Informatics Publishing Limited

S. Robinson ¹, S. Jasmine ¹, R. Pavithra ¹

Affiliations
1 Department of Electronics and Communication Engineering, Mount Zion College of Engineering and Technology, IN

Abstract

Free Space Optical (FSO) communication is being realized as an effective solution for future accessing networks, offering light passed through air. The performance of FSO can be primarily degraded by various atmospheric attenuation namely, rain, fog, haze and snow. At present, hybridization of Dense Wavelength Division Multiplexing (DWDM) with Coarse Wavelength Division Multiplexing (CWDM) becomes necessary to scale the speed and high bandwidth of the services. In this paper, hybrid WDM system is proposed, designed and the network parameters such as Bit Error Rate (BER), Quality Factor and receiver sensitivity are analyzed with respect to link distance for various weather conditions. For investigation, 4 CWDM and 8 DWDM channels are considered whose corresponding channel spacing is 20nm and 0.8nm, respectively. From the simulation, it is investigated that the average link distance of proposed hybrid WDM-FSO system for DWDM and CWDM system at very clear condition are around 810km and 780km. The proposed hybrid WDM based FSO system is designed to handle the quality of transmission for 12 users, each at a data rate of 2.5Gbps.

Keywords

FSO, Hybrid WDM, CWDM, DWDM, BER.

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G. Vidhya ¹, R. Pavithra ¹

Affiliations
1 Electronics and Communication Engineering Department, Chennai, IN

Abstract

FFT plays a very important role in real-time signal processing applications. This paper concentrates on the design of an FFT processor that computes 16-point FFT, based on Decimation-In-Domain (DIT), radix-2 algorithm. A codesign concept is used in which 16-point FFT is completed in a Xilinx Spartan-3 FPGA chip that contains MicroBlaze processor where the hardware is modeled by VHDL and the software is written in Impulse C. FPGA EDK hardware is used to simulate and synthesize the VHDL and Impulse C. A radix 2 FFT algorithm is designed using VHDL structural level modeling and this synthesizes and creates the bit file. The Impulse C helps to create the executable file in software flow side. The Xilinx Platform Studio (Embedded Development Kit – EDK) is used to control the FPGA and both the files (bit and executable) are loaded into the FPGA kit. The FFT inputs are fed to the FPGA via Xilinx Platform Studio and the FFT equivalent outputs are displayed in PC through UART. The synthesis results show that the computation for calculating 16-point FFT is efficient in terms of resource utilization and power consumption.

Keywords

Embedded Development Kit, FPGA, Impulse C, VHDL.

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R. Pavithra ¹, C. Maheswari ¹

Affiliations
1 Dept of EEE, Dr.N.G.P IT, Coimbatore, IN

Abstract

The work presented in this paper concerns the speed control of a switched reluctance motor (SRM) by use of a Maximum Power Point Tracking (MPPT) strategy applied to a SEPIC converter. A PV generator is used for energy supply. Fuzzy logic control has become an important methodology in many fields. This paper proposes a Fuzzy Logic Controller (FLC) to control the speed of SRM motor. The main objective of this work is to compare the operation of P& PI based conventional controller and gives the effective performance using Fuzzy Logic Control. The present work concentrates on the design of a fuzzy logic controller for the SRM speed control. Thus the result of applying fuzzy logic controller to a SRM drive gives the best performance and high robustness than a conventional P&PI controller. Simulation is carried out using Matlab simulink.

Keywords

Switched Reluctance Motor (SRM), Photovoltaic’s, MPPT Control, Sepic Converter, Fuzzy Logic Control.

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R. Pavithra ¹, D. Theerthika ¹, B. Uma Bharathi ¹, S. Arun Kumar ¹, K. Manikandan ¹

Affiliations
1 Department of Public Health Dentistry, Sri Venkateswara Dental College and Hospital, Thalambur, Chennai – 600130, Tamil Nadu, IN

Abstract

Background: Procrastination is considered problematic when it affects normal day-to-day functioning. It can serve as a deterrent among undergraduate dental students both for their academic and career growth. Behaviour modifications are required to change this negative behaviour and Sense of Coherence is one such approach. Aim: To assess the relationship between Sense of Coherence and Procrastination among a group of undergraduate dental students in Chennai city. Material and Methods: A cross sectional questionnaire study was conducted among 358 undergraduate dental students. Thirteen item Sense of Coherence scale and Lay’s Procrastination scale were used to collect data about Sense of Coherence and Procrastination among undergraduate dental students respectively, using google forms. One-way ANOVA and Independent T test were used to test for difference in mean scores between groups based on year of study and gender, respectively. Pearsons correlation coefficient followed by Simple Linear Regression was performed to test for association between Sense of Coherence and Procrastination. Results: The overall mean Sense of Coherence score of the study participants was 49.52 ± 8.13. The overall mean Procrastination score of the study participants was 56.58 ± 10.02. Pearson’s Correlation Coefficient revealed a negative correlation (r = -.255) between Sense of Coherence and Procrastination (p = .000) indicating that with an increase in Sense of Coherence, Procrastination decreases. In tandem, the third year students with lowest Sense of Coherence score showed highest procrastination. Conclusion: Procrastination is negatively associated with Sense of Coherence and hence behaviour modification interventions based on Sense of Coherence are required, to be customized and incorporated in dental curriculum to reduce procrastination among undergraduate dental students.

Keywords

Behaviour Modification, Dental, Procrastination, Sense of Coherence, Students, Undergraduates.

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