Impact of Image Frequency Operation on Vector Mixer Characterization

2019 ◽  
Author(s):  
Konstantin Korotkov ◽  
Akim Babenko ◽  
Daniil Frolov ◽  
Dmitriy Nereutskiy ◽  
Anton Levchenko
Keyword(s):  
Image Frequency

scholarly journals Identification of blowing snow particles in images from a multi-angle snowflake camera

2018 ◽  
Author(s):  
Mathieu Schaer ◽  
Christophe Praz ◽  
Alexis Berne
Keyword(s):  
Austral Summer ◽  
Gaussian Mixture ◽  
Second Step ◽  
Blowing Snow ◽  
Kappa Score ◽  
Probabilistic Information ◽  
Complex Interactions ◽  
Field Campaigns ◽  
Number Of Particles ◽  
Image Frequency

Abstract. A new method to automatically discriminate between hydrometeors and blowing snow particles on Multi-Angle Snowflake Camera (MASC) images is introduced. The method uses four selected descriptors related to the image frequency, the number of particles detected per image as well as their size and geometry to classify each individual image. The classification task is achieved with a two components Gaussian Mixture Model fitted on a subset of representative images of each class from field campaigns in Antarctica and Davos, Switzerland. The performance is evaluated by labelling the subset of images on which the model was fitted. An overall accuracy and Cohen's Kappa score of 99.4 and 98.8 %, respectively, is achieved. In a second step, the probabilistic information is used to flag images composed of a mix of blowing snow particles and hydrometeors, which turns out to occur frequently. The percentage of images belonging to each class from an entire austral summer in Antartica and during a winter in Davos, respectively, are presented. The capability to distinguish precipitation, blowing snow and a mix of those in MASC images is highly relevant to disentangle the complex interactions between wind, snowflakes and snowpack close to the surface.

scholarly journals Frequency estimators with high resistance to interference from image frequency components

2018 ◽  
Vol 12 (2) ◽  
pp. 147-158 ◽  
Author(s):  
Wei Zhou ◽  
Liqun Gan ◽  
Hong Xiao ◽  
Yi Zhang ◽  
Haitao Xu ◽  
...  
Keyword(s):  
Mean Squared Error ◽  
Frequency Estimation ◽  
Geometric Mean ◽  
Random Noise ◽  
Estimation Algorithm ◽  
Side Lobe ◽  
Sine Wave ◽  
Practical Engineering ◽  
Frequency Components ◽  
Image Frequency

This paper presents an improved frequency estimation algorithm based on the interpolated discrete Fourier transform. High-accurate frequency estimation can be achieved by taking the geometric mean of two independent estimates, which are derived from the real parts of the two largest spectral bins and the imaginary parts, respectively. In situations where only a small number of sine wave cycles are observed, the ability of the algorithm to cancel interference from image frequency components results in improvements in accuracy. The residual errors of the proposed algorithm have been theoretically analyzed with maximum side-lobe decaying windows, since the windows have simple and uniform analytical expression of interpolation algorithm. The performance of the proposed algorithm was investigated using both Hanning and three-term maximum side-lobe decaying windows. A comparative analysis of systematic errors and noise sensitivity was performed between the new algorithm and traditional algorithms. Both the root mean squared error and the probability density of the errors were investigated under noisy conditions. Simulation results demonstrated that the new algorithm is not only highly resistant to interference from image components but is also resistant to the effects of random noise. The results presented in the paper are useful for identifying the best choice of algorithm in practical engineering applications.

scholarly journals CONTENT-BASED AUTOFOCUSING IN AUTOMATED MICROSCOPY

2010 ◽  
Vol 29 (3) ◽  
pp. 173 ◽  
Author(s):  
Peter Hamm ◽  
Janina Schulz ◽  
Karl-Hans Englmeier
Keyword(s):  
Phase Contrast ◽  
A Priori ◽  
A Priori Knowledge ◽  
Differential Interference Contrast ◽  
Field Phase ◽  
Bright Field ◽  
Automated Microscopy ◽  
Focus Plane ◽  
Object Features ◽  
Image Frequency

Autofocusing is the fundamental step when it comes to image acquisition and analysis with automated microscopy devices. Despite all efforts that have been put into developing a reliable autofocus system, recent methods still lack robustness towards different microscope modes and distracting artefacts. This paper presents a novel automated focusing approach that is generally applicable to different microscope modes (bright-field, phase contrast, Differential Interference Contrast (DIC) and fluorescence microscopy). The main innovation consists in a Content-based focus search that makes use of a priori knowledge about the observed objects by employing local object features and Boosted Learning. Hence, this method turns away from common autofocus approaches that apply solely whole image frequency measurements to obtain the focus plane. Thus, it is possible to exclude artefacts from being brought into focus calculation as well as locating the in-focus layer of specific microscopic objects.

Conversion Loss of Diode Mixers Having Image-Frequency Impedance

1945 ◽  
Vol 33 (9) ◽  
pp. 603-609 ◽  
Author(s):  
E.W. Herold ◽  
R.R. Bush ◽  
W.R. Ferris
Keyword(s):  
Conversion Loss ◽  
Image Frequency

siFLIM: single-image frequency-domain FLIM provides fast and photon-efficient lifetime data

2016 ◽  
Vol 13 (6) ◽  
pp. 501-504 ◽  
Author(s):  
Marcel Raspe ◽  
Katarzyna M Kedziora ◽  
Bram van den Broek ◽  
Qiaole Zhao ◽  
Sander de Jong ◽  
...  
Keyword(s):  
Frequency Domain ◽  
Lifetime Data ◽  
Single Image ◽  
Image Frequency

scholarly journals Low insertion loss of surface mount device low pass filter at 700 MHz

2019 ◽  
Vol 8 (2) ◽  
pp. 382-388
Author(s):  
Khairil Anuar Khairi ◽  
Mohd Faizal Jamlos ◽  
Surentiran Padmanathan ◽  
Mohd Aminudin Jamlos ◽  
Muammar Mohamad Isa
Keyword(s):  
Transition Region ◽  
Insertion Loss ◽  
Power Supply ◽  
Cutoff Frequency ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Surface Mount ◽  
Low Pass ◽  
Low Insertion Loss ◽  
Image Frequency

The paper involved with the design, simulation and fabrication of 6th order elliptical-based Surface Mount Device (SMD) LPF with cutoff frequency at 700 MHz. Fabricated LPF is consisted of four PCB layers which components of SMD are soldered on the top layer. Another three layers is for grounding and shielding, power supply and grounding void. The four layers is crucial to avoid interference between components. The research has find out that the momentum simulation is definitely required to improve the signals response compared to a normal simulation by ADS software. The comparison between momentum simulated versus measured and normal simulated versus measured is 0.2 dB and 29 dB correspondingly. Such huge difference leads to conclusion that momentum simulation is saving time without having much struggles and efforts to get optimum readings. The Proposed SMD LPF has a very low insertion loss of 0.965dB with a transition region of 195 MHz which is good steepness to avoid any image frequency.

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