ICONTECH INTERNATIONAL JOURNAL https://icontechjournal.com/index.php/iij <p>ICONTECH INTERNATIONAL JOURNAL is open access, peer-reviewed, international indexed and refereed journal published by IEDSR ASSOCIATION. Its main objective is to provide an intellectual platform for the international scholars. It aims to promote scientific studies in science and technology and become the leading journal in the relevant field. </p> Icontech Scientific Studies Society en-US ICONTECH INTERNATIONAL JOURNAL 2717-7270 THE RELATIONSHIP BETWEEN TRANSACTIONAL LEADERSHIP AND KNOWLEDGE MANAGEMENT https://icontechjournal.com/index.php/iij/article/view/168 <p>Leaders do not have the same attitude or the same perspective. It seems that there are many types of leadership that can be exhibited by leaders in the political, commercial or other fields. Leadership style is the way a leader provides direction, implements plans, and motivates people. When we look at the transactional leadership style, it primarily involves motivating and directing followers by appealing to their own interests. In addition, knowledge management is the process of capturing, developing, sharing and effectively using organizational knowledge. It refers to a multidisciplinary approach to achieve organizational goals by making the best use of knowledge. It is known that the leadership style has a direct impact on the organization’s tendency and form to meet the processes and steps of knowledge management. This study aims to examine the relationship between the operational leadership characteristics of health personnel working in a public hospital to knowledge management. Descriptive statistics technique was used to analyse the variables and investigate the hypotheses.</p> Elif Maltaş Muhammet GÜMÜŞ Sibel ORHAN Emine KIZILKAYA Copyright (c) 2021 ICONTECH INTERNATIONAL JOURNAL https://creativecommons.org/licenses/by-nc-nd/4.0 2021-09-25 2021-09-25 5 3 1 6 10.46291/ICONTECHvol5iss3pp1-6 In vitro antioxidant properties of 2-(4-(2-hydroxybenzylideneamino)benzylideneamino)benzoic acid https://icontechjournal.com/index.php/iij/article/view/181 <p>In recent years, it has attracted great attention to determine and appraise synthetic antioxidants with high free radical scavenging capacity associated with various disorders. Because synthetic antioxidants are widely used in place of native antioxidants as they are influential and less expensive. In this study, the antioxidant activity of the newly synthesized asymmetric diimine Schiff base was determined by using DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging, ferrous ion chelation (FIC) activity and total antioxidant activity (Phosphomolybdenum assay) methods. The effective concentration (IC<sub>50</sub>) values were calculated for the Schiff base and standards. According to the results of DPPH radical scavenging, ferrous ion chelation and total antioxidant methods, Schiff base showed a well antioxidant activity. It was determined that Schiff base is reactive towards DPPH radicals (IC<sub>50</sub>, 180.0 μM) and especially Fe<sup>+2</sup> ions (IC<sub>50</sub>, 76.3 μM). It was also found that it actively reduces the Mo(VI) ion to the Mo(V) form (IC<sub>50</sub>, 121.5 μM). The our results indicate Schiff base, may be a fine candidate as a source of synthetic antioxidants and possibly strong drug.</p> Zehra Kübra YILMAZ Belma ASIM Ozlem OZDEMIR Copyright (c) 2021 ICONTECH INTERNATIONAL JOURNAL https://creativecommons.org/licenses/by-nc-nd/4.0 2021-09-25 2021-09-25 5 3 7 12 10.46291/ICONTECHvol5iss3pp7-12 Bioethanol Production Through Syngas Fermentation by a Novel Immobilized Bioreactor Using Clostridium Ragsdalei https://icontechjournal.com/index.php/iij/article/view/183 <p>Global energy demand has been escalating creating ever increasing pressure on climate crisis caused by fossil-based fuels. Humankind is now desperately in need of alternative and sustainable energy sources. Therefore, biofuels provide promising solution.</p> <p>Amongst the various biofuels, bioethanol from syngas, which is a mixture of, mostly, CO, CO<sub>2</sub>, N<sub>2</sub>, H<sub>2</sub>, and CH<sub>4</sub> gases has been drawing increasing attention recently. Regarding this, the conversion of syngas to bioethanol, an alternative biofuel to fossil fuels, is considered a promising approach to reduce the negative effects of global warming by reducing greenhouse gas emissions.