Wyniki wyszukiwania - BazTech

1

Automated segmentation of optic disc and optic cup for glaucoma assessment using improved UNET++ architecture

Tulsani Akshat, Kumar Preetham, Pathan Sumaiya

Biocybernetics and Biomedical Engineering

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2021

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Vol. 41, no. 2

819--832

EN

Glaucoma is one of the leading cause of blindness for over 60 million people around the world. Since a cure for glaucoma doesn’t yet exist, early screening and diagnosis become critical for the prevention of the disease. Optic disc and optic cup evaluation are one of the preeminent steps for glaucoma diagnosis. A novel approach is developed in this paper for the identification of glaucoma using a segmentation based approach on the optic disc and optic cup. The Dhristi dataset was used to help improve performance on a small dataset. A custom UNET++ model is built for the segmentation task by tuning the hyperparameters in addition to a custom loss function. The developed loss function helps tackle the class imbalance occurring due to small size of the optic nerve head. The proposed approach achieves 96% accuracy in classifying glaucomatous and non-glaucomatous images based on clinical feature identification. The improvised model is able to achieve state-of-art results for Intersection over Union (IOU) scores, 0.9477 for optic disc and 0.9321 for optic cup, along with providing an enhancement in reducing the training time. The model was tested on publicly available datasets RIM-ONE, DRIONS-DB and ORIGA and is able to achieve an accuracy of 91%, 92% and 90% respectively. The developed approach is validated by training it over RIM-ONE dataset independently, without changing any model parameters. The model provides significant improvement in segmentation of the optic disc and optic cup along with improvement in training time.

2

Robust intensity variation and inverse surface adaptive thresholding techniques for detection of optic disc and exudates in retinal fundus images

Karkuzhali S., Manimegalai D.

Biocybernetics and Biomedical Engineering

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2019

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Vol. 39, no. 3

753--764

EN

Diabetic Retinopathy (DR) is an adverse change in retinal blood vessels leads to blindness for diabetic patients without any symptoms. Diabetes is characterized by imbalance level of glucose in the human body. The optic disc (OD) is the major retinal landmark. Localization of OD is an important step in fundus image analysis and to develop Computer Aided Diagnosis tool for DR. OD center detection is necessary to reduce false positive rate in the detection of exudates (EXs). EXs is the white lesion present in the retina which is the early symptom for the diagnosis of DR. OD is detected using intensity variation algorithm and EXs is segmented using inverse surface adaptive thresholding algorithm. This algorithm achieves better result in localizing OD and segmenting EXs when compared to literature-reviewed methods. The maximum intensity variance method is used to locate OD with average ACC of 96.54%, 98.65%, 98.12%, 99.23%, 99.81% and 98.47% in DIARETDB0, DIARETDB1, MESSIDOR, DRIVE, STARE and Bejan Singh Eye Hospital databases with less computation time of 102 ms, 108 ms, 120 ms, 93 ms, 110 ms and 131 ms. The inverse surface adaptive thresholding method has achieved an SE of 97.43%, 98.87%, 99.12%, 97.21%, 98.72%, and 96.63%, a SPE of 91.56%, 92.31%, 90.21%, 90.14%, 89.58%, 92.56% and an ACC of 99.34%, 99.67%, 98.34%, 98.87%, 99.13%, 98.34% for DIARETDB0, DIARETDB1, MESSIDOR, DRIVE, STARE and Bejan Singh Eye Hospital databases respectively.

3

Robust and accurate optic disk localization using vessel symmetry line measure in fundus images

Panda R., Puhan N. B., Panda G.

Biocybernetics and Biomedical Engineering

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2017

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Vol. 37, no. 3

466--476

EN

Accurate optic disk (OD) localization is an important step in fundus image based computer-aided diagnosis of glaucoma and diabetic retinopathy. Robust OD localization becomes more challenging with the presence of common pathological variations which could alter its overall appearance. This paper presents a novel OD localization method by incorporating salient visual cues of retinal vasculature: (1) global vessel symmetry, (2) vessel component count and (3) local vessel symmetry inside OD region. In the proposed method, a new vessel symmetry line (VSL) measure is designed to demarcate the lines that divide the retinal vasculature into approximately similar halves. The initial OD center location is computed using the highest number of major blood vessel components in the skeleton image. The final OD center localization involves an iterative center of mass computation to exploit the local vessel symmetry in the OD region of interest. The proposed method shows effectiveness in diseased retinas having diverse symptoms like bright lesions, hemorrhages, and tortuous vessels that create potential ambiguity for OD localization. A total of ten publicly available retinal image databases are considered for extensive evaluation of the proposed method. The experimental results demonstrate high average OD detection accuracy of 99.49%, while achieving state-of-the-art OD localization error in all databases.

4

Ways for creation of long-term digital data storage carriers

Petrov V.V.

Pomiary, Automatyka, Komputery w Gospodarce i Ochronie Środowiska

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2010

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nr 3

25-27

EN

An analysis of possibilities of using different types of carriers for providing long-term information storage is conducted. Great possibilities of optical recording/reproducing carriers for realization of long-term and reliable information storage are demonstrated. Directions of improving characteristics of optical data disk carriers for more complete fulfilling requirements, which specify carriers for long-term digital information storage, are determined.

PL

Przeprowadzona jest analiza możliwości używania różnych typów nośników do zapewnienia długoterminowego przechowywania informacji. Zademonstrowane są duże możliwości optycznego nagrywania/ odtwarzania nośników w celu realizacji długotrwałego i rzetelnego przechowywania informacji. Określone są też wskazówki do poprawy cech charakterystycznych optycznych nośników dysków z danymi dla jeszcze kompletniejszego spełnienia wymagań które wyróżniają nośniki do długotrwałego przechowywania cyfrowych informacji.

5

Information security and problems of long-term storage of electronic documents

Petrov V., Gorbulin V., Kryuchyn A.

Pomiary, Automatyka, Komputery w Gospodarce i Ochronie Środowiska

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2009

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nr 1

6-8

EN

Realization of reliable long-term storage of strategically important information, bank information and others like that, possibilities of fast access to it is one of foreground tasks, solution of which is necessary for providing information security ond different levels both national and regional ones. Opportunities are analyzed and ways for creation of long-term data storage carriers are determined.

PL

Wykorzystanie wiarygodnych, długoterminowych, strategicznie ważnych przechowywanych informacji, informacji bankowych i innych, możliwości szybkiego dostępu do nich są jednym z zadań, których rozwiązanie jest konieczne dla zapewnienia bezpieczeństwa informacji na różnych poziomach zarówno krajowych jak i regionalnych. Analizowane i określane są możliwości i sposoby tworzenia długoterminowych nośniki danych.

6

Blaski i cienie elektronicznej archiwizacji

Maślana R.

Informatyka

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1998

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nr 12

37-41

PL

Archiwizacja elektroniczna wydaje się skomplikowana, kosztowna i pracochłonna. Mało kto uświadamia sobie, jakie korzyści przynosi takie archiwum.