Browsing by Author "Moges, Daniel"

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    An Automated Segmentation at Retinal Images for Use in Diabetic Retinopathy Studies
    (Addis Ababa University, 2014-10) Moges, Daniel; Assefa, Dawit (PhD.)
    Automated computer aided detection of retinal lesions associated with Diabetic Retinopathy (DR) offers many potential benefits. In a screening setting, it allows the examination of large number of images in less time and more objectively than traditional observer driven techniques. In a clinical setting, it can be an important diagnostic aid by reducing the workload of trained graders and other costs. However, the segmentation of major pathological structures and their subsequent follow–ups are not easy because of various artifacts such as presence of anatomical structures with highly correlated pixels with that of lesion, illumination variability, noise and movement of the eye during multiple visits by the patient. This study presents a novel mathematical scheme for analysis of color retinal images acquired through digital fundus cameras from patients treated for DR. The proposed scheme uses a holistic representation of the color images in the three (trinion) space and applies trinion based Fourier transforms to extract useful imaging features for the purpose of classification and segmentation of retinal images. A suitable color space transformation and a way of extracting robust higher order features are included in the method. The scheme has been applied in analyzing images acquired from standard retinal image databases. Results have showed that the algorithm achieved 86.06% sensitivity, 96.06% specificity, and 92.65% accuracy for pixel base segmentation of Hard Exudates (HEs) the most prevalent lesions that appears in the earliest stages of DR, while it achieved 96.67% sensitivity, 100% specificity and 97.3% accuracy for image base classification of abnormalities due to DR.
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    Facebook Usage Habit off the Youth:: Challenges and Opportunities on Spiritual Activities
    (Addis Ababa University, 2019-06) Moges, Daniel; Abdiisa, Amanual ( Assistant Professor)
    This study aims at examining how and why Sunday school students use facebook and its related challenges and opportunities. Three communication theories—media dependency theory, the use and gratification theory and technology determinism theory are also considered in the findings of this research. The study employed both qualitative and quantitative methods. For the qualitative method both participant and non- participant observation were used. For quantitative method, survey was used as a data gathering tool. The survey questionnaire was administered to 178 people selected through non-random sampling through convenience and snowball sampling methods. SPSS software is used to analyze the data gathered. The analysis of the data reveals that spiritual youth use facebook for both socialization and spiritual purposes. Despite these opportunities, these youth are facing challenges in using facebook like wasting time, weaken their spiritual activities and addiction. Many spiritual youth also do not worry about whether their posts create any risk or not. This may be the future challenge of the spiritual youth and the church. Based on the finding recommendations are suggested. Of these, the researcher suggests that the spiritual institutions should work together with the government in preparing workshops and seminars in an ongoing manner on how the youth use the social media and in how to design a curriculum and social media usage policy to teach and show the youths on the challenges and opportunities of the social media.