Adama Science and Technology University

www.astu.edu.et
Nazret, Ethiopia
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Lee H.-G.,Adama Science and Technology University | Lee H.-G.,Pohang University of Science and Technology
ISIJ International | Year: 2017

The Graduate Institute of Ferrous Technology (GIFT) under the umbrella of Pohang University of Science and Technology (POSTECH) in Korea was established in 2005, aiming at education and research in all that is steel. It is currently run with three centers which have eleven laboratories in all, each of which focuses on a particular aspect of ferrous technology. GIFT offers both master's and PhD programs, both specialized in ferrous technology. It covers process, product and application of steels and steel-related materials. It also keeps developing close links with steel producers, users and supporters. The interaction happens via many mechanisms including collaborative projects, workshops, participation in teaching, employment of highly trained graduates, secondments from industry to conduct research at GIFT, etc. Such interactions are considered vital in the two-way transfer of knowledge, ideas and direction. In this report, the educational performance of GIFT is briefly summarized. The research emphasis of each center and focal research areas of each laboratory are also outlined. An example out of recent research outcomes of GIFT, which is about a novel approach to the development of light-weight steels, is elaborated in some detail. © 2017 ISIJ.


Jain S.,Adama Science and Technology University
Neues Jahrbuch fur Geologie und Palaontologie - Abhandlungen | Year: 2017

New data on two rare genera (Phlycticeras and Pachyerymnoceras) from the Callovian (Middle Jurassic) sediments of Kachchh, western India are presented with an update on their South Tethyan occurrences. This paper documents the earliest occurrence of the genus Phlycticeras from the entire south of Tethys (P. polygonium var. polygonium [M]) from latest Early Callovian sediments (= Proximum Subzone, Gracilis Zone). Further, in light of the new taxonomic data, the previously recorded early Middle Callovian P. gr. pustulatum [M] is reevaluated as also all other Phlycticeras occurrences from the Indian subcontinent. Data suggests that in Kachchh, Phlycticeras has a long range from the latest Early to Late Callovian interval. Additionally, two new macroconch species of Pachyerymnoceras are also described and illustrated from Late Callovian sediments. A critical review of previous records suggests that in Kachchh, Pachyerymnoceras is restricted to the Submediterranean interval of the Collotiformis-Poculum subzones of the Athleta Zone. A note on the paleobiogeography and probable migratory routes of these two genera to India and elsewhere is also suggested. © 2017 E.


Kim M.,Pohang University of Science and Technology | Heo J.,Pohang University of Science and Technology | Heo J.,Adama Science and Technology University
Ceramics International | Year: 2015

Glass-ceramic wasteforms containing vitusite (Na3Ce(PO4)2) and Ce-rich crystals were investigated to immobilize lanthanide oxide wastes generated by pyro-processing. Controlled crystallization of alkali borosilicate glasses containing small amounts of P2O5 by heating at T>600 °C for 3 h resulted in formation of vitusite as a major crystalline phase with a minor Ce-rich crystalline phase. Lanthanide oxide waste loading was 11.87 wt%. Rare-earth wastes were efficiently immobilized inside the crystalline phases: lanthanide elements such as Ce and Nd constituted ∼26 wt% of vitusite and 80 wt% of Ce-rich crystals. Amounts of Ce and Nd ions released in a product consistency test were below the detection limit (0.1 ppm) of inductively coupled plasma atomic emission spectroscopy. Glass-ceramic wasteforms that contain vitusite crystals are good candidates to immobilize lanthanide wastes generated by pyro-processing. © 2015 Elsevier Ltd and Techna Group S.r.l.


Anandakumar P.,Adama Science and Technology University | Kamaraj S.,University of Madras | Jagan S.,University of Madras | Ramakrishnan G.,University of Madras | Devaki T.,University of Madras
International Immunopharmacology | Year: 2013

Capsaicin (CAP), a constituent of red chilli and red pepper is exposed to exert compelling anticarcinogenic effects. In the present study, we examined the anti-tumorigenic potential of CAP on benzo(a)pyrene-induced mice lung tumorigenesis by analyzing the markers of apoptosis. Intraperitoneal administration of CAP (10 mg/kg body weight) to Swiss albino mice suppressed the development of lung carcinoma by amending the protein expressions of apoptotic regulators p53, Bcl-2, Bax and caspase-3. The apoptotic-inducing nature of CAP was further confirmed by DNA agarose gel electrophoresis, transmission electron microscopic study and ethidium bromide/acridine orange staining. The results obtained from the present study show that CAP inhibits the development of mice lung carcinogenesis through its ability to induce apoptosis. Our present findings provide the basis for further clinical exploration of CAP as an anti-carcinogenic compound against lung carcinogenesis. © 2013 Elsevier B.V. All rights reserved.


