89 research outputs found

    Analysis of Seed Potato Systems in Ethiopia

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    This study aimed to analyze the seed potato systems in Ethiopia, identify constraints and prioritize improvement options, combining desk research, rapid appraisal and formal surveys, expert elicitation, field observations and local knowledge. In Ethiopia, informal, alternative and formal seed systems co-exist. The informal system, with low quality seed, is dominant. The formal system is too small to contribute significantly to improve that situation. The informal seed system should prioritize improving seed quality by increasing awareness and skills of farmers, improving seed tuber quality of early generations and market access. The alternative and formal seed systems should prioritize improving the production capacity of quality seed by availing new varieties, designing quality control methods and improving farmer’s awareness. To improve overall seed potato supply in Ethiopia, experts postulated co-existence and linkage of the three seed systems and development of self-regulation and selfcertification in the informal, alternative and formal cooperative seed potato systems. Resumen Este estudio tuvo el propósito de analizar los sistemas de producción de papa en Etiopia, identificar limitantes, y priorizar opciones de mejorar, mediante la combinación de investigación de escritorio, apreciaciones rápidas y estudios formales, encuestas a expertos, observaciones de campo y conocimiento local. En Etiopia co-existen sistemas de semilla informal, alternativo y formal. Domina el sistema informal, con baja calidad de semilla. El sistema formal es muy pequeño como para contribuir significativamente al mejoramiento de esa situación. El sistema informal de semilla debería tener como prioridad el mejoramiento en la calidad de la semilla mediante el aumento en la atención y habilidades de los productores, mejorando la calidad de la semilla-tubérculo de las generaciones tempranas y el acceso al mercado. Los sistemas alternativo y formal de semilla deberían priorizar el mejoramiento en la capacidad de producción de semilla de calidad, mediante la validación de nuevas variedades, el diseño de métodos de control de calidad, y mejorando la atención del productor. Para mejorar el suministro general de semilla de papa en Etiopia, los expertos postularon la co-existencia y asociación de los tres sistemas de semillas y el desarrollo de autorregulación y autocertificación en los sistemas cooperativos de semilla de papa informal, alternativo y formal. Keywords Potato . Seed quality . Seed tuber . Seed system . Quality improvement . Expert elicitation . Solanum tuberosum Introductio

    Feed marketing in Ethiopia: results of rapid market appraisal

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    Despite the large livestock population in Ethiopia, the sector’s contribution at the micro or macro level is well below its potential due to various reasons, notably feed shortage and diseases, compounded by inefficiencies in the livestock input and output markets. Feed marketing studies are scarce in Ethiopia. This study is aimed at assessing the feed marketing system in Ethiopia to generate a general understanding of the feed supply and demand characteristics, feed marketing, feed prices, market places, market actors, and market institutions. The types of fodder supplied in the country differ from place to place depending on the type of crops grown as conditioned by the agro-climatic conditions. Buyers and sellers have various perceptions about the quality of the fodder supplied to the market. There are competing uses of crop residues and hay in Ethiopia. Crop residues and hay are transported in a variety of ways. Most of the crop residues are retailed in the open market. Hay is mostly sold in situ. Agro-industrial by-products from flour and edible oil mills, grind mills and local brewery are sold in all of the study areas. There are about 15 feed mixers and millers in the country as observed during the study period. However, only five of them are manufacturing purely for sale; others produce for own consumption and to sell surpluses. Feed prices are rising sharply. Available price data indicated that there are significant price differences between farm gate and wholesale prices of crop residues and hay. Among the crop residues teff straw is most expensive. Among agroindustrial by-products, linseed cake is most expensive, followed by cotton seed cake. Most of the feed trading is informal. Implications to improve the feed marketing system are drawn

    Dynamic analysis of spur gear with backlash using ADAMS

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    Gear tooth profile can deviate from its initial design shape and size as a result of increasing service time under time-varying load, introducing external agents like debris, overheating due to friction, wear, and in generally due to other nonlinear factors such as backlash. As a result, the dynamics of the gear will also vary depending on the resulting gear tooth profile. In this study, the worn-out gear tooth is modelled as a backlash by assuming a uniformly distributed worn out surface and the effect on the dynamic performance is investigated. By changing the amount of backlash of the gear tooth from 0 mm to 1 mm by 0.2 mm increment, the gear is modelled and analysed for three loading cases using MSC ADAMS software. This paper discusses the effect of backlash or uniformly worn out spur gear tooth faces on the dynamics specifically the contact and angular accelerations of the gear.publishedVersio

