Papers by Dr.Solomon Tesfamariam
Reliability Engineering & System Safety, 2021
DOI to the publisher's website. • The final author version and the galley proof are versions of t... more DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal. If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the "Taverne" license above, please follow below link for the End User Agreement:
International Journal of Disaster Risk Reduction, 2018
21 22 Residential buildings are designed to withstand earthquake damage because it causes the bui... more 21 22 Residential buildings are designed to withstand earthquake damage because it causes the buildings to be inhabitable for a 23 period of time, called the downtime. This paper introduces a method to predict the downtime of buildings using a Fuzzy 24 logic hierarchical scheme. Downtime is divided into three components: downtime due to the actual damage (DT1); 25 downtime due to irrational delays (DT2); and downtime due to utilities disruption (DT3). DT1 is evaluated by relating 26 the damageability of the building's components to pre-defined repair times. A rapid visual screening is proposed to 27 acquire information about the analyzed building. This information is used through a hierarchical scheme to evaluate the 28 building vulnerability, which is combined with a given earthquake intensity to obtain the building damageability. DT2 29 and DT3 are estimated using the REDi TM Guidelines. DT2 considers irrational components through a specific sequence, 30 which defines the order of components repair, while DT3 depends on the site seismic hazard and on the infrastructure 31 vulnerability. The proposed method allows to estimate downtime combining the three components above, identifying 32 three recovery states: re-occupancy; functional recovery; and full recovery. A case study illustrating the applicability of 33 the methodology is provided in the paper. The downtime analysis is applied to buildings with low and medium damage 34 levels. Results from the case study show that total repair time is higher in the medium damage case, as it is expected. In 35 both evaluations, the downtime is influenced more by irrational components and it is different in the three recovery 36 states.
PLOS ONE
The demand for water-energy (WE) should be addressed with their sustainable supply in the long-te... more The demand for water-energy (WE) should be addressed with their sustainable supply in the long-term planning. The total energy demand was estimated to be around 14,000000 and 53,000000 MWh for 2030 and 2050 years respectively. These years’ predicted water demand was 0.4 and 0.7 billion-cubic-meter. Based on the estimated energy and water demand, sustainable supply through WE management were determined. In 2030 and 2050 the water supply-demand balance index is around 1, showed water demand will be met for respective years, whereas the energy supply-balance after the intervention become around 0.9 and 0.7. The study results clearly predicted future WE demand of Addis Ababa city and have been put their quantified supply suggestion.
Water Policy, 2022
This study aims to understand the long-term (2020–2050) urban water–energy–food (WEF) resources a... more This study aims to understand the long-term (2020–2050) urban water–energy–food (WEF) resources access and sustainability in Addis Ababa city through a nexus modeling approach. Several feasible scenarios in line with improving WEF resources supply and access through conservation, system rehabilitation and technology input are explored. The water system scenarios include rehabilitation and conservation scenario, water supply enhancement scenario, technology input scenario and integrated water improvement scenario. The energy scenario includes energy conservation scenario and new renewable supply enhancement scenarios and integration of both scenarios as integrated energy scenario. The food system scenarios include crop yield productivity and irrigation water use efficiency scenarios of urban agricultural system. The integrated WEF nexus scenario is the integration of all scenarios under one nexus framework. The results are evaluated against baseline scenario. At a system level, the i...
Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering, 2021
Water and energy are so versatile that play great role in fulfilling the daily requirements of hu... more Water and energy are so versatile that play great role in fulfilling the daily requirements of human life. Having knowledge on the future water and energy demand of the world, country, region and even a single city/town helps for planning and establishing water and energy policies. A regression model was used to estimate the energy and water demand considering the socioeconomic drivers as parameters. An average population growth rate of 5.2% and a GDP growth rate of 11% were used as base scenarios to predict the residential, commercial and industrial energy demands. Population and GDP per capita based scenario was used to predict the transport (street-lighting) energy demand. The total energy demand for residential, commercial, industrial sectors and street-lighting was around 50 and 190 Peta Joule in 2030 and 2050 respectively. Additional, the energy requirement for water distribution, transmission, and water treatment was determined. Similarly, this scenario was used to determine residential, commercial and industrial water demand. The total water demand was predicted to be 0.4 and 0.68 billion cubic meters in 2030 and 2050 respectively.
