Wyniki wyszukiwania - BazTech

1

Denoising methods for improving automatic segmentation in OCT images of human eye

Stankiewicz A., Marciniak T., Dąbrowski A., Stopa M., Rakowicz P., Marciniak E.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2017

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Vol. 65, nr 1

71--78

EN

This paper presents analysis of selected noise reduction methods used in optical coherence tomography (OCT) retina images (the socalled B-scans). The tested algorithms include median and averaging filtering, anisotropic diffusion, soft wavelet thresholding, and multiframe wavelet thresholding. Precision of the denoising process was evaluated based on the results of automated retina layers segmentation, since this stage (vital for ophthalmic diagnosis) is strongly dependent on the image quality. Experiments were conducted with a set of 3D low quality scans obtained from 10 healthy patients and 10 patients with vitreoretinal pathologies. Influence of each method on the automatic image segmentation for both groups of patients is thoroughly described. Manual annotations of investigated retina layers provided by ophthalmology experts served as reference data for evaluation of the segmentation algorithm.

2

Radial fan controlled with impeller movable blades – CFD investigations

Jóźwik K., Papierski A., Sobczak K., Obidowski D., Kryłłowicz W., Marciniak E., Wróbel G., Marciniak A., Wróblewski P., Kobierska A., Frącczak Ł., Podsędkowski L.

Transactions of the Institute of Fluid-Flow Machinery

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2016

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nr 131

17--40

EN

Modern classical power generation systems, based on power plants in Poland, where coal (hard bituminous coal or lignite) is the primary energy source, operate under variable loading conditions. Thus, all machines working in the technological system of the power generation unit are required to be adapted to variable loading, and, consequently, to operate beyond the design point of their performance characteristics. High efficiency of the process requires the efficiency of individual devices to be high, beyond the design point, as well. For both air and exhaust gases fans, an effective control system is needed to attain a high level of efficiency. As a result of cooperation between two institutes from the Faculty of Mechanical Engineering, Lodz University of Technology, and the Vibroson company, a new design of the radial fan with impeller movable blades, which allows for controlling the device operation within a wide range, has been developed. This new design and determination the performance characteristics for two geometrical variants of blades with computational fluid dynamics methods are presented. The obtained results have been compared to the results of the measurements of fan performance curves conducted on the test stand.

3

Improving Segmentation of 3D Retina Layers Based on Graph Theory Approach for Low Quality OCT Images

Stankiewicz A., Marciniak T., Dąbrowski A., Stopa M., Rakowicz P., Marciniak E.

Metrology and Measurement Systems

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2016

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Vol. 23, nr 2

269--280

EN

This paper presents signal processing aspects for automatic segmentation of retinal layers of the human eye. The paper draws attention to the problems that occur during the computer image processing of images obtained with the use of the Spectral Domain Optical Coherence Tomography (SD OCT). Accuracy of the retinal layer segmentation for a set of typical 3D scans with a rather low quality was shown. Some possible ways to improve quality of the final results are pointed out. The experimental studies were performed using the so-called B-scans obtained with the OCT Copernicus HR device.

4

Optimal dividend policy in discrete time

Marciniak E., Trybuła J.

Demonstratio Mathematica

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2014

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Vol. 47, nr 1

258--270

EN

A problem of optimal dividend policy for a firm with a bank loan is considered. A regularity of a value function is established. A numerical example of calculating value function is given.

5

Linie papilarne i łańcuch DNA

Marciniak E.

LAB Laboratoria, Aparatura, Badania

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2013

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R. 18, nr 2

25-28

6

Odporność korozyjna stopu tytanu Ti6Al4V azotowanego jarzeniowo na potencjale katody i w obszarze plazmy w różnej temperaturze obróbki

Brojanowska A., Popławski K., Tarnowski M., Marciniak E., Sobiecki J. R.