Mihret Z.,Adama Science and Technology University | Ahmad M.W.,Adama Science and Technology University
Procedia Computer Science | Year: 2016

The field of Cryptography has developed by numerous incidents of proposed new Algorithms, their verification and their subsequent cryptanalysis. This paper provides a novel approach to verify the structural and functional correctness of a cryptographic algorithm with implicit recovery of the model into an extended finite state machine. The proposed method is used to analyze one particular algorithm proposed in the past with the name Reverse Encryption Algorithm (REA). On critical analysis based on Shannon's principle of confusion and diffusion, The REA algorithm fails to qualify as a symmetric key encryption algorithm. The decryption algorithm is simply found to be a non-key reverse transformation of Ciphertext and therefore the performance of REA algorithm cannot be compared with the DES or any other well proven algorithm used in the cryptography. The reported performance comparison also seems to be meaningless as the most of the time of REA algorithm is wasted in performing the ASCII, BINARY and REVRSE operations while there is no application of confusion and diffusion logic, which makes it vulnerable for primitive Cryptanalysis. The purpose of the paper is to develop a framework for verification of correctness of the encryption and decryption algorithms, and apply the framework to prove the structural and functional validly of the REA algorithm as a case study. © 2016 The Authors. Published by Elsevier B.V.


Gebreselassie T.R.,Adama Science and Technology University
Agricultural Engineering International: CIGR Journal | Year: 2014

Dekoko is a cool season legume plant grown in northern Africa. It is a rich source of protein for people in the region. The effect of moisture on some of the physical properties of dekoko seed was studied because it frequently affects some important parameters for the design of mechanical unit operations. The moisture content of dekoko seed was determined according to ASAE standards S352.3 and all other physical properties following standard procedure described elsewhere. The length, width, thickness, geometric mean diameter, thousand seed mass, porosity, true density and angle of repose increased from 5.60 to 6.51 mm, 4.99 to 5.78 mm, 4.60 to 5.44 mm, 5.05 to 5.89 mm, 94.08 to 126.10 g, 39.36 to 48.14%, 1361.66 to 1470.77 kg/m3 and 29.89° to 37.84° respectively. The sphericity increased from 90.05% to 91.14% with increase in moisture content from 10.28% to 19.67% and decreased from 90.83% to 90.55% with further increase of moisture content from 24.42% to 28.61%. Whereas, bulk density decreased from 829.89 kg/m3 at 10.28% to 762.75 kg/m3 at 28.61% moisture content. In the same moisture range, the lowest value of static coefficient of friction recorded when dekoko seed slide against mild steel (0.35 to 0.48,) and the highest value of static coefficient of friction noticed when dekoko seed slide against plywood (0.42 to 0.54). The static coefficient of friction of for galvanized iron increased from (0.37 to 0.51) as moisture increased from 10.28% to 28.61%. Generally, moisture content directly or indirectly affected the physical properties of dekoko seeds.


Borojo D.G.,Adama Science and Technology University
International Journal of Energy Economics and Policy | Year: 2015

This study has applied a recursive dynamic computable general equilibrium model to examine the economic impact of investment on infrastructure for electricity using an updated 2009/10 social accounting matrix. Three simulations (foreign saving, domestic household and enterprises saving and mix of foreign and domestic saving to finance the investment) in combination with total factor productivity of industrial and service sectors are used. The findings of the study have shown the improvement of the real gross domestic product (GDP), output of industrial and service sectors in all simulations. Nonetheless, mixed effects have found on household consumption and trade balance. The highest growth of real GDP is registered when the investment on electricity is fully financed by domestic household and enterprise saving. However, household consumption expenditure has grown at negative rate worsening the welfare of households. Investment on electricity fully financed by foreign saving is resulted in lower growth rate of real GDP due to worsening of net export. In addition, it has benefits for households as it increases their welfare. But it is to be repaid in the future that would increase indebtedness of the country. So, financing the investment partly by domestic household saving and foreign saving would be worthwhile. © 2015, Econjournals. All rights reserved.


