Adama University

About: Adama University is a education organization based out in Nazrēt, Ethiopia. It is known for research contribution in the topics: Population & Adsorption. The organization has 840 authors who have published 1010 publications receiving 5547 citations. The organization is also known as: Adama Science and Technology University & ቴክኖሎጂ ዩኒቨርሲቲ, አዳማ ሳይንስና ቴክኖሎጂ ዩኒቨርሲቲ.

Effect of Mentoring on Military Personnel Retention

Abstract: Retention of human capital is an asset to any organization and as a result, mentoring and retention has become an issue of importance for any organization. This study, therefore, analyzed the effect of mentoring on military personnel retention in Ethiopian military academies. Methodologically, the research approach is quantitative and the design was descriptive and explanatory type of research, where the population of the study is the protégés of military academies in Ethiopia. The sampling method is probability and specifically stratified random sampling. The data were collected using structured questionnaires. The researcher used both descriptive and inferential statistics. The result of person correlation revealed that mentoring has positive and significant relationship with personnel retention in military academies. Furthermore, the results of regression analysis indicated that mentoring has positive and significant effect on personnel retention in the studied academies. It was found that psychological mentoring has higher effect on military personnel retention than career mentoring and role modeling. Findings of this study shows that providing mentoring for military personnel is positively and significantly related to higher psychological readiness, career development, and personnel retention. Military academies are better to emphasize on psychological mentoring to enhance the retention of military personnel.

Molecular and dissociative adsorption of CO and SO on the surface of Ir(111)

Abstract: This study investigates the molecular and dissociative adsorption of CO and SO molecules on the perfect and a defective Ir(111) surface. It is aimed at providing a broad spectrum of adsorption sites in terms of coordination of Ir atoms and investigating the role of surface defects on the adsorption of small molecules on the surface Ir(111). First-principles density functional theory (DFT) simulation with the generalized gradient approximation as it is implemented in Vienna ab initio simulation package has been employed for this study. Preferred adsorption sites, adsorption energies, and surface electronic structures of CO and SO molecules on the perfect and defective Ir(111) surfaces were calculated to obtain a systematic understanding on the nature of adsorption and dissociative interactions. The DFT calculation reveals the possible molecular adsorption of CO on both perfect and defective Ir(111) surface by the end-on manner (CO bond perpendicular to the surface); the later surface is found to be energetically more favorable. However, no dissociative adsorption was obtained. For SO molecule, on the other hand, both molecular and dissociative adsorption was observed. The defective surface is now less favorable in terms of adsorption energy, but yields stronger activation of SO. The nudged elastic band method investigation also reveals that the Pt single-atom catalysis significantly reduces (up to 80% reduction) the energy barrier of the dissociative adsorption of SO. The electronic structure calculation reveals that all the adsorptions investigated in this study involve hybridization of different electronic states.

ANFIS Modeling of Dynamic Load Balancing in LTE

Abstract: Modelling of ill-defined or unpredictable systems can be very challenging. Most models have relied on conventional mathematical models which does not adequately track some of the multifaceted challenges of such a system. Load balancing, which is a self-optimization operation of Self-Organizing Networks (SON), aims at ensuring an equitable distribution of users in the network. This translates into better user satisfaction and a more efficient use of network resources. Several methods for load balancing have been proposed. While some of them have a very buoyant theoretical basis, they are not practical. Furthermore, most of the techniques proposed the use of an iterative algorithm, which in itself is not computationally efficient as it does not take the unpredictable fluctuation of network load into consideration. This chapter proposes the use of soft computing, precisely Adaptive Neuro-Fuzzy Inference System (ANFIS) model, for dynamic QoS aware load balancing in 3GPP LTE. The use of ANFIS offers learning capability of neural network and knowledge representation of fuzzy logic for a load balancing solution that is cost effective and closer to human intuition. Three key load parameters (number of satisfied user in the net- work, virtual load of the serving eNodeB, and the overall state of the target eNodeB) are used to adjust the hysteresis value for load balancing.

Optimization of the Forming Parameters in U-Bending for Punch Force and Springback Using Taguchi Method

Abstract: Springback is a crucial factor that influences the feature of sheet metal in the sheet metal forming (SMF). In SMF operations, springback of the component during unloading mostly determines whether the component confirms to the design dimensions and tolerances. The aim of the current work is to analyze the importance of forming parameters on the responses: punch force and springback in U-Bending of SS 304. Strip length, punch speed and lubricant with three levels each have been considered in the current work as the forming parameters. The effects of different process parameters on U-bending of sheet metal have been investigated by conducting experiments on SS 304. Experiments have been conducted as per Taguchi’s L9 orthogonal array. The optimum conditions have been determined based on their effect on punch force and springback of the sheet metal.

Chemical Constituents of the Roots Extract of Dryopteris schimperiana and Evaluation for Antibacterial and Radical Scavenging Activities

Abstract: Dryopteris schimperiana (Dryopteridaceae) is traditionally used in folk medicine of Ethiopia against bacteria and internal parasites. In view of its traditional use and absence of scientific reports, an attempt was made to explore the chemical constituents, antibacterial and radical scavenging activities of the solvent extracts of the root of Dryopteris schimperiana. In this regard, the root was successively extracted with n-hexane, CHCl3 and methanol to afford 5 g (2%), 2 g (0.8%) and 26.6 g (10.6%), respectively. The n-hexane and CHCl3 extracts showing similar TLC profile were mixed and fractionated over silica gel column chromatography which led to the isolation of two compounds identified as heptacosanol (1) and isorhmentin (2). The structures of the isolated compounds were accomplished using spectroscopic methods including UV-Vis, IR and NMR. To the best of our knowledge, these compounds have not been reported from the genus Dryopteries. The extracts and isolated compounds were evaluated for their antibacterial activities using agar well diffusion method against two Gram-positive bacteria (Staphylococcus aureus and Bacillus subtitis) and two Gram-negative bacteria (E. coli and Salmonella). The results showed that the n-hexane extract, methanol extracts and isolated compounds were active against all tested bacteria, with compound 2 shown to have an inhibition zone of 17 mm which is comparable with the positive control. Furthermore the extracts and isolated compounds were assessed for their radical scavenging activity using DPPH assay. Isorhmentin (2) displayed pronounceable % radical scavenging activity (82.8%) compared with ascorbic acid indicating its strong ability to act as radical scavenger. This study demonstrated that the antibacterial and radical scavenging activity of the root of D. shimperiana is accounted to the presence of isorhamnetin. Therefore, the biological activity displayed by the constituents of the roots of D. shimperiana corroborates the traditional use of this plant against bacteria.Key words: Dryopteris schimperiana, NMR, antibacterial activity, antioxidant