541 research outputs found

    Markov Chain Modeling of Daily Rainfall in Lay Gaint Woreda, South Gonder Zone, Ethiopia

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    Information on seasonal Kiremet and seasonal Belg rainfall amount is important in the rain fed agriculture of Ethiopia since more than 85% of the population is dependent on agriculture particularly on rain fed farming practices. The distribution pattern of rainfall rather than the total amount of rainfall within the entire period of time is more important for studying the pattern of rainfall occurrence. A two-state Markov chain was used to describe the characteristics of rainfall occurrences in this woreda. The states, as considered were; dry (d) and rainy (r). The overall chance of rain and the fitted curve tells us that the chance of getting rain in the main rainy season is about twice as compared to the small rainy season. The first order Markov chain model indicates that the probability of getting rain in the small rainy season is significantly dependent on whether the earlier date was dry or wet. While the second order Marko chain indicates that the main rainy season the dependence of the probability of rain on the previous two dates\u27 conditions is less as compared with the small rainy season. Rainfall amounts are very variable and are usually modeled by a gamma distribution. Therefore, the pattern of rainfall is somewhat unimodial having only one extreme value in August. Onset, cessation and length of growing season of rainfall for the main rainy season show medium variation compared to the small rainy season

    Building A High-Resolution Vegetation Outlook Model to Monitor Agricultural Drought for the Upper Blue Nile Basin, Ethiopia

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    To reduce the impacts of drought, developing an integrated drought monitoring tool and early warning system is crucial and more effective than the crisis management approach that is commonly used in developing countries like Ethiopia. The overarching goal of this study was to develop a higher-spatial-resolution vegetation outlook (VegOut-UBN) model that integrates multiple satellite, climatic, and biophysical input variables for the Upper Blue Nile (UBN) basin. VegOut-UBN uses current and historical observations in predicting the vegetation condition at multiple leading time steps of 1, 3, 6, and 9 dekades. VegOut-UBN was developed to predict the vegetation condition during the main crop-growing season locally called “Kiremt” (June to September) using historical input data from 2001 to 2016. The rule-based regression tree approach was used to develop the relationship between the predictand and predictor variables. The results for the recent historic drought (2009 and 2015) and non-drought (2007) years are presented to evaluate the model accuracy during extreme weather conditions. The result, in general, shows that the predictive accuracy of the model decreases as the prediction interval increases for the cross-validation years. The coefficient of determination (R2) of the predictive and observed vegetation condition shows a higher value (R2 \u3e 0.8) for one-month prediction and a relatively lower value (R2 = 0.70) for three-month prediction. The result also reveals strong spatial integrity and similarity of the observed and predicted maps. VegOut-UBN was evaluated and compared with the Standardized Precipitation Index (SPI) (derived from independent rainfall datasets from meteorological stations) at different aggregate periods and with a food security status map. The result was encouraging and indicative of the potential application of VegOut-UBN for drought monitoring and prediction. The VegOut-UBN model could be informative in decision-making processes and could contribute to the development of operational drought monitoring and predictive models for the UBN basin

    Geospatial forecast model for tsetse-transmitted animal trypanosomosis in Ethiopia

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    The aims of this study were to develop a geographic information systems (GIS) forecast and risk assessment model for cyclically transmitted trypanosomosis in Ethiopia by matching features in the environment to available information on the preferences and limits of tolerance of the parasite and its vector, and validate and further develop the GIS model using data from current and historical prevalence survey data and habitat microenvironment studies from trypanosomosis endemic areas. Results indicate that GIS model developed for parasitic diseases based on growing degree day (GDD) concept can be applied to tsetse-transmitted trypanosomosis. GIS for animal trypanosomosis was created using Food and Agriculture Organization – Crop Production System Zones (FAO-CPSZ) database and Normalized Difference Vegetation Index (NDVI) and maximum temperature (Tmax) from the Global Land 1km dataset. The two datasets used to determine the risk of tsetse flies and consequently animal trypanosomosis in Ethiopia indicated the magnitude of the disease and possible expansion of the “fly belt” in the future. The GIS model indicated the distribution and importance of tsetse-transmitted trypanosomosis in Ethiopia. Spatial and statistical analysis verified the use of GDD concept and climate forecast system that was developed to determine the suitability of a given environment for the proliferation of a biotype, in this case tsetse and trypanosomes. Results presented here indicate the importance of GDD and the two climatic variables (NDVI and Tmax) in the development of forecast model for tsetse-transmitted trypanosomosis in Ethiopia. Key words/phrases: Ethiopia, GIS, NDVI, Tmax, trypanosomosis SINET: Ethiopian Journal of Science Vol.27(1) 2004: 1-

    Effect of curing conditions and harvesting stage of maturity on Ethiopian onion bulb drying properties

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    The study was conducted to investigate the impact of curing conditions and harvesting stageson the drying quality of onion bulbs. The onion bulbs (Bombay Red cultivar) were harvested at three harvesting stages (early, optimum, and late maturity) and cured at three different temperatures (30, 40 and 50 oC) and relative humidity (30, 50 and 70%). The results revealed that curing temperature, RH, and maturity stage had significant effects on all measuredattributesexcept total soluble solids

