Wyniki wyszukiwania - Biblioteka Nauki

1

Estimation of severity level of non-proliferative diabetic retinopathy for clinical aid

100%

Kaur J. , Mittal D.

Biocybernetics and Biomedical Engineering

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2018

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tom Vol. 38, no. 3

708--732

EN

Diabetic retinopathy, a symptomless complication of diabetes, is one of the significant causes of vision impairment in the world. The early detection and diagnosis can reduce the occurrence of severe vision loss due to diabetic retinopathy. The diagnosis of diabetic retinopathy depends on the reliable detection and classification of bright and dark lesions present in retinal fundus images. Therefore, in this work, reliable segmentation of lesions has been performed using iterative clustering irrespective of associated heterogeneity, bright and faint edges. Afterwards, a computer-aided severity level detection method is proposed to aid ophthalmologists for appropriate treatment and effective planning in the diagnosis of non-proliferative diabetic retinopathy. This work has been performed on a composite database of 5048 retinal fundus images having varying attributes such as position, dimensions, shapes and color to make a reasonable comparison with state-of-the-art methods and to establish generalization capability of the proposed method. Experimental results on per-lesion basis show that the proposed method outperforms state-of-the methods with an average sensitivity/specificity/accuracy of 96.41/96.57/94.96 and 95.19/96.24/96.50 for bright and dark lesions respectively on composite database. Individual per-image based class accuracies delivered by the proposed method: No DR-95.9%, MA-98.3%, HEM-98.4%, EXU-97.4% and CWS-97.9% demonstrate the clinical competence of the method. Major contribution of the proposed method is that it efficiently grades the severity level of diabetic retinopathy in spite of huge variations in retinal images of different databases. Additionally, the substantial combined performance of these experiments on clinical and open source benchmark databases support a strong candidature of the proposed method in the diagnosis of non-proliferative diabetic retinopathy.

2

A generalized method for the detection of vascular structure in pathological retinal images

100%

Kaur J. , Mittal D.

Biocybernetics and Biomedical Engineering

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2017

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tom Vol. 37, no. 1

184--200

EN

Variations in blood vasculature morphology of retinal fundus images is one of the dominant characteristic for the early detection and analysis of retinal abnormalities. Therefore the accurate interpretation of blood vasculature is useful for ophthalmologists to diagnose patients that suffer from retinal abnormalities. A generalized method to detect and segment blood vasculature using retinal fundus images has been proposed in this work using (i) preprocessing for quality improvement of retinal fundus images, (ii) initial segmentation of vasculature map to find vascular and non vascular structures, (iii) extraction of relevant set of geometrical based features from the vasculature map and intensity based features from original retinal fundus image that differentiate vascular and non vascular structures efficiently, (iv) supervised classification of vascular and non vascular structures using the extracted features, and (v) joining of candidate vascular structures to create connectivity. The proposed method is evaluated on clinically acquired dataset and different publically available standard datasets such as DRIVE, STARE, ARIA and HRF. The clinically acquired dataset consists of 468 retinal fundus images comprising of healthy images, images with mild, intermediate and severe pathologies. Test results of the proposed method shows average sensitivity/specificity/accuracy of 85.43/97.94/95.45 on the 785 retinal fundus images. The proposed method shows an improvement of 14.01% in sensitivity without degrading specificity and accuracy in comparison to the recently published methods.

3

Unique fuzzy optimal value of fully fuzzy linear programming problems

100%

Kaur J. , Kumar A.

Control and Cybernetics

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2012

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tom Vol. 41, no. 2

497-508

EN

Kumar, Kaur and Singh (2011), proposed a new method to find the exact fuzzy optimal solution of fully fuzzy linear programming (FFLP) problems with equality constraints. In this paper, an FFLP problem is chosen to show that the fuzzy optimal value, obtained by using the existing method, is not necessarily a unique fuzzy number i.e., the fuzzy optimal value of the FFLP problem, obtained by the existing method, does not conform to the uniqueness property of fuzzy optimal value. To overcome this shortcoming of the existing method, a new method is proposed for solving FFLP problems with equality constraints. To show the advantage of the proposed method the results of the chosen FFLP problem, obtained by using the existing and the proposed methods, are compared.

4

A generalized method for the segmentation of exudates from pathological retinal fundus images

100%

Kaur J. , Mittal D.

Biocybernetics and Biomedical Engineering

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2018

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tom Vol. 38, no. 1

27--53

EN

Diabetic retinopathy, an asymptomatic complication of diabetes, is one of the leading causes of blindness in the world. The exudates, abnormal leaked fatty deposits on retina, are one of the most prevalent and earliest clinical signs of diabetic retinopathy. In this paper, a generalized exudates segmentation method to assist ophthalmologists for timely treatment and effective planning in the diagnosis of diabetic retinopathy is developed. The main contribution of the proposed method is the reliable segmentation of exudates using dynamic decision thresholding irrespective of associated heterogeneity, bright and faint edges. The method is robust in the sense that it selects the threshold value dynamically irrespective of the large variations in retinal fundus images from varying databases. Since no performance comparison of state of the art methods is available on common database, therefore, to make a fair comparison of the proposed method, this work has been performed on a diversified database having 1307 retinal fundus images of varying characteristics namely: location, shapes, color and sizes. The database comprises of 649 clinically acquired retinal fundus images from eye hospital and 658 retinal images from publicly available databases such as STARE, MESSIDOR, DIARETDB1 and e-Optha EX. The segmentation results are validated by performing two sets of experiments namely: lesion based evaluation criteria and image based evaluation criteria. Experimental results at lesion level show that the proposed method outperforms other existing methods with a mean sensitivity/specificity/accuracy of 88.85/96.15/93.46 on a composite database of retinal fundus images. The segmentation results for image-based evaluation with a mean sensitivity/specificity/accuracy of 94.62/ 98.64/96.74 respectively prove the clinical effectiveness of the method. Furthermore, the significant collective performance of these experiments on clinically as well as publicly available standard databases proves the generalization ability and the strong candidature of the proposed method in the real-time diagnosis of diabetic retinopathy.

