi
Keyword(s):  
Human Brain ◽  
Clinical Diagnosis ◽  
Hippocampal Formation ◽  
Signal To Noise Ratio ◽  
Future Research ◽  
Mr Images ◽  
Signal To Noise ◽  
Low Contrast ◽  
Early Biomarker ◽  
Hippocampus Segmentation

Since the volume of hippocampal formation has been found to be an early biomarker for MCI and Alzheimer's disease, hippocampus segmentation plays a significant role in clinical diagnosis. Because hippocampus in MR images presents features of low contrast, low signal-to-noise ratio and discontinuous boundaries, accurate segmentation still remains a challenging task. We presented a survey of the methods used to segment the hippocampal formation in MR images of human brain and concluded with a discussion on the trend of the future research in hippocampus segmentation.

3 T: the good, the bad and the ugly

2021 ◽  
Author(s):  
Martin John Graves
Keyword(s):  
Signal To Noise Ratio ◽  
Relaxation Times ◽  
Blood Oxygen Level Dependent ◽  
Blood Oxygen ◽  
Rf Power ◽  
Blood Oxygen Level ◽  
Signal To Noise ◽  
Improve Image Quality ◽  
Mr Physics ◽  
T System

It is around 20 years since the first commercial 3 T MRI systems became available. The theoretical promise of twice the signal-to-noise ratio of a 1.5 T system together with a greater sensitivity to magnetic susceptibility-related contrast mechanisms, such as the blood oxygen level dependent (BOLD) effect that is the basis for functional MRI (fMRI), drove the initial market in neuroradiology. However, the limitations of the increased field strength soon became apparent, including the increased radiofrequency (RF) power deposition, tissue dependent changes in relaxation times, increased artifacts, and greater safety concerns. Many of these issues are dependent upon MR physics and work arounds have had to be developed to try and mitigate their effects. This article reviews the underlying principles of the good, the bad and the ugly aspects of 3 T, discusses some of the methods used to improve image quality and explains the remaining challenges and concerns.

Throughput Dependence on SNR in IEEE802.11 WLAN Systems

2019 ◽  
pp. 1307-1323
Author(s):  
Ikponmwosa Oghogho
Keyword(s):  
High Throughput ◽  
Signal To Noise Ratio ◽  
Physical Layer ◽  
Future Research ◽  
Cross Layer ◽  
Signal To Noise ◽  
Research Directions ◽  
Data Rates ◽  
Research Findings ◽  
Future Research Directions

This chapter seeks to present the dependence of throughput on signal to noise ratio (SNR) in IEEE802.11 WLAN systems. High throughput and low delays are presented as the requirements for indicating good performance of WLAN systems. The multiple communication data rates specified by the physical layer of IEEE802.11 WLANs which vary depending on the SNR observed is shown to appreciably influence the throughput experienced by the users. Cross-layer modelling principles which simplifies the process of estimating the dependence of throughput on SNR is presented. Recent research findings which apply cross-layer modelling principles to model the dependence of throughput on SNR only is presented along with future research directions.

scholarly journals Few-View Prereconstruction Guided Tube Current Modulation Strategy Based on the Signal-to-Noise Ratio of the Sinogram

2015 ◽  
Vol 2015 ◽  
pp. 1-8
Author(s):  
Ming Chang ◽  
Yongshun Xiao ◽  
Zhiqiang Chen
Keyword(s):  
Radiation Dose ◽  
Signal To Noise Ratio ◽  
Main Idea ◽  
Tube Current Modulation ◽  
Exposure Control ◽  
Signal To Noise ◽  
Current Modulation ◽  
Low Contrast ◽  
Tube Current ◽  
View Reconstruction

The radiation dose reduction without sacrificing the image quality as an important issue has raised the attention of CT manufacturers and different automatic exposure control (AEC) strategies have been adopted in their products. In this paper, we focus on the strategy of tube current modulation. It is deduced based on the signal-to-noise (SNR) of the sinogram. The main idea behind the proposed modulation strategy is to keep the SNR of the sinogram proximately invariable using the few-view reconstruction as a good reference because it directly affects the noise level of the reconstructions. The numerical experiment results demonstrate that, compared with constant tube current, the noise distribution is more uniform and the SNR and CNR of the reconstruction are better when the proposed strategy is applied. Furthermore it has the potential to distinguish the low-contrast target and to reduce the radiation dose.

