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Performance of Drip Irrigation at Werer, Middle Awash, Ethiopia
Fikadu Robi Borena,
Robi Borena
Issue:
Volume 6, Issue 4, December 2021
Pages:
57-61
Received:
26 July 2021
Accepted:
6 August 2021
Published:
19 October 2021
Abstract: Agriculture is the main contributor of the Ethiopian economy as it accounts for about 55% of the GDP, 60% of the foreign exchange earnings and provides livelihood to 85% of the population. The field experiments were conducted to evaluate the performance of drip irrigation systems werer agricultural research station, middle awash, Ethiopia. Middle awash is largest irrigated part of the country. It is well gifted with the land, sunshine and highly fortune in available water resources. Drip irrigation has greater water economy over other systems in arid and semi-arid regions characterized by high evaporation rates and it has the potential to increase yields of crops even with reduced irrigation water application. The performance of drip irrigation system was evaluated on the basis of parameters like emitter flow variation (qvar), distribution uniformity (DU), application uniformity (Ea), coefficient of variation (CV), statistical uniformity (SU) and Christiansen uniformity coefficient (UCC). High values of uniformity coefficient and uniformity of distribution are attributed to the effect land levelling. The hydraulic performance of drip irrigation result shows the emitter flow variation (0.07%), emission uniformity (92.2%), coefficient of variation (0.07%), Christiansen uniformity coefficient (90.8) and application efficiency of (85%).
Abstract: Agriculture is the main contributor of the Ethiopian economy as it accounts for about 55% of the GDP, 60% of the foreign exchange earnings and provides livelihood to 85% of the population. The field experiments were conducted to evaluate the performance of drip irrigation systems werer agricultural research station, middle awash, Ethiopia. Middle a...
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Analysing Organizational Development Tenets for Improving Performance of Local Contracting Firms in Tanzania: A Conceptual Model
Yazidi Hassan Bakari Mwishwa
Issue:
Volume 6, Issue 4, December 2021
Pages:
62-70
Received:
23 October 2021
Accepted:
29 November 2021
Published:
7 December 2021
Abstract: Construction industry in Tanzania is affected with poor project performance. The poor project performance of the industry is attributed to by three key players, clients, consultants and contractors who are been characterised by: inadequate planning, ad hoc process, weak adoption of IT in their processes, inadequate procurement and project delivery processes, weak capital and cash flow management skills, lack of innovation and entrepreneurship skills, lack of formal organizational structures and lack of work commitment culture. While these key project players record inadequate performance, facets of ‘organizational development’ are found to exist in literature for decades; but are not yet well evaluated with a view of marrying the local firms’ performance characteristics. This paper reviews and evaluates relevant literatures on the local contracting firms’ performance and on the organizational development models in general. Such reviewed works helped to formulate organizational development conceptual model for improving local firms’ performance. The model has eight dimensions: change initiatives, strategies of improvement, organizational wide elements, organizational-wide elements weaknesses, organizational wide efficiencies and effectiveness, interdisciplined deployment, emerged field issues and real change results. The model contributes in the body of knowledge through providing a comprehensive and yet rigorous list of organizational development elements with the procedural approach to help local firms to assess and improve own performance. Such a model benefits own local firms as well as others in the developing countries. The model opens avenues for further researches by creating a room to conduct model validation.
Abstract: Construction industry in Tanzania is affected with poor project performance. The poor project performance of the industry is attributed to by three key players, clients, consultants and contractors who are been characterised by: inadequate planning, ad hoc process, weak adoption of IT in their processes, inadequate procurement and project delivery ...
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Effect of Land Use/Cover and Dam on River Morphological Change in Este District, Gomit River, Amhara, Ethiopia
Abiyu Wubalem,
Dawit Yihunie
Issue:
Volume 6, Issue 4, December 2021
Pages:
71-81
Received:
19 November 2021
Accepted:
9 December 2021
Published:
24 December 2021
Abstract: Recently, the construction of dams has affected the morphological process of the downstream river reach by storing water and sediment, changing the water discharge regime of the river and releasing relatively clear water to the downstream. Due to this, GIS and RS software have been used to identify land use and land cover changes, as well as the dam impact of the downstream of the river. The objective of this research is to determine the effect of land use, land cover change, and dams on river morphological change in the Gomit River. The methodology of the study was used four significant parameters (land sat imaginary, slope, soil, and river cross-section) to determine the river morphological change of the study area. Land use/cover changes have been recognized as percent (%), which are forest and grass land, have been decreased by 3 and 27% respectively. Whereas the caltivation land and settlement area were become increasing 26 and 3.4% respectively, While the degrading and aggradation values have been obtained 0.612m, 0.566 and 0.345m from the respective years of 2002, 2016 and 2020 respectively. The sinuosity index values of the years were obtained (2002, 2016 and 2020) is 1.374, 1.30 and 1.294 respectively. As the result the narrowed and widened values are 79.99 and 20.01% respectively.
Abstract: Recently, the construction of dams has affected the morphological process of the downstream river reach by storing water and sediment, changing the water discharge regime of the river and releasing relatively clear water to the downstream. Due to this, GIS and RS software have been used to identify land use and land cover changes, as well as the da...
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Coal Mill Foundation – A Finite Element Approach for Study of Dynamic Analysis
Nulu Reddeppa,
Bommireddy Jayarami Reddy,
Hanchate Sudarsana Rao
Issue:
Volume 6, Issue 4, December 2021
Pages:
82-99
Received:
20 November 2021
Accepted:
14 December 2021
Published:
29 December 2021
Abstract: In general coal mill foundation consist of a block foundation with heavy concrete mass. Its dynamic behavior is studied using Barkan’s1 method by most of the engineering practitioners. Foundation is generally sized such that the foundation mass is about more than three times the mass of the equipment using the empirical guidelines. This method has limitations in providing wholistic details of foundation behavior like transient stage deformations and response for the exited forces, foundation response at specific areas/nodes of the foundation etc. Also, this method has got limitation in mode shapes. This method can provide only fundamental mode shapes. That is in three linear directions and three rotational directions. But in practical, Mode shapes exist with coupled directions with appropriate mass participations over and above the fundamental directions. In this study a three-dimensional Finite Element Model is used to study coal mill foundation dynamic response and it’s behavior. This approach plugs all the limitations of Barkan’s method. ANSYS software is used for modeling the foundation with three-dimensional Finite Elements. Appropriate soil structure interaction is resembled with suitable elements available in ANSYS element library. Dynamic forces from coal mill, gear box and motor which act at different frequencies and at different planes are applied on the model at appropriate nodes. Natural frequencies of the foundation system and displacement amplitudes from the forced vibration analysis are obtained using the above model. Mode shapes of the various modes are plotted. Foundation response for equipment startup and shut down conditions (transient stages) are studied by plotting displacement amplitudes w.r.t frequency variation.
Abstract: In general coal mill foundation consist of a block foundation with heavy concrete mass. Its dynamic behavior is studied using Barkan’s1 method by most of the engineering practitioners. Foundation is generally sized such that the foundation mass is about more than three times the mass of the equipment using the empirical guidelines. This method has ...
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