http://ir.haramaya.edu.et//hru/handle/123456789/3 2026-10-28T12:58:02Z 2026-10-28T12:58:02Z Abdurezak Mohammed Yusuf Berhanu Mengistu (PhD) Haftu Brhane Gebremichael (PhD) http://ir.haramaya.edu.et//hru/handle/123456789/8722 2026-10-19T07:50:16Z 2024-04-01T00:00:00Z

VARIABILITY AND CHANGE OF RAINFALL, TEMPERATURE, AND RAINFALL TELECONNECTION WITH PACIFIC OCEAN SEA SURFACE TEMPERATURE IN EASTERN HARARGHE Abdurezak Mohammed Yusuf; Berhanu Mengistu (PhD); Haftu Brhane Gebremichael (PhD) For thousands of years, the world's climate has been changing, and it is real, with serious consequences, notably in the water sector, which is essentially vulnerable. Climate variability is erratic, shifting unpredictably at the global, regional, and local levels. Knowledge of past climatic variability at local and regional scales can help build adaptation methods. As a result, a study was carried out and developed to examine changes, variability of rainfall, temperature, and its teleconnection with Pacific Ocean Sea surface temperature in Eastern Hararghe, Ethiopia using the CFSR dataset. The study is based on gridded CFSR rainfall and temperature data from 1983 to 2021 and 1983 to 2020 respectively. The spatial trend, variability, and distribution of rainfall and temperature were examined using ArcGIS 10.5 software. Mann-Kendall (MK) and Sen's slope estimator trend tests were also employed to analyze rainfall and temperature trends of change and anomaly. Correlation analysis was used to examine the relationship between seasonal rainfall with Pacific Ocean Sea surface temperature. The findings in the Eastern Hararghe zone show that the dry season (Bega) has higher seasonal fluctuation and the short rainy season (Belg) has higher variability. Rainfall trends declined significantly in most areas except the northernmost tip, but increased in Bega, particularly in the central region. NINO 3.4 SST had a decreasing effect on Kiremt season rainfall, while equatorial Pacific Ocean SST decreased rainfall. Droughts were generally connected with ENSO episodes in the study area. The study also found that the eastern half of the Eastern Hararghe experienced a significant increase in seasonal maximum temperatures, with the eastern section experiencing the largest increase. This raises concerns about potential drought and the need for increased attention to identify temperature extremes. The study also found that the typical seasonal maximum temperature has been higher than its minimum temperature over the last 38 years. Overall, the unpredictable rainfall, rising temperatures, and the biggest regional variance seen in the zone indicate that the area's agricultural sector is vulnerable and that all actors must work together to save agriculture output in Ethiopia's Eastern Hararghe Zone. To create an effective climate change adaptation strategy, it is vital to first analyze the current effects of climate on economic growth as well as extreme events. The study suggests further research on future climatic variability, temperature extremes, and human intervention in the Zone using various data sources, including CFSR grid data. 57p.

2024-04-01T00:00:00Z Assemahgn, Wondwosun http://ir.haramaya.edu.et//hru/handle/123456789/8700 2026-06-22T07:34:39Z 2019-07-01T00:00:00Z

The Central Field Approximation for Many Electron Atoms Assemahgn, Wondwosun The solution to the Schrodinger equation in case of Hydrogen atom (single particle) can be solved exactly. But if we consider many electron atoms the Schrodinger equation could not solved exactly due to the electron-electron term makes the solution inseparable in single-particle coordinates. However, we can estimate the solutions using different methods. so from those methods the Central Field Approximation provides an excellent starting point to deal with a many-electron system and even if further improvements on this are available and often employed, the Central Field Approximation scheme itself serves a very large number of applications. A set of Quantum defect were also performed and the results have been compared with that of the experimental values. the term quantum defect is a measure of the difference betwen an energy level and the corresponding one in hydrogen. That is the extent to which an outer (valence) electron of a given angular momentum penetrates the inner shell of the atom. While comparing the experimental and calculated values, we have stressed the role of centeral field approximation in Quantum defect theory, some suggestions for improvement of the results are also disscussed 62

