https://dpublication.com/journal/EJEST/issue/feed European Journal of Engineering Science and Technology 2022-06-29T08:58:23+00:00 If you have any questions, please feel free to contact us: info@dpublication.com Open Journal Systems <p>European Journal of Engineering Science and Technology (EJEST) is a peer-reviewed, open-access journal that provides rapid publication of articles in all areas of Engineering Science and Technology. EJEST is an international, scholarly and peer-reviewed journal (online) published Quarterly by Diamond Scientific Publication.</p> https://dpublication.com/journal/EJEST/article/view/598 Towards Developing Criteria to Evaluate the Functional Performance Efficiency of Learning Spaces 2022-01-10T06:40:50+00:00 Sara Hisham Br sarahhisham1@yahoo.com Shahira Sharafeldin shira111@yahoo.com Sherif Sheta example@gmail.com Wesam Mehanna example@gmail.com <p>The spatial and geometric design of learning spaces plays an important role in transmitting the dynamics of learning. Recently, there has been a major milestone in effective teaching and learning methods (modern pedagogical approaches) that aim to shift students away from the traditional learning process towards collaborative, problem-oriented and independent learning. These changes required a new generation of learning spaces with different strategies and methods to adapt to these changes. This research problem lies in the huge gap between modern pedagogical methods and the spatial and geometric configuration of different learning spaces that do not meet the requirements of these methods. This article examines the impact of designing different learning spaces on learner-centred teaching and learning by understanding the interrelationships between research in architecture, learning sciences, and environmental psychology in order to achieve effective learning. As a result of the research, a set of criteria for evaluating the functional effectiveness of the research areas under consideration was developed.</p> 2021-12-20T00:00:00+00:00 Copyright (c) 2022 European Journal of Engineering Science and Technology https://dpublication.com/journal/EJEST/article/view/740 Performance comparison of classifiers on twitter sentimental analysis 2022-06-20T08:48:57+00:00 Shruti Wadhwa unknown@email.com Karuna Babber karunababber.kb@gmail.com <p>Twitter sentimental analysis is the way to examine polarity in tweeted opinions. The computational process involves implementing machine learning classifiers to categorize the tweets into positive, negative and neutral sentiments. To identify a suitable classifier for the task is a prime issue. In this paper we have presented the performance comparison of base classification techniques like Decision Tree, Random Forest, Naive Bayes, K-Nearest Neighbour and Logistic Regression on analysis of tweets. The results thus obtained show Logistic Regression analyze tweets with highest accuracy rate of 86.51% and the least performer comes out to be K-Nearest Neighbour with an average accuracy rate of 50.40%.</p> 2021-12-20T00:00:00+00:00 Copyright (c) 2022 European Journal of Engineering Science and Technology https://dpublication.com/journal/EJEST/article/view/739 Techno Economy Comparison of Conventional Generating Unit and Lithium Battery Energy Storage as a Primary Frequency Regulation of Variable Renewable Energy Penetrated Grid System, Case Study: Southern Sulawesi of Indonesia 2022-06-20T07:35:13+00:00 Rendy Yuliansyah rendyye@gmail.com Aditya Idamsyah unknown@email.com Irwan Paundra unknown@email.com Bambang Priyono unknown@email.com <p>Integrating higher shares energy mix of variable renewable energy (VRE) technologies, such as wind and solar PV, in the energy transition process presents many challenges in its operation. One of the required services needed in this activity is the Primary Frequency Regulation (PFR). Many studies have studied various ways to provide PFR services, such as using the Conventional Generating Unit (CGU) and Lithium Battery Energy Storage (LiBESS). This paper presents several battery sizing methods used for comparison between the Levelized Cost of Electricity (LCOE) of a CGU and the Levelized Cost of Storage (LCOS) of a LiBESS, which used as PFR of a VRE penetrated grid system in a case study: the grid of southern Sulawesi, Indonesia. The results show that the LCOE of LiBESS is still below the LCOE of the CGU, but for projections in 2030, the LCOS LiBESS shows a competitive number compared to the LCOE of CGU.</p> 2021-12-20T00:00:00+00:00 Copyright (c) 2022 European Journal of Engineering Science and Technology https://dpublication.com/journal/EJEST/article/view/607 Integrated Modeling of Natural Tin Photoactivation 2022-01-10T06:53:48+00:00 Cristiana Oprea coprea2007@yahoo.co.uk Alexandru Mihul unknown@email.com Alexandru Ioan Oprea unknown@email.com <p>In this study photoactivation reaction cross-sections on natural Sn were evaluated in the GDR region for incident neutron energy up to some ten’s of MeV’s. For each Sn isotope, the contribution of the compound, direct and preequilibrium mechanisms were extracted. The cross-sections and isomer ratios were calculated. The results are compared with existing experimental data obtained by Bremsstrahlung source and activation methods.</p> <p>Theoretical evaluations of the photoactivation cross-sections obtained with Talys are in good agreement with existing experimental data. Taking into account the satisfactory description of experimental cross-section data, the isomer ratios for incident photons energy from the neutron threshold (8¸9 MeV) up to 36 MeV were calculated.</p> <p>If the isomer nuclei are obtained in final states then the isomer ratios were evaluated using the corresponding production cross-sections (s<sub>m</sub>, s<sub>g</sub>) in the exclusive (g, 1n) reactions. In the present work, the results of (g, n) reaction on <sup>114</sup>Sn and <sup>120</sup>Sn nuclei are analyzed.</p> 2021-12-20T00:00:00+00:00 Copyright (c) 2022 European Journal of Engineering Science and Technology