</p> <p>In this study, a novel immobilized cell bioreactor, where <em>Clostridium ragsdalei</em> was grown, was designed and used to achieve an efficient production of ethanol regarding volumetric production. For this purpose, a 300 mL immobilized reactor filled with ceramic balls as immobilization material was set and operated at 30<sup>o</sup>C throughout the study where CO gas as the main substrate was fed at rate of 6 ml/min continuously. Results showed ethanol and acetic acid concentrations reaching up to 1.4 g/L and 0.2 g/L, respectively, after 600h with a volumetric production rate of 0,0023g ethanol/L/h. We believe, the ceramic ball was used for bioethanol production for syngas for the first time.</p> Simge Sertkaya Tugba Keskin Gundogdu Christian Kennes Nuri Azbar Copyright (c) 2021 ICONTECH INTERNATIONAL JOURNAL https://creativecommons.org/licenses/by-nc-nd/4.0 2021-09-25 2021-09-25 5 3 13 20 10.46291/ICONTECHvol5iss3pp13-20 English Estimating Fatigue of Nr45 Natural Rubber Used in Crank Pulley https://icontechjournal.com/index.php/iij/article/view/186 <p>Rubber is used as a vibration damper in many engineering applications, especially in the automotive industry. Rubber is used to dampen torsional vibration in internal combustion engines. Therefore, crank pulleys are used to dampen the crankshaft in a certain frequency range. Rubber durability is very important for the crank pulley to perform its duty for a long time. In this study, the dynamic life of NR45 natural rubber with two different mixtures used in crank pulleys was determined by the prepared test approach. A metal-rubber component structure used in the slip test samples was formed and produced. The metal-rubber component is left to force the rubber in the vertical direction with its natural frequency and specified amplitude to simulate torsional vibration in crank pulleys. A test setup design was carried out to force the metal-rubber component at the determined frequency. In the study, life expectancy estimates based on amplitude and frequency were created on experimental data.</p> Cihangir Kaplan Cem Güleç Mesut Arıkoğlu Copyright (c) 2021 ICONTECH INTERNATIONAL JOURNAL https://creativecommons.org/licenses/by-nc-nd/4.0 2021-09-26 2021-09-26 5 3 21 30 10.46291/ICONTECHvol5iss3pp21-30 An Overview of the Classification Problem in Unbalanced Datasets Using the Statistical Construction of European Community Economic Activities https://icontechjournal.com/index.php/iij/article/view/184 <p>The use of classical classifiers in unbalanced and multi-class data sets has always been a problem. In this study, a text mining work has been applied with well-known classifiers on the definitions of Statistical Construction of Economic Activities (NACE) codes in the European Community. In the study, first of all, the application was made on the unbalanced structure of the original data, then the performance measurement was performed by retesting the result data by making it balanced by weighting on a class basis. Common classifiers such as Decision Trees, Naiv Bayes, Support Vector Machines, Diametric Based Functions and Random Forest algorithms were used in the tests. The study showed us that as a result of data balancing of Decision Trees, the F-score value increased from 17.43% to 92%, giving the best performance.</p> Yasin Bektas Jale BEKTAŞ Copyright (c) 2021 ICONTECH INTERNATIONAL JOURNAL https://creativecommons.org/licenses/by-nc-nd/4.0 2021-09-25 2021-09-25 5 3 31 37 10.46291/ICONTECHvol5iss3pp31-37 Prediction of Labor Activity Recognition in Construction with Machine Learning Algorithms https://icontechjournal.com/index.php/iij/article/view/175 <p>It is essential that the control and management of the work of labors in construction project management is effective. In this study, it is aimed to building artificial intelligence models to recognition on activities in a construction work to effectively utilization project management and control. In accordance with this purpose, 3-axis accelerometer, gyroscope, and magnetometer data were obtained from the labors through the sensor to predict the activities determined for a construction work. These raw data were made compliance for the model by going through a series of preprocessing applications. These data are trained and modeled with basic machine learning algorithms logistic regression, SVC, DT and KNN algorithms. According to the results of the analysis, the best prediction was obtained with the SVC algorithm with an accuracy of 90%. In other algorithms, respectively, 87% accuracy was contrived in the KNN algorithm, and approximately 80% accuracy in the logistic regression and DT algorithms. According to these values, it has been observed that the activities performed in a construction work can be estimated at a high rate. In this way, at the construction sites, it can be automatically determined which work the laborer do at a certain accuracy rate.