    Contact temperature analysis of the classical Geneva mechanism through numerical methods

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    In this study, the flash temperature of the classical Geneva mechanism has been studied using the numer- ical method. An excessive sliding motion between the wheel and pin leads to the generation of heat at the contact surfaces, which raises the surface temperature of the two contacting bodies. The flash tempera- ture has been anticipated for different loading cases and coefficients of friction. The analytical Blok equa- tion results are compared with the finite element results, and the results are satisfactory for maximum temperature. Based on the simulation results, the maximum contact temperature occurred in the driving crankpin within 10-15° and 70–75° of the angular position, and as the load increased the contact temper- ature also increases. In addition, the angular velocity increment produced higher temperatures than the torque load increments.publishedVersio

    Mechanical property characterization of water hyacinth and glass fiber reinforced hybrid composite

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    While composites of natural fibers have got more attraction because of their advantages, there are some limitations. Therefore, hybridization is a way to minimize some of the limitations of natural fibers composite. This article reports on the study conducted to investigate the mechanical properties of a hybrid glass/water hyacinth reinforced polymer composite using five different forms of volume fractions. The hybrid composite was prepared by hand lay-up method according to ASTM D3410 and ASTM D3039 standards for compression and tensile tests, respectively. The material properties of the composite were analyzed to explore the influence of fiber volume fraction. The results indicate that the mechanical properties change as a function of the volume fraction. Thus, the addition of glass fibers influenced the results of both tensile and compressive properties.publishedVersio

    Addressing Health Disparities Among Homeless in Alachua County through Community-Based Participatory Research.

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    Introduction. In states such as Florida that did not expand Medicaid, a large number of economically disadvantaged individuals do not qualify for subsidies to buy health insurance through the Affordable Care Act (ACA) 2. This leaves the health needs of Florida’s homeless population largely unaddressed. Nearly 48.1% of Alachua County’s homeless population has disabling conditions 16. This confirms a pressing need to understand the homeless population\u27s healthcare needs, knowledge, and barriers in accessing healthcare. Methods. We used a Community-Based Participatory Research model in conducting health fairs and needs assessment surveys, incentivizing participation, and providing education about existing resources. The surveys were conducted at two homeless meal service sites and consisted of 22 questions regarding access to healthcare, utilization, and satisfaction. Health fairs consisted of blood pressure, blood glucose, and mental health screening. Patient participation was encouraged through games, prizes and food. Results. Of the population we surveyed, 100% have income levels below $11,490, therefore all uninsured fall into the ACA coverage gap. Those less than 65 years of age do not qualify for Medicare unless disabled. Some qualify for Medicaid as shown in tables. Fifty-eight percent were uninsured and did not get any treatment for their illnesses. Additionally, 67% had no knowledge of free local healthcare clinics. Discussion/Conclusion. The majority of this population falls into the ACA Coverage Gap, lacks knowledge about free community clinics, and inappropriately uses the ED. Future implications of this research involve advocacy to expand Medicaid in Florida and enroll those who are eligible for health insurance. Vital goals include outreach by free healthcare clinics to make healthcare more accessible, as well as building trust with the community through continued outreach initiatives. A community-Based Participatory Research Model is an effective tool to increasing collaboration among diverse members of the community in order to bring meaningful and positive change to the health of populations

    Assessing the efficiency of sweet potato producers in the southern region of Ethiopia

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    Article purchased; Published online: 27 June 2017Applying stochastic frontier Cobb–Douglas production function, the study assessed the efficiency of sweet potato (Ipomoea batatas) producers in the Southern region of Ethiopia. The study revealed the existence of fairly large technical inefficiency in sweet potato production. The technical efficiency ranged from 12.6 to 93.7%, with more than half of the producers above the mean efficiency level (66.1%). This suggests that there is room for output gains through technical efficiency improvement. If the average producers in the study region are to achieve the technical efficiency level of the most efficient producer in the sample (93.7%), they can realize nearly 30% output gains. The analysis of allocative efficiency also revealed that sweet potato producers were producing sweet potato with sub-optimal utilization of production inputs, suggesting that potential for output gains remains to be exploited through reconfiguration of the existing resource use. They can make more value out of their sweet potato production by reconfiguring their current utilization of production inputs in favour of more land and manure but less seed rate. Furthermore, age and education are important determinants of the efficiency of sweet potato production. In view of these findings, it is advisable to put in place appropriate extension intervention programmes that enable sweet potato producers to exploit the potential gains in sweet potato output through technical and allocative efficiency improvement