2019-07-01T00:00:00Z Lata, Teshale http://ir.haramaya.edu.et//hru/handle/123456789/8693 2026-06-22T07:11:29Z 2024-06-01T00:00:00Z

Classification Of Jimma Coffee Beans Using Morphological and Color Features Lata, Teshale Image processing techniques have become increasingly useful in the vegetable industry, especially for applications in quality inspection and evaluation of food grains, fruits, vegetables, processed foods, and defect sorting. In this research work, we focused on the classification of Jimma coffee beans using morphological features (Limmu, Abba Buna, Yachi, and Buno wash), color, and morphological features extracted from 600 images. For each category, 150 images were captured. We used Artificial Neural Networks (ANN) to classify Jimma coffee beans based on the extracted features. Specifically, 15 color features and 8 morphological features, totaling 23 predominant features, were extracted from images of the four classes of coffee beans. We implemented a three-classification setup using color, morphology, and a combination of color and morphological datasets as inputs to the network. For the dataset considered, we allocated 70% (420 images) for training, 20% (120 images) for testing, and 10% (60 images) for validation. The accuracy of classification using color, morphology, and their combination were 74.8%, 75.0%, and 74.8%, respectively. The performance of the network was optimal for all classifications 67

2024-06-01T00:00:00Z Dejene Gurme Zekeria Yusuf (PhD) Mulugeta Desta (PhD) http://ir.haramaya.edu.et//hru/handle/123456789/8682 2026-06-22T06:30:02Z 2025-11-01T00:00:00Z

MICROBIAL QUALITY AND HYGIENIC PRACTICES OF SELECTED FRESH FRUIT JUICES IN HARAR CITY, EASTERN ETHIOPIA Dejene Gurme; Zekeria Yusuf (PhD); Mulugeta Desta (PhD) Freshly prepared fruit juices are widely consumed in urban centers of Ethiopia due to their nutritional value, affordability, and accessibility. However, their microbiological safety remains a growing public health concern, particularly when juices are prepared under poor hygienic conditions. This study assessed the microbial quality and hygienic practices associated with mango (Mangifera indica) and avocado (Perseaamerican)juices vended in Harar city. A total of 20 juice samples (10 Mango and 10 Avocado) were collected from local juice houses such as Addot, Selam, Silase, TeshitaJuice, and Berger house between April and May 2022. Standard culture-based methods were employed to enumerate indicator organisms (total coliforms, fecal coliforms, Escherichia coli) and spoilage microbes (yeasts, molds, Staphylococcus species), and to detect selected pathogens (E. coli, Staphylococcus aureus, Salmonella, and Shigella). Additionally, a structured questionnaire was administered to 30 vendors and consumers to assess socio-demographic characteristics, awareness, and hygienic practices. Data was analyzed using descriptive statistics and chi-square tests. Results showed that both mango and avocado juices were contaminated with coliforms, E. colicounts ranging from 2.42 ± 0.05 to2.77 ± 0.08 log₁₀ cfu/mL. Staphylococcal counts were significantly higher in avocado juices (4.97 ± 0.15 log₁₀ cfu/mL) than in mango (4.30 ± 0.12 log₁₀ cfu/mL, p ≤ 0.05). Yeasts and molds exceeded Codex limits (≤3 log₁₀ cfu/mL) in all samples. Pathogen prevalence included E. coli (30% of samples), S. aureus (40–50%), Salmonella (10–20%), and Shigella (20% in avocado only). All juice samples failed to meet Codex microbiological standards, indicating potential health risks to consumers. Survey data revealed that most respondents were young (67% aged 21–23 years), lacked formal training in food hygiene (83%), and relied exclusively on untreated tap water during preparation.Hence, freshly prepared mango and avocado juices sold in Harar are unsafe for consumption due to high microbial loads and the presence of pathogens. So, it needs urgent interventions on food hygiene training for vendors, stricter regulatory monitoring, improved water quality, and consumer awareness campaigns to safeguard public health 48p.

2025-11-01T00:00:00Z