Inżynieria Materiałowa

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2013

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Vol. 34, nr 6

643--646

PL

W artykule analizowano wpływ temperatury w procesie klasycznego azotowania jarzeniowego na potencjale katody i w obszarze plazmy (active screen plasma nitriding) na odporność korozyjną warstw azotowanych wytworzonych na stopie tytanu Ti6Al4V. Do badań wybrano warstwy azotowane wytworzone w dwóch procesach różniących się temperaturą obróbki – 700°C i 800°C. Stwierdzono lepszą odporność korozyjną warstw azotowanych wraz ze wzrostem temperatury obróbki. Wykazano również, że odporność korozyjna warstw azotowanych wytworzonych na stopie tytanu Ti6Al4V w procesie azotowania w obszarze plazmy różni się od odporności korozyjnej warstw uzyskanych w klasycznym procesie azotowania na potencjale katody.

EN

In the paper the influence of temperature of traditional glow discharge nitriding process (cathodic potential) and nitriding in plasma region (active screen plasma nitriding) on corrosion resistance of nitrided layers produced on Ti6Al4V titanium alloy is analyzed. Layers produced in two different nitriding process temperature – 700°C and 800°C – were investigated. Research show that corrosion resistance of nitrided layers enhanced with the process temperature. It is also shown that corrosion resistance of layers produced on Ti6Al4V titanium alloy during plasma nitriding process on cathodic potential differ from those produced during the active screen plasma nitriding process.

7

Study on the kinetics of simultaneous drying and microencapsulation in a spray dryer

Adamiec J., Marciniak E.

Inżynieria Chemiczna i Procesowa

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2006

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T. 27, z. 2

535-546

EN

The paper presents the experimental investigations on the kinetics of simultaneous drying and microencapsulation carried out in a vertical drying tunnel 0.5 m in diameter and 8 m high, equipped with a laser measuring device and a system of sight glasses in the drying chamber to take samples and to measure the parameters of the disperse phase. Drying and microencapsulation of a model system, i.e. the emulsion of sunflower oil in maltodextrin DE16 water solution with the addition of Tween80 emulsifier, have been investigated. At variable drying parameters the kinetics of disperse phase drying in the tunnel and the content of surface and total oil in microcapsules were determined, oil encapsulation degree was calculated, and changes in particle sizes of the disperse phase were measured in cross and longitudinal sections of the tunnel.

PL

Przedstawiono wyniki eksperymentalnych badań kinetyki jednoczesnego suszenia i mikroenkapsulacji w pionowym tunelu suszarniczym o średnicy 0,5 m i wysokości 8 m, wyposażonym w laserową apara-turę pomiarową i system wzierników do pobierania próbek i do pomiaru parametrów fazy rozproszonej w komorze suszenia. Badano suszenie i mikroenkapsulację układu modelowego - emulsję oleju słonecznikowego w wodnym roztworze maltodekstryny DE16 z dodatkiem czynnika emulgującego - Tween80. Wyznaczano kinetykę suszenia fazy rozproszonej w tunelu w różnych warunkach, zawartość oleju powierzchniowego i całkowitego w mikrokapsułkach, obliczano stopień enkapsulacji oleju oraz badano zmiany rozmiaru cząstek fazy rozproszonej mierzonych w przekrojach poprzecznych i podłużnych tunelu.

8

Wykorzystanie zrównoważonej karty wyników w zarządzaniu jakością według wymagań normy ISO 9001:2000

Marciniak E.

Problemy Jakości

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2002

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R. 34, nr 8

8-13

PL

Balanced Scorecard jest systemem pomiaru służącym zarządzaniu strategią przedsiębiorstwa w długim okresie czasu. BSC jest stosowana do realizacji kluczowych procesów.

9

Fuzja przedsiębiorstw - rozwój - opracowanie i wdrożenie Systemu Zarządzania Jakością wg ISO 9001: 2000

Marciniak E., Guntzel P. W.

Problemy Jakości

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2002

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R. 34, nr 3

44-49