A novel ZVS full-bridge converter

Conventional soft switching techniques are promising for improvement of efficiency in full bridge converters. However, efficiency of converters with employing such techniques is restricted due to narrow range of zero voltage switching (ZVS). In such situation, several methods have been proposed in the literature to cope with wide range of ZVS from no load to maximum load. The extra circuitry added to achieve a wide range of ZVS generates more conduction losses in a converter and increase cost of converter. In this paper, a novel ZVS full bridge converter is proposed to eliminate limitations of narrow range ZVS, improved efficiency and reduced cost. The circuit diagram, operation principle of proposed converter is explained and analyzed theoretically in detail. In addition, the proposed converter is built and experimental results are provided to verify the novel ZVS full bridge converter

Mitigation of Common mode Noise for PFC Boost Convertor by Balancing Technique

The PFC Boost Converter is an integral part of modern power supplies to improve power factor in electronic devices. The inherent problem associated with it is common mode (CM) Electromagnetic interference (EMI) noise arising due to the higher switching transition rate (dv/dt). The main coupling path for the CM noise is provided by parasitic capacitance occurring between the switching node and ground. In this scenario, it is important to identify feasible solutions for CM noise reduction. This paper therefore develops a circuit model for a boost PFC converter allowing detailed analyses of the performance of this type of converter. It includes all parasitic components along the CM noise path. Using this CM noise model, a novel balancing approach is proposed that mitigates CM noise in a PFC boost converter. Validation of the new design approach is supported by experimental results demonstrating substantial noise reduction for a balanced PFC boost converter

CM noise reduction of isolated converter by balancing technique

Common mode (CM) EMI noise in an isolated converter is mainly due to parasitic capacitance occurring within the SMPS. It flows through the transformer coupling capacitance and the parasitic capacitance of switching MOSFETs and rectification diodes. Several techniques have been proposed in the literature to reduce CM noise. The most common techniques are compensation, shielding, and the balancing-shielding technique. In this paper, a new balancing technique is described to reduce the noise of both parasitic capacitances of MOSFETs and transformer inter-winding capacitance. Analysis is presented to demonstrate the efficacy of the compensation method and the resultant reduction in EMI noise. Finally, the practical measurement results obtained from a practical implementation of the new technique in a flyback converter topology, are presented as verification of the benefits of the approach in comparison to the conventional method

Histopathological image analysis : a review

Over the past decade, dramatic increases in computational power and improvement in image analysis algorithms have allowed the development of powerful computer-assisted analytical approaches to radiological data. With the recent advent of whole slide digital scanners, tissue histopathology slides can now be digitized and stored in digital image form. Consequently, digitized tissue histopathology has now become amenable to the application of computerized image analysis and machine learning techniques. Analogous to the role of computer-assisted diagnosis (CAD) algorithms in medical imaging to complement the opinion of a radiologist, CAD algorithms have begun to be developed for disease detection, diagnosis, and prognosis prediction to complement the opinion of the pathologist. In this paper, we review the recent state of the art CAD technology for digitized histopathology. This paper also briefly describes the development and application of novel image analysis technology for a few specific histopathology related problems being pursued in the United States and Europe

The Specifics of Outsourcing Companies in The Republic of Belarus

Материалы XI Междунар. науч. конф. студентов, аспирантов и молодых ученых, Гомель, 17-18 мая 2018 г

Improving the efficiency of repair-technical service of production by using the concept of total productive maintenance

Материалы XVIII Междунар. науч.-техн. конф. студентов, аспирантов и молодых ученых, Гомель, 26–27 апр. 2018 г

A Survey for Need Assessment to Classify Learning Styles of Students Studying in Master Degree Programs at Universities

Students’ learning is highly subjective owing to their individual differences, environment and background which decide their learning styles. The purpose of this study was to explore learning styles of university students owing to generic role in their learning. There is need to assess whether students of different universities with different backgrounds but with same discipline prefer same or different learning styles. Four general universities were selected; two from each, public sector and privatesector.314 students were involved in the study from selected universities. A questionnaire was developed in the light of literature to explore learning styles of students mainly based on Grasha Reichmann Learning Style Survey (1974). Survey research design was used to collect data. The number of students against every learning style was calculated through statistical distribution. To infer the significance of results, t-test and ANOVA were applied. The findings showed that learning styles were closely linked gender wise. Further, there was no vast difference in learning styles of the students in respect of public and private sector universities. Subject based results are generally aligned but there are variations in couple of subjects like mass communication. The study concludes that students use variety of learning styles in different situations. If teacher used teaching style compatible to preferred students learning style then they would take more interest in the lesson and learn better

CM Noise Reduction of Isolated Convertor by Balancing Technique

Common mode (CM) Electromagnetic interference (EMI) noise in an isolated converter is mainly due to parasitic capacitance occurring within the SMPS (Switch-mode Power Supply). It flows through transformer coupling capacitance and the parasitic capacitance of MOSFETs and diodes. Several techniques have been proposed in the literature to mitigate the common mode noise flowing through transformer windings. Transformer shielding is one of the most effective methods to reduce EMI noise between the primary and secondary windings, however. However, further improvement should be possible by developing more precise models. In this paper, we develop an EMI noise model for an isolated converter that allows detailed performance analysis. It incorporates the parasitic elements of the converter components and also the coupling capacitance of the transformer. Using this model we propose a new balancing technique to mitigate the CM noise of the isolated converter with modified transformer. The proposed method is applied to an isolated converter and experimental results are provided to verify the novel balancing technique