    Internal Corrosion Damage Mechanisms of the Underground Water Pipelines

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    Internal water pipe corrosion is a complicated problem due to the interaction of water quality parameters with pipe wall. This study presents investigations of internal pipe surface corrosion mechanisms related to water physicochemical. Samples of water and corrosion-damaged ductile cast iron (30+ years) and galvanized steel pipe (15-20 years) were collected at in-situ condition from Addis Ababa city water distribution system. Scanning electron microscopy and optical microscopy were used to examine the pipes' corrosion morphology and microstructures, respectively. Additionally, Mountains 9 surface analysis software was used for further pitting corrosion characterization.To identify the causes of internal pipe corrosion, water physicochemical analyses were conducted by using inoLab pH 7310P, DR 900, Palintest Photometer 7100, and Miero 800. Water physicochemical test indicates: CaCO3 is 77 - 215 ppm, pH is 7.05 – 7.86, total dissolved solids (TDS) is 84.10 -262.8 ppm, ClO2 is 0 – 0.5 ppm, and dissolved oxygen (80-81 ppb). From water test results, major causes of internal pipe corrosion damage mechanisms were identified as dissolved oxygen, CaCO3, TDS, ClO2,and resistivity of water which initiates a differential cell that accelerates pipe corrosion. Using Mountain 9 surface analysis software, corrosion morphology and pitting features were characterized. The outputs of this paper will be helpful for water distribution and buried infrastructure owners to investigate corrosion damage mechanisms at early stage. To manage corrosion mechanisms, water supply owners need to conduct frequent inspections, recording of pipe data, testing of water quality, periodic pipelines washing, and apply preventative maintenance.publishedVersio

    Improving seed potato quality in Ethiopia: a value chain perspective

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    In Ethiopia, use of low-quality seed potatoes by the majority of potato growers is associated with underdevelopment of the seed potato value chains. Three seed potato systems are present in Ethiopia: the informal seed system, the alternative seed system and the formal seed system. This chapter analyses the performance of seed potato value chains with respect to their ability to supply quality seed tubers to seed potato systems, by using the chain performance drivers enabling environment, technology, market structure, chain coordination, farm management, and inputs. Information obtained from literature review, secondary data and key informants’ interviews were used for the analysis. In the informal seed system, seed potato value chains suffered from a poor enabling environment such as a low quality technical support and lack of a seed quality control system; use of sub-optimal storage and transportation technologies, sub-optimal farm management practices; and little use of inputs. In the alternative seed system, main constraints were the lack of a seed potato quality control system, poor farm management practices, little use of inputs by seed potato growers, and a distorted seed potato market that resulted from involvement of institutional buyers. Chains in the formal seed potato system were characterised by little involvement of the private and public sectors in the production and supply of seed potatoes. Based on the analysis, improvement options for the three seed systems were identified

    A global streamflow reanalysis for 1980–2018

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    Global and continental scale hydrological reanalysis datasets receive growing attention due to their increasing number of applications, ranging from water resources management, climate change studies, water related hazards and policy support. Until recently, their use was mostly limited to qualitative assessments, due to their coarse spatial and temporal resolution, large uncertainty and bias in the model output, and limited extent of the dataset in space and time. This research reports on the setup of a gridded hydrological model with quasi-global coverage, able to reproduce a seamless 39-year streamflow simulation in all world’s medium to large river basins. The model was calibrated at 1226 river sections with a total drainage area of 51 million km2 within 66 countries, using ECMWF’s latest atmospheric reanalysis ERA5. A performance assessment revealed large improvements in reproducing past discharge observations, in comparison to the calibration used in the current operational setup of the hydrological model as part of the Copernicus – Global Flood Awareness System (GloFAS, www.globalfloods.eu), with median scores of Kling-Gupta Efficiency KGE = 0.67 and correlation r = 0.8. The simulation bias was also dramatically reduced and narrowed around zero, with more than 60% of stations showing percent bias within ±20%. Pronounced regional differences in the simulation results remain, pointing out the need for detailed investigation of the hydrological processes in specific regions, including parts of Africa and South Asia. In addition, observed discharges with high data quality is key to achieving skillful model output. The new calibrated model will become part of the operational runs of GloFAS in the next system release foreseen for Spring 2020, together with a near real time extension of the streamflow reanalysis
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