scholarly journals Key Points’ Location in Infrared Images of the Human Body Based on Mscf-ResNet

2021 ◽  
Vol 14 (1) ◽  
pp. 15
Author(s):  
Shengguo Ge ◽  
Siti Nurulain Mohd Rum
Keyword(s):  
Human Body ◽  
Infrared Image ◽  
Research Direction ◽  
Brightness Distribution ◽  
Future Research ◽  
Infrared Images ◽  
Positioning Accuracy ◽  
Main Research ◽  
Multi Scale ◽  
Key Points

The human body generates infrared radiation through the thermal movement of molecules. Based on this phenomenon, infrared images of the human body are often used for monitoring and tracking. Among them, key point location on infrared images of the human body is an important technology in medical infrared image processing. However, the fuzzy edges, poor detail resolution, and uneven brightness distribution of the infrared image of the human body cause great difficulties in positioning. Therefore, how to improve the positioning accuracy of key points in human infrared images has become the main research direction. In this study, a multi-scale convolution fusion deep residual network (Mscf-ResNet) model is proposed for human body infrared image positioning. This model is based on the traditional ResNet, changing the single-scale convolution to multi-scale and fusing the information of different receptive fields, so that the extracted features are more abundant and the degradation problem, caused by the excessively deep network, is avoided. The experiments show that our proposed method has higher key point positioning accuracy than other methods. At the same time, because the network structure of this paper is too deep, there are too many parameters and a large volume of calculations. Therefore, a more lightweight network model is the direction of future research.

scholarly journals Optimization of Direct Direction Finding Method with Two-Dimensional Correlative Processing of Spatial Signal

2018 ◽  
Vol 8 ◽  
pp. 46-53
Author(s):  
Vitaliy V. Tsyporenko ◽  
Valentyn G. Tsyporenko
Keyword(s):  
Main Parameter ◽  
Noise Immunity ◽  
Signal To Noise Ratio ◽  
Direction Finding ◽  
High Accuracy ◽  
Signal To Noise ◽  
High Noise ◽  
Spatial Shift ◽  
Simulation Results ◽  
Finding Method

In this article, the main parameter of the correlative-interferometric direction finding method with twodimensional correlative processing of spatial signal in the aperture of a linear antenna array (AA) is determined as the value of spatial shift within the AA aperture. The corresponding objective function is also formed. Analytical optimization of this parameter is presented and a comparative analysis of analytical calculations based on simulation results is conducted. In the simulation, a range of dependencies of the middle square deviation of estimation of direction on the value of the spatial shift for a signal-to-noise ratio of 0 dB, for minimum 3-sample and 4-sample Blackman-Harris windows of the spectral analysis, is received. The value of the middle square deviation of estimation of direction will be minimal and will equal 0.02 degrees using a minimum 3-sample Blackman-Harris window with the −67 dB level of side lobes. It offers high noise immunity and high accuracy of direction finding.

On Ambient Information Systems

2010 ◽  
pp. 145-155
Author(s):  
William R. Hazlewood ◽  
Lorcan Coyle
Keyword(s):  
Information Systems ◽  
Web 2.0 ◽  
Physical Environment ◽  
Information Overload ◽  
Signal To Noise Ratio ◽  
Physical World ◽  
Research Community ◽  
Future Research ◽  
The Internet ◽  
Signal To Noise

The rise of the Internet, the ever increasing ubiquity of data, and its low signal-to-noise ratio have contributed to the problem of information overload, whereby individuals have access to more data than they can assimilate into meaningful and actionable information. Much of the success of Web 2.0 has been achieved after an effective tackling of this problem. Ambient Information Systems take the battle into the physical world by integrating information into the physical environment in a non-intimidating and non-overloading fashion. After two international workshops on Ambient Information Systems, we outline our vision for the field, consolidate a new definition, identify the key concerns of the research community, and issue a call to arms for future research.

