Cite : Angel Marinov.(2014).Study of Power Loss Reduction in SEPR Converters for Induction Heating through Implementation of SiC Based Semiconductor Switches.TEM Journal, 3(3), 197-201.

Abstract : This paper presents a power loss analysis for a Single Ended Parallel Resonance (SEPR) Converter used for induction heating. The analysis includes a comparison of the losses in the electronic switch when the circuit is realized using a conventional Silicon (Si) based IGBT or when using Silicon Carbide (SiC) based MOSFET. The analysis includes modelling and simulation as well as experimental verification through power loss and heat dissipation measurement. The presented results can be used as a base of comparison between the switches and can be a starting point for efficiency based design of those types of converters.

Keywords — Induction Heating, SEPR converter, SiC MOSFET, Power Losses.

Cite : Bojan Ivetic, Dragica Radosav.(2014).The Application of Neural Networks in Balancing Production of Crude Sunflower Oil and MealTEM Journal, 3(3), 202-209.

Abstract : The aim of the research is to predict specific output characteristics of half finished goods (crude sunflower oil and meal) on the basis of specific input variables (quality and composition of sunflower seeds), with the help of artificial neural networks. This is an attempt to predict the amount much more precisely than is the case with technological calculations commonly used in the oil industry. All input variables are representing the data received by the laboratory, and the output variables except category % of oil which is obtained by measuring the physical quantity of produced crude sunflower oil and sunflower consumed quantity of the processing quality. The correct prediction of the output variables contributes to better sales planning, production of sunflower oil, and better use of storage. Also, the correct prediction of technological results of the quality of crude oil and meal provides timely response and also preventing getting rancid and poor-quality oil, timely categorizing meal, which leads to proper planning and sales to the rational utilization of storage space, allows timely response technologists and prevents the growth of microorganisms in the meal.

Keywords — neural networks, artificial intelligence, crude sunflower oil, balancing production.

Cite :  Farhad Kia, Gábor Jeney, János Levendovszky.(2014).Loss-minimal Algorithmic Trading Based on Levy Processes .TEM Journal, 3(3), 210-215.

Abstract :   In this paper we optimize portfolios assuming that the value of the portfolio follows a Lévy process. First we identify the parameters of the underlying Lévy process and then portfolio optimization is performed by maximizing the probability of positive return. The method has been tested by extensive performance analysis on Forex and SP 500 historical time series. The proposed trading algorithm has achieved 4.9\% percent yearly return on average without leverage which proves its applicability to algorithmic trading.

Keywords - Levy Process, Algorithmic trading, Portfolio optimization, FOREX.

Cite :  Daniela Koltovska, Kristi Bombol.(2014).Intelligent Agent Based Traffic Signal Control on Isolated Intersections.TEM Journal, 3(3), 216-222.

Abstract :  The purpose of this paper is to develop an adaptive signal control strategy on isolated urban intersections. An innovative approach to defining the set of states dependent on the actual and primarily observed parameters has been introduced. ?he Q–learning algorithm has been applied. The developed self-learning adaptive signal strategy has been tested on a re?l intersection. The intelligent agent results have been compared to those in cases of fixed-time and actuated control. Regarding the average total delay, the total number of stops and the total throughput, the best results have been obtained for unknown traffic demand and over-capacity.

Keywords - adaptive control, isolated intersections, artificial intelligence, intelligent agent, Q-learning.

Cite :  Kadir Akgöl, Metin Mutlu Aydin, Özcan Asilkan, Banihan Güna.(2014).Prediction of Modal Shift Using Artificial Neural Networks.TEM Journal, 3(3), 223-229.

Abstract :  Various public transport concepts have been developed to provide solutions to the ever growing problem of traffic in modern times. For instance, intelligent subscription bus service is one of them. This concept aims to provide a means of transport at near private car comfort as well as at near public transport cost. By this means, a shift from other modes of transport, especially private car, to public transport is aimed to encourage use of public transport. An artificial neural network model has been developed in this study to be able to calculate modal shift using three sources of data obtained from two questionnaire surveys conducted at Akdeniz University campus and a computer model's output (based on shortest route algorithms). The relationship between the results of the second questionnaire survey and the other data have been entered into Weka and Rapid Miner programs, the accuracy of this machine learning has been calculated and finally the modal shift originated by the intelligent subscription bus services has been estimated. The findings have yielded very reliable results which revealed the potential of applying the technique easily to similar problems.

Keywords - Flexible public transport systems, artificial neural networks, modal shift.

Cite :  Iliyan Iliev.(2014).Polar Response of a Circular Piston. TEM Journal, 3(3),230-234.