5

Goezia (Goezia) alii sp. n. (Nematoda) from a freshwater fish, Channa stratus (Bloch), from Ludhiana (Punjab, India), and revision of the genus

100%

Kaur J. , Khera S.

Acta Parasitologica Polonica

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1991

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tom 36

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nr 1

6

Phonetic study of voiced and voiceless stops in Hindi

80%

Juglan K. C. , Kaur J. , Upadhyay R. K.

International Journal of Applied Mechanics and Engineering

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2011

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tom Vol. 16, no 3

661-670

EN

This paper presents findings from a phonetic study of voiced and voiceless stops. To distinguish voiced and voiceless stops, we have to measure three parameters, namely the vowel length, duration of CVC syllables and voice onset time (VOT) of the word-initial consonants. For measuring the vowel length and gap duration, we considered 10 voiced (/b, d, d., g, d3/) and voiceless (/p, t, t., k, t /) stop consonants and two abutted vowels /a/ and /i/. For measuring voice onset time, we considered 3 voiced (/b, d., g/) and voiceless (/p, t., k/) stop consonants. These sounds were recorded with the help of GOLDWAVE software in the sound proof lab at C-DAC (Centre for Development of Advanced Computing), NOIDA. The utterances were acoustically analyzed via PRAAT. The values of target stops were obtained from the waveform and verified with the spectrogram. The wide band spectrograms and text grids were plotted by using "PRAAT" software.

7

Spectral fingerprinting revealed modulation of plant secondary metabolites in providing abiotic stress tolerance to invasive alien plants Lantana camara (L.), Parthenium hysterophorous (L.), Ricinus communis (L.), and Ageratum conyzoides (L.) (plant metabolites in stress tolerance to invasive plants)

80%

Sharma A. D. , Kaur J. , Chand T. S. P.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

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2021

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tom 102

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nr 3

8

Evaluation of the thermo-mechanical and explosive properties of bimodal and hybrid polymer bonded explosive (PBX) compositions based on HNS and HMX

80%

Kaur J. , Arya V. P. , Kaur G. , Lata P.

Central European Journal of Energetic Materials

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2013

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tom Vol. 10, no. 3

371--391

EN

In the present paper, a series of bimodal PBX compositions containing coarse (90 μm) and fine (<1 μm) HNS (2,2’4,4’6,6’-hexanitrostilbene) and hybrid PBX compositions based on HNS and HMX (1,3,5,7-tetranitro-1,3,5,7- tetraazacyclooctane) in varying mass ratios, along with the fluoropolymer Viton-A, a vinylidene fluoride and hexafluoropropylene copolymer, as a binder (5%), have been prepared on the lab scale. In order to observe any effect of incorporating fine HNS particles with coarse ones and the effect of replacing HNS with HMX in all types of bimodal and hybrid PBX compositions, the samples were characterized for composition analysis, thermal behavior and morphological analysis as well as evaluated for their mechanical and explosive properties including sensitiveness tests and detonic properties. The data showed that incorporation of fine HNS into coarse particles of HNS in the bimodal PBX resulted in an increase in mechanical strength and a decrease in friction and impact sensitivity, as well as an enhanced performance compared to PBXs based on coarse HNS alone. Viton-A based hybrid PBX compositions provided better mechanical and sensitivity properties as compared to conventional explosive compositions based exclusively on HMX or HNS and the performance of the PBX compositions increased with increasing HMX content.

9

Biochemical mapping of lentil (Lens culinaris Medik) genotypes for quality traits

70%

Ahuja H. , Kaur S. , Gupta A. K. , Singh S. , Kaur J.

Acta Physiologiae Plantarum

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2015

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tom 37

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nr 09

EN

Six genotypes and thirty-eight advance breeding lines of lentil (Lens culinaris Medik.) were evaluated for carbohydrate composition, soluble proteins, mineral content and antinutritional traits such as phenolic compounds, tannins, trypsin inhibitors, saponins and phytic acid. The average content of total sugars, starch and proteins was found to be 47.18, 421.2, 236.24 mg/g, respectively. Lentil genotypes contained higher content of iron, followed by zinc and the least content of copper. The content of bound fructose, phytic acid, tannins and phenols showed significant variation in lentil genotypes. Seven genotypes namely LL-1277, LL-1302, LL-1306, LL-1310, LL-1317, LL-1325 and L-4147 have low phytic acid content and are nutritionally good. LL-1231, LL-1305 and LL- 1317 had higher content of both zinc and iron as well as protein content. LL-1328 could be important for pest resistance due to presence of higher trypsin inhibitor activity. Antioxidant potential of these genotypes estimated on the basis of free radical scavenging activity (DPPH), ferric reducing antioxidant power (FRAP), total reducing power, hydroxyl radical scavenging activity, superoxide anion radical scavenging activity and nitric oxide radical scavenging activity showed significant variation among genotypes. Thirteen genotypes (LL-699, LL-1209, LL- 1223, LL-1277, LL-1279, LL-1302, LL-1304, LL-1306, LL-1309, LL-1311, LL-1315, LL-1321, LL-1325) showed high antioxidant activity. Advance breeding lines namely LL-1161, LL-1221, LL-1313, LL-1325, L-4147 are nutritionally important with high protein content, low/medium antinutritional factors, high antioxidant potential and good yield.