International Journal of Literature and Arts, Aug 23, 2014
A system to recover part of the energy of exhaust air from an axial fan of 75kW using a Horizonta... more A system to recover part of the energy of exhaust air from an axial fan of 75kW using a Horizontal Axis Wind Turbine is discussed in this paper. The actual air data at the fan outlet are collected from central air conditioning station of a composite textile mill (Kombolcha Textile Share Company) using log-Tchebycheff method. Since the air flow type determines the steps in progress the air flow type is arithmetically found to be fully turbulent. A duct is designed to correct the air turbulence and transport the exhaust air from the fan to the turbine. The enclosure duct design is developed in consideration of the actual situation of the company to attain a fully developed region where the air speed attains a uniform velocity profile and create a venturi effect (to increase the air speed) for better energy output and guide the air before it interacts with the wind turbine blades. By turning what was exhausted to useable form 5.7kW of electric power can be harvested. As there are vast application areas of industrial air system, utilizing the exhaust from such air systems as energy resource could be helpful and used as supplementary power for industry production floor lighting and little power supply requiring auxiliary processes.
Journal of Water and Climate Change, 2021
As part of sustainable urban planning, the demand for water and energy (WE) should also be addres... more As part of sustainable urban planning, the demand for water and energy (WE) should also be addressed. The Waikato Environment for Knowledge Analysis (WEKA) modeling tool was employed to relate the historical WE consumptions with the population and economic growth scenarios using a linear regression model. The performance of the model was evaluated to properly identify the most influential drivers in each sector. The WE demand prediction was made for each year from 2016 up to 2050. Consequently, the long-term time interval for demand analysis is important rather than the consequent year for planning. The total electric energy demand including residential, street-lighting, commercial and industrial sectors was estimated to be around 14,000 and 53,000 Giga Watt hour (GWh) for the years 2030 and 2050, respectively. These years' forecasted petroleum demand was around 8840 and 30,140 for diesel, 13,860 and 52,700 for gasoline, and 1230 and 9890 GWh for kerosene and the water demand in...
Applied Physics Research, 2018
This study assesses the impacts of climate change on water resources over Mbarali River sub-catch... more This study assesses the impacts of climate change on water resources over Mbarali River sub-catchment using high resolution climate simulations from the Coordinated Regional Climate Downscaling Experiment Regional Climate Models (CORDEX_RCMs). Daily rainfall, minimum and maximum temperatures for historical climate (1971-2000) and for the future climate projection (2011-2100) under two Representative Concentration Pathways RCP 8.5 and RCP 4.5 were used as input into the Soil and Water Assessment Tool (SWAT) hydrological model to simulate stream flows and water balance components for the Mbarali River sub-catchment. The impacts of climate change on hydrological conditions over Mbarali river catchment were assessed by comparing the mean values of stream flows and water balance components during the present (2011-2040), mid (2041-2070) and end (2071-2100) centuries with their respective mean values in the baseline (1971-2000) climate condition. The results of the study indicate that, in...
This workshop report forms a deliverable of WP1 of the '<em>Energy System Development P... more This workshop report forms a deliverable of WP1 of the '<em>Energy System Development Pathways for Ethiopia' </em>(Pathways) project led collaboratively between University College London (UCL), Policy Studies Institute of Ethiopia (PSI), the Royal Institute of Technology Stockholm (KTH) and Addis Ababa Institute of Technology (AAiT). The Pathways project aims to enhance modelling capabilities in Ethiopia to support the development of energy system development pathways for Ethiopia in a context of rapidly increasing demand for energy. It suggests qualitative storylines for future resource development and address knowledge gaps on how demand for electricity, including electricity for productive uses and demand side policies might affect energy system development pathways. In August 2019, this one-day event was held in Addis Ababa UCLPSI to discuss future energy pathways for Ethiopia. This formed the first stage of the Pathways project and had the objective of deriv...
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Papers by Dr.Solomon Tesfamariam