</p> Ibrahim Karatas Abdulkadir BUDAK Copyright (c) 2021 ICONTECH INTERNATIONAL JOURNAL https://creativecommons.org/licenses/by-nc-nd/4.0 2021-09-25 2021-09-25 5 3 38 47 10.46291/ICONTECHvol5iss3pp38-47 CHARACTERIZATION OF CARBON FIBERS DERIVED FROM THERMALLY STABILIZED POLY(HEXAMETHYLENE ADIPAMIDE) PRECURSOR FIBERS https://icontechjournal.com/index.php/iij/article/view/164 <p>The thermal oxidative stabilization and carbonization processes of poly(hexamethylene adipamide) or (polyamide 66) fibers were accomplished to transform into carbon fibers. Polyamide 66 fibers were pretreated with a ethanol solution of cupric chloride followed by a stabilization process in the air atmosphere. Carbonization experiments were executed at temperatures of 500, 700, 900, and 1100°C utilizing heating rate of 2.5 °C/min. Carbonization experiments were performed at temperatures between 500 and 1100°C employing the rises of 100°C. X-ray diffraction analysis of the carbon fibers shown a highly disordered carbon structure developed during the carbonization process. The values of fiber diameter, linear density, volume density, carbon fiber yield, elemental analysis, and electrical properties revealed a strong dependence on the carbonization temperature. As an insulating material, the polyamide 66 or PA66 precursor was transformed to a semiconducting stage after the thermal stabilization and carbonization processes. The current study demonstrated how processing parameters influence the structure and characteristics of carbon fibers produced from poly(hexamethylene adipamide) fibers.</p> Mahbubor Rahman TUBA DEMIREL İsmail Karacan Copyright (c) 2021 ICONTECH INTERNATIONAL JOURNAL https://creativecommons.org/licenses/by-nc-nd/4.0 2021-09-25 2021-09-25 5 3 48 55 10.46291/ICONTECHvol5iss3pp48-55 TECHNO-ECONOMIC ANALYSIS OF AN OFF-GRID HYBRID ENERGY SYSTEM WITH HOMER PRO https://icontechjournal.com/index.php/iij/article/view/191 <div class="page" title="Page 1"> <div class="section"> <div class="layoutArea"> <div class="column"> <p>The decrease in fossil-based energy sources and increasing environmental problems increase the tendency to renewable energy sources day by day. The potential of renewable energy sources differs according to the region where the energy will be produced. For this reason, it is crucial to conduct a good feasibility study that deals with the selected systems from a technical and economic point of view before making an investment decision on energy conversion systems based on renewable energy sources.</p> <p>In this study, the most suitable equipment and capacities were investigated by examining the techno-economic analysis of a hybrid system created with wind-solar renewable energies for a detached house, which is considered off-grid, in a rural area of Tekirdağ province (40o58.7ı N, 27o30.7ı E). Investigations were carried out using the HOMER Pro (Hybrid Optimization Model for Electric Renewable) program. The wind and solar energy potential of Tekirdağ province were obtained from the NASA renewable energy resources database added to the HOMER Pro program. The daily electricity requirement of the sample house was chosen as 11.27 kWh, and the current peak electrical load was chosen as 2.39 kW. A wind turbine is connected to the AC busbars, solar collectors and battery group connected to the DC busbars, and a converter that converts energy between AC and DC busbars in the energy conversion system. In order to determine the optimum capacities of the system elements, 27486 different simulations were performed by HOMER Pro. The selection of the most suitable system among these was determined according to the lowest net present cost (NPC) value. In addition, the energy production capacities that will occur in the case of different wind speeds were also investigated. Accordingly, the system to be installed with a solar panel with a capacity of 6.25 kW, PV-MPPT with a capacity of 1 kW, 2 wind turbines with a capacity of 1 kW, 8 Lithium-ion batteries with a capacity of 6V-167 Ah, and a converter with a capacity of 2.5 kW has been determined will generate electrical energy of 5433 kWh per year. In addition, it has been determined that 61.8% of this produced energy will be obtained from solar energy and 38.2% from wind energy, and the simple payback period of the investment will be 14 years. It is thought that this study will provide valuable information to researchers and investors.</p> </div> </div> </div> </div> Ahmet Erhan AKAN Copyright (c) 2021 ICONTECH INTERNATIONAL JOURNAL https://creativecommons.org/licenses/by-nc-nd/4.0 2021-09-25 2021-09-25 5 3 56 61 10.46291/ICONTECHvol5iss3pp56-61