Mepco Schlenk Engineering College

About: Mepco Schlenk Engineering College is a based out in . It is known for research contribution in the topics: Wavelet & Wavelet transform. The organization has 1307 authors who have published 1665 publications receiving 18690 citations.

Design of efficient massive MIMO for 5G systems — Present and past: A review

Abstract: In this survey paper, the ground work on Massive Multiple Input — Multiple Output (mMIMO) is concentrated by studying the various existing techniques in the system design for fifth generation wireless communications. The service quality of 5G systems can be enhanced in terms of throughput, latency, peak data rate along with spectral and energy efficiency. Though there exist, new methodologies, techniques and architectures including Cognitive Radio Networks, D2D communications for designing and implementing 5G networks, the mMIMO utilizes spatial multiplexing for capacity improvement and remains robust across intentional jamming thereby playing a key aspect in the 5G system development. The efficient design of mMIMO still remains an open problem in the present research. This paper analyses the existing techniques in the development of mMIMO specifically concentrating on energy & spectral efficiency and discusses the challenges in the system design.

Combating the effect of nonlinearities in DWDM system

Abstract: In Fiber optic communication, Dense Wavelength Division Multiplexing system (DWDM) is used to increase the capacity and to satisfy the need of enormous bandwidth utilization. In this system more number of channels with different wavelength passed through Single Mode Fiber (SMF). Eventhough, there is an impact of parameters such as input power, channel spacing and frequency response. To achieve high data rates for long haul communication the launching power for transmission should be high. Due to this, the system behave from linear to nonlinear response leads to the unwanted effects. Generally the DWDM system affects by nonlinear effects such as Simulated Raman Scattering (SRS), Cross-Phase Modulation (XPM) and Four-Wave Mixing (FWM). These effects severely degrade the system performance. In this paper, the impact of FWM and SRS effects were analyzed for different number of channels with power level varied from −10 dBm to 10 dBm. The FWM effect was suppress by introducing the Circular Polarizers (CP) alternatively in each channel before multiplexing and the SRS effect was reduced by using Super Gaussian Filter after optical fiber.

Detection of architectural distortion in mammogram image using wavelet transform

Abstract: In this paper, we present methods for the detection of sites of architectural distortion in prior mammograms of interval-cancer cases. We observed that screening mammograms obtained prior to the detection of cancer could contain subtle signs of early stages of breast cancer, in particular, architectural distortion. This method uses wavelet transform to improve the accuracy of detection. Before using wavelet transform the image is preprocessed by Otsu threshold method, followed by filtering using morphological filtering. Analysis made using phase portrait analysis, angular spread of power analysis. Further fractal analysis, Laws' texture energy measures derived from geometrically transformed regions of interest (ROIs), and Haralick's texture features are determined. The architectural distorted areas are viewed in marked curved lines which are obtained by diluting image and maximizing the size of the image, if it get vanished it comes under noise category and it is filtered out by morphological filter, if it remains, it comes under architectural distorted region. The accuracy of detection is improved by applying wavelet transform.

Chitosan nanoparticle-mediated delivery of curcumin and phycocyanin for photodynamic therapy against biofilm forming bacteria

Abstract: Bacteria within biofilm display resistance to host defense and conventional antimicrobial agents. The present study was aimed to reduce biofilm formation by Staphylococcus aureus and Pseudomonas aeruginosa using photodynamic therapy. Natural photosensitizers such as curcumin and phycocyanin were encapsulated within chitosan nanoparticles synthesized by ionic gelation method. It was characterized by SEM, TEM, Particle size analyzer, UV-Vis analysis, FTIR, XRD and TGA. The antibacterial activity of curcumin and phycocyanin delivered through chitosan nanoparticles against S. aureus and P. aeruginosa was investigated by well diffusion assay. Photodynamic antibiofilm activity was investigated by crystal violet assay. Generation of reactive oxygen species by photosensitizers was recorded using spectrophotometer. The chitosan nanoparticles encapsulated with photosensitizers were spherical in shape with an average size of 20 nm. Encapsulation efficiency of chitosan nanoparticles was 36.45% for phycocyanin and 44.96% for curcumin. The antibacterial and antibiofilm activity of curcumin and phycocyanin increased with concentration. Curcumin and phycocyanin reduced less than 0.5% of biofilm formed by S. aureus and P. aeruginosa in dark treatment. Illumination reduced 2.57% and 2.18% of biofilm formed by S. aureus and P. aeruginosa respectively. Photodynamic activity of curcumin and phycocyanin delivered through chitosan nanoparticles at 100 _g/mL reduced 92% and 88% of biofilm formed by S. aureus and P. aeruginosa respectively. The dose dependent photodynamic antibacterial activity was found to be mediated through the formation of reactive oxygen species. The viability of fibroblast cells was 90% in phycocyanin, 85% in curcumin, 98.5% in sham control CNPs and 88% in CNPs encapsulated with PS at 80 _g/mL. Thus, the study demonstrated the significant reduction of biofilm formed by clinical isolates through photodynamic therapy without detrimental effect to human fibroblast cells.