    Improvement of Grassland Through Community Participation in the Middle AwashValley of Ethiopia

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    The natural resources of the grassland in the middle Awash valley of Ethiopia are subjected to competing claims: development to generate revenue for the state, conservation of wildlife and wilderness areas, as well as use for local production. The combination of climatic conditions causing drought and the over use of the natural resource can be cited as the primary cause of grassland deterioration in the area. Since the problems of the grasslands are complex and multi-dimensional, they are not amenable to quick and easy fixes. Hence, if sustainable progress is to be achieved, the responsibility for change must be in the hands of the communities and household themselves. Pastoral communities, in collaboration with CARE-Ethiopia, local government and other partner NGOs embarked on grassland improvement activities that were based on traditional activities. The objective of this study was to assess the condition of the traditionally-improved grazing lands

    Analysis and sourcing of the mechanical equipment required for a ceramic pot filter production facility

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    Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 118).Research was done into identifying and sourcing the mechanical equipment required for manufacturing ceramic pot filters, specifically for use in the Pure Home Water factory in Northern Ghana. The pieces of equipment identified were a hammer mill, a mixer, a pug mill, and a mechanical press with molds for pressing the filters. Evaluative criteria for each machine were developed, and machines available from manufacturers and machines produced locally were evaluated based on these criteria. Several machines fit the evaluative criteria and were recommended for the Pure Home Water facility. The Meadows Model 5 hammer mill was recommended for purchase from the manufacturer. Of the mixers researched, the mixer made by RDI-C, the Bluebird 24S mixer, and the mixer designed by Prof. Manny Hernandez all satisfy the requirements of Pure Home Water. The pug mill recommended for Pure Home Water was the Venco 75mm pug mill. The Mani Press and the paraboloid molds were also recommended for the Pure Home Water facility.by Julian Getachew.S.B

    Management of undescended testes: a retrospective study from a tertiary hospital in Ethiopia

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    Background: Undescended testis is one of the commonest congenital malformations seen in boys. The aim of this study is to evaluate the pattern of presentation, approach to diagnosis, treatment and follow up in Tikur Anbesa Specialized Hospital, a tertiary teaching hospital in Ethiopia.Methods: This is a retrospective cross sectional study of all boys with undescended testis operated in Tikur Anbesa Specialized Hospital between September 2012 and August 2014.Results: Of 82 boys operated within the study period, 66 boys with 78 undescended testes are studied. Twenty-six percent (17/66)came before the age of 2 years, while the majority of the study group, 50% (33/66), presented beyond 5 years of age. Of the 17 boys brought to the hospital before 2 years, only 41% (7/17) them were treated before the age of two years. The majority 89% (59/66) of the boys were treated after 2 years of age. Seventy-one testes of 78 [91%] were in the inguinal canal, 5 were intra-abdominal and 2 were absent. 46% (36/78) were on the left side, 29% (23/78) on the right side and the rest were bilateral. Among the 54 boys who had ultrasound examination, the ultrasound report is consistent with operative findings in 33 [61%]. Associated congenital malformations were found in 31.8% (21/66) of the boys. Hypospadia was the predominant malformation comprising 38% (8/21) of the total congenital malformations. Orchidopexy was done for 82% (64/78) of the total testes, orchiectomy was done for 9% (7/78) and biopsy was taken in 1 case. Among the total operated boys only 62% (41/66) were followed in our clinic; of those who had follow up 10% (4/41) testes atrophied and 1 [2%] testis retracted.Conclusion: Boys with undescended testes present and are treated late in Tikur Anbesa Hospital. As opposed to the literatures most of the undescended testes were found on the left side. Ultrasound examination cannot be the only mode of examination for undescended testes as it misses more than one third of the cases. Hypospadia is the commonest associated congenital malformation. Post operative follow up is very poor after treatment for undescended teste

    Health Extension Workers' diagnostic accuracy for common childhood illnesses in four regions of Ethiopia: a cross-sectional study.

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    AIM: The Ethiopian primary care of sick children is provided within the integrated Community Case Management of childhood illnesses by Health Extension Workers (HEW). There is limited knowledge whether this cadre correctly assess and classify common diseases. The aim was to study their ability to correctly classify common childhood illnesses. METHODS: A survey was conducted from December 2016 to February 2017 in four regions of Ethiopia. Observations of the HEWs' assessment and classification of sick children were followed by child re-examination by a trained health officer. RESULTS: The classification by the HEWs of 620 sick children as compared to the re-examiner had a sensitivity of 89% and specificity of 94% for diarrhoea, sensitivity 52% and specificity 91% for febrile disorders, and a sensitivity of 59% and specificity of 94% for acute respiratory tract infection. Malnutrition and ear infection had a sensitivity of 39 and 61%, and a specificity of 99 and 99%, respectively. CONCLUSION: Most cases of diarrhoea were correctly classified, while other illnesses were not frequently identified. The identification of malnutrition was especially at fault. These findings suggest that a significant number of sick children were undiagnosed that could lead to absent or incorrect management and treatment
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