Automatic Determination of the Gaussian Noise Level on Digital Images by High-Pass Filtering for Regions of Interest

2018 ◽  
Vol 54 (4) ◽  
pp. 662-670 ◽  
Author(s):  
S. V. Balovsyak ◽  
Kh. S. Odaiska
2013 ◽  
Vol 717 ◽  
pp. 529-532
Author(s):  
Gwang Gil Jeon

In this paper, we propose a simple noise assessment approach for sensors. We assume the input signal is contaminated by white additive and zero mean Gaussian noise which. To measure the noise level, we the intensity-homogeneous blocks are found first, and then we evaluate the noise variance in the blocks. To determined intensity-homogeneous blocks, we use high pass filter. Experimental results show that the presented method provides good performance for natural and artificial images over a large range of noise levels.


1984 ◽  
Vol 23 (06) ◽  
pp. 277-282 ◽  
Author(s):  
A. Van Lingen ◽  
G. Westera ◽  
M. van ◽  
W. Den Hollander ◽  
E. E. Van der Wall ◽  
...  

SummaryThis paper presents an alternative method of demarcating regions of in terest over the myocardium after ad ministration of 123I-heptadecanoic acid to patients with coronary artery disea se. In a matrix of 32 × 32 pixels the elimination rates of the radioactivity, which are not corrected for back ground activity, are visualized per pixel in a functional image. The func tional image showed areas in the myocardium with high values of uncorrected elimination rates. These areas corresponded with the tracer defects on the scintigram. Corrected elimination rates obtained from re gions of interest of functional images were comparable with those of scinti grams. Thus based on functional im ages of uncorrected elimination rates a reliable, objective determination of regions of interest over normal and abnormal myocardium can be made.


2000 ◽  
Vol 28 (1-2) ◽  
pp. 237-245 ◽  
Author(s):  
Nasser Hosseini ◽  
Blanka Hejdukova ◽  
Pall E. Ingvarsson ◽  
Bo Johnels ◽  
Torsten Olsson

Author(s):  
Romain Desplats ◽  
Timothee Dargnies ◽  
Jean-Christophe Courrege ◽  
Philippe Perdu ◽  
Jean-Louis Noullet

Abstract Focused Ion Beam (FIB) tools are widely used for Integrated Circuit (IC) debug and repair. With the increasing density of recent semiconductor devices, FIB operations are increasingly challenged, requiring access through 4 or more metal layers to reach a metal line of interest. In some cases, accessibility from the front side, through these metal layers, is so limited that backside FIB operations appear to be the most appropriate approach. The questions to be resolved before starting frontside or backside FIB operations on a device are: 1. Is it do-able, are the metal lines accessible? 2. What is the optimal positioning (e.g. accessing a metal 2 line is much faster and easier than digging down to a metal 6 line)? (for the backside) 3. What risk, time and cost are involved in FIB operations? In this paper, we will present a new approach, which allows the FIB user or designer to calculate the optimal FIB operation for debug and IC repair. It automatically selects the fastest and easiest milling and deposition FIB operations.


2018 ◽  
Vol 69 (4) ◽  
pp. 875-880
Author(s):  
Oana Roxana Chivu ◽  
Ovidiu Mederle ◽  
Augustin Semenescu ◽  
Ileana Mates ◽  
Claudiu Babis ◽  
...  

The paper describes how to determine the noise in a production hall where there are production machines and equipment. The chosen plant is a production unit where filling of the polyurethane foam tubes is performed. The main activity is the production of professional insulators and wholesale of other products from the same range enumerating the following: wholesale chemical products; production of professional insulators; trade in chemicals and chemical industry. The recommended maximum admissible value for a normal 8h work program is 85 dB (A). The objective is to determine the level of noise in the factory and how it acts as a physical professional risk factor and its effects on the human body. The way in which the proposed objective was achieved was to determine the value of the noise level with the specialized equipment. Following the determinations that will be presented in the following chapters, appropriate protective measures have been taken.


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