Gebreselassie T.R.,Adama Science and Technology University
Agricultural Engineering International: CIGR Journal | Year: 2012

Design of unit operations for mechanical and pneumatic cleaning, transportation (conveying), processing and storage of cardamom seeds are dependent on moisture content. Some of moisture dependent physical properties of cardamom seeds were studied at moisture contents 9.9%, 13.57%, 18.41%, and 23.29% wet basis (w.b.). The length, width, thickness, geometric mean diameter, thousand seed mass, and sphericity increased from 17.01 to 17.30 mm, 5.68 to 6.57 mm, 5.02 to 5.35 mm, 7.86 to 8.47 mm, 120.83 to 165.60 g, and 0.46 to 0.49, respectively, with the increase in the moisture content from 9.9 to 23.29% w.b. As the moisture content increased from 9.9 to 23.29% the bulk density, true density, and porosity decreased from 408.2 to 358.90 kg/m 3, 926.57 to787.19 kg/m 3, and 55.94 to 54.41%, respectively. The angle of repose increased from 72.16° at 9.9% to 73.80° at 23.29% moisture content. Whereas, the static coefficient of friction increased with the increase in moisture content from 9.9 to 23.29% on three different surfaces. The highest static coefficient of friction was recorded when cardamom seed against plywood (0.47 to 0.56), and lowest static coefficient of friction against mild steel (0.41 to 0.50). The static coefficient of friction between cardamom seeds and galvanized iron surface increased from 0.44 to 0.53 within the studied moisture content range.


Ashango A.A.,Adama Science and Technology University | Patra N.R.,Indian Institute of Technology Kanpur
Journal of Materials in Civil Engineering | Year: 2016

This paper presents the stabilization of expansive soil (C) with steel slag (SS), rice husk ash (RHA), and quick lime (L). The geotechnical properties, shearing strength characteristics, and dynamic properties of stabilized soil have been studied. The optimum mix is found to be in the proportion of 65C + 20SS + 5L + 10RHA. The unconfined compressive test shows that strength of treated soil increases about 45 and 90% for uncured and cured samples at 30 days. The soaked California bearing ratio (CBR) test shows that the strength increases with increasing curing periods from 7 to 30 days. Laboratory strain-controlled cyclic triaxial tests have been carried out under undrained conditions to study the dynamic properties of stabilized soil for different strain amplitudes and frequencies. The stiffness of stabilized soil increases to 58-78% as compared to clay soil. This study discussed the suitability of stabilized material for subgrade pavement. © 2016 American Society of Civil Engineers.


Getachew M.,Adama Science and Technology University | Yewhalaw D.,Jimma University | Tafess K.,Adama Science and Technology University | Getachew Y.,Jimma University | Zeynudin A.,Jimma University
Parasites and Vectors | Year: 2012

Background: Anaemia is known to be one of the outcomes of parasitic infection and it may result in impaired cognitive development, reduced physical work capacity and in severe cases increased risk of mortality, particularly during the prenatal period. The aim of this study was to determine the prevalence and associated risk factors of anaemia among pregnant women in Gilgel-Gibe dam area, southwestern Ethiopia. Methods. A cross-sectional community based study was conducted on 388 pregnant women living in three districts around Gilgel Gibe Dam area, southwestern Ethiopia. Socio-demographic and socio-economic data were collected from each participant. A single stool sample was also collected from each selected pregnant woman. Haemoglobin concentration was determined by the cyanmethemoglobin method. Plasmodium infection prevalence and intensity were assessed with thin and thick blood film examination. Results: Of the total 388 study participants, 209 (53.9%) were anaemic. Pregnant woman who were rural residents (Adjusted odds ratio (AOR) = 1.62, 95% C.I: 1.02-2.62, P= 0.042), not using insecticide treated nets (ITNs) during the study period (AOR = 2.84, 95% C.I: 1.33-6.05, p = 0.007), those who were Plasmodium malaria infected (AOR = 11.19, 95% C.I: 3.31-37.7, p= 0.01) and those with Soil Transmitted Helminth (STH) infections (AOR=1.82, 95% C.I: 1.16-2.87, p=0.001) had higher odds of being anaemic than those who were urban residents, using ITNs, free of Plasmodium malaria and Soil transmitted helminth infection, respectively. There was a significant correlation between increasing hookworm parasite load (r = -.110, P< 0.001), Ascaris lumbricoides (r = -.122, P < 0.001) and Trichuris trichiura (r = -.025, P < 0.001) and decreasing hematocrit values. Conclusion: The high prevalence of anaemia indicates it is currently a serious health problem of pregnant women living in Gilgel Gibe Dam area. Plasmodium malaria and soil transmitted helminth infections were significantly associated with anaemia. Antenatal care should promote de-worming and education on personal hygiene. Therefore, there is a need to design strategies that help to diagnose pregnant women for malaria and STH infections during their antenatal care (ANC) visit instead of testing for only haemoglobin (Hgb) levels and blood group. © 2012 Getachew et al.; licensee BioMed Central Ltd.

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