Abstract :  The current paper reviews theoretically and examinesexperimentally the polar plotof a loudspeakerin the far and near field.An original equation for sound pressure calculation in the near and far field is proposed. An experiment is conducted to confirm the theoretical data and the accuracy of the proposed expression. Several conclusions are drawn from the analysis of the study.

Keywords - polar plot, near field,far field, sound pressure, measurements.

Cite :  Sevde Stavreva, Marko Serafimov.(2014).Computational Fluid Dynamics (CFD) Analysis for Predicting the Airflow in a Data CentreTEM Journal, 3(3), 235-243.

Abstract :  This paper studies the high density data centre with 266.4 m2 area, and it focuses on defining the heat profile of the centre, as well as on the airflow in the centre. To this purpose, the necessary measurements in the data centre have been taken, and a detailed model in the computational fluid dynamics program package PHOENICS has been elaborated. The model simulations yielded the fields of temperature, velocity and pressure throughout the center, as well as the complete image of the airflow in the center.The results helped to detect the weak points and to draw conclusions regarding upgrading the defined working conditions in the data-com equipment.

Keywords - data centre, data-com equipment, air-conditioning, simulation, model.

Cite :  Borislav Dimitrov, Maik Streblau, Angel Marinov.(2014).An Approach for Designing a Complex Inductor –Workpiece system for Induction Heating.TEM Journal, 3(3), 244-249.

Abstract :  The current paper presents an approach for designing a complex electromagnetic system consisting of an inductor and a workpiece. The approach is based on known methodologies and includes numerical methods for modelling. Using this approach, a methodology for designing the geometry of the inductor, based on the geometry of the workpiece, is suggested. The methodology can be used to develop designs with uniform temperature field, improved quality of the heating process and increased energy efficiency. Experimental study that verifies the advantages of the methodology is presented.

Keywords - design methodology, induction heating, numerical methods.

Cite :  Veselin Hadzhiev.(2014).More on Measuring the Overall Revealed Comparative AdvantageTEM Journal, 3(3), 250-256.

Abstract :  The overall revealed comparative advantages approach aims to summarize the divergent expression of comparative advantages by commodity groups and countries. It represents an alternative to the traditional approach of Bella Balassa, Thomas Vollrath and others. The innovativeness of the overall revealed comparative advantages approach preconditions a certain prudence with regard to its use and interpretation. It is necessary to explore the potential of the approach in different conditions and different circumstances. It was found that the approach of overall revealed comparative advantages is resistant to the Euclidean distances and commodity classifications used for metrification. It has the potential to synthesize uniformly divergent changes in specialization by country and commodity groups and is a useful tool for the analysis of comparative advantages.

Keywords - Revealed comparative advantages, Specialization, Foreign trade.

Cite :  Aleksandar Dejanovski, Dori Pavloska Gorgioska.(2014).The Impact of the Required Reserve on the Monetary Multiplication in the Republic of Macedonia. TEM Journal, 3(3), 257-261.

Abstract :  One of the primary and most important tasks of any central bank is conducting monetary policy in the state. In Macedonia the only central and issuing bank is the National Bank of Macedonia, which is responsible for the monetary and financial stability in the country, while performing important functions, without which the overall economic and financial system could not exist. In exercising its functions, the National Bank of Macedonia uses a set of economic instruments and policies, from which in RM the most efective is the required resserve. This monetary tool is showing the best results in developing countries where the financial markets are not developed and where there is a high concentration of the banking sector (in RM banks occupy a good 98% of total financial institutions). The role of the reserve will be analyzed through the prism of its effects on the process of multiplication the money supply in the country and its contribution to generating or withdrawal of money by the central bank. The main goal of the paper is to research the required reserve, as a monetary instrument, and to qualify its impact on the monetary creation in the Republic of Macedonia. The basic methods, used in this paper are the positive analysis, comparative analysis and deductive approach.

Keywords - Required reserve ratio, financial system, The National Bank of Macedonia, monetary policy.

Cite :  Simões, Dora, Pinheiro, Margarida M., Amaral, Claudia.(2014).How the use of Different Teaching and Learning Methodologies Echoes in Learners: The Students’ Perspectives.TEM Journal, 3(3), 262-271.

Abstract :  The purpose of this paper is to contribute to the discussion on how the use of different teaching and learning methodologies: (1) models students’ perceptions and expectations; (2) is reflected on the impact different communication mechanisms have in students’ engagement; and (3) fosters students’ interest.The paradigms of resilience, persistence and determination are pertinent aspects students point out that may justify distinct responses to several communication mechanisms, and differentiated interests towards a set of methodological resources.

Keywords - teaching and learning methodologies, higher education institutions, students, technologies, learning styles.