Research on Enhanced of Mine-Underground Picture

2012 ◽  
Vol 490-495 ◽  
pp. 548-552
Author(s):  
Meng Ling Zhao ◽  
Min Xia Jiang
Keyword(s):  
Image Quality ◽  
Signal To Noise Ratio ◽  
Ccd Camera ◽  
Histogram Equalization ◽  
Uniform Illumination ◽  
Improve Image Quality ◽  
Low Contrast ◽  
Enhancement Method ◽  
Field Information ◽  
Time Image

Because of the based on S3C6410 Field information recorder mine- underground non-uniform illumination and mine- underground non-uniform illumination that a large of noise collected and transferred,image is low contrast ,dim and dark. Based on the theory of Donoho's wavelet threshold denoising, several typical wavelet threshold denoising methods are compared.the best denoising effect of peak signal to noise ratio is obtained. The image enhancement method that combination of the adaptive thresholding denoising and histogram equalization is proposed. The experiment result shows that the method has a good denoising performance, which removed the readout noise of CCD Camera,at the same time, image quality is improved .So the wavelet enhancement in image processing of mine- underground can improve image quality.

scholarly journals Estimation technique of global fringe visibility using in interferometers with adjustable visibility

2020 ◽  
Author(s):  
fu-zhong bai ◽  
Jiayi Chen ◽  
Xiaojuan Gao ◽  
Yongxiang Xu
Keyword(s):  
Theoretical Model ◽  
Fringe Pattern ◽  
Signal To Noise Ratio ◽  
Estimation Technique ◽  
Signal To Noise ◽  
Fringe Visibility ◽  
Low Contrast ◽  
Accuracy Measurement ◽  
Noise Ratio

Abstract In the accuracy measurement of phase from interferometers with adjustable fringe visibility, it needs to estimate the visibility of experimental patterns so as to obtain the interference patterns with the maximum visibility. We develop the Fourier-polar transform and combine the directional projection to estimate the global visibility of carrier fringe pattern. The technique is especially used for low-quality fringe pattern such as low contrast and low (signal to noise ratio) SNR that often appear in the interferometric experiment. An illustrative experiment based on the radial shearing interferometer is given. Results generated from this technique are compared with the derived values from theoretical model, and exemplary agreement between both is demonstrated.

scholarly journals The effect of tonsillectomy on voice quality

2020 ◽  
Vol 148 (9-10) ◽  
pp. 560-564
Author(s):  
Sanja Djokovic ◽  
Vladan Plecevic ◽  
Tamara Kovacevic ◽  
Sinisa Solaja ◽  
Bojana Vukovic
Keyword(s):  
Standard Deviation ◽  
Signal To Noise Ratio ◽  
Pediatric Population ◽  
Voice Quality ◽  
Future Research ◽  
Signal To Noise ◽  
Adenoid Tissue ◽  
Patient Voice ◽  
Noise Ratio ◽  
The Voice

Introduction/Objective. Tonsillitis is a very common condition found in the pediatric population but also in adult patients. One of the consequences of such conditions is poor voice quality. Hoarseness, poor voice impostation, interruption, and hypernazalization are just some of the differences in patient voice quality. The objective of this paper was to examine the effects of tonsillectomy on the voice quality. Methods. The sample included 37 patients, 17 female and 20 male, ranging in age 3?39 years. The method involved recording patients one month before and one month after tonsillectomy with a digital sound recorder, with recordings analyzed in the Praat program. The variables monitored in the basic voice were as follows: voice pitch, standard deviation of voice, degree of voice interruption, jitter, shimmer, and signal-to-noise ratio. In the statistical analysis, in addition to standard descriptive analyzes, t-test and ACNOVA were also used. Results. The results showed that there are effects of tonsillectomy on standard deviation of baseline voice (p = 0.002), shimmer (p = 0.002), baseline voice interruption rate (p = 0.023), signal to noise ratio (p = 0.003). There were no differences in the effects of tonsillectomy with respect to the sex of the subjects. Conclusion. Based on the conducted research, there were some methodological conclusions that could be considered as a recommendation for future research: increase the number of persons in the sample, introduce a variable of chronological age, type of surgical intervention, and gradation of size of the tonsil and adenoid tissue.

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