A multiwavelength widely tunable Brillouin optical comb with an enhanced reverse-S-shaped feedback coupling assisted by out-of-cavity optical amplifier is demonstrated. The enhancement is done by locating the amplifier and the Brillouin pump into the reverse-S-shaped fiber section. The oscillating modes in the cavity are directly influenced solely by the Brillouin gain. A wide tuning range of 45 nm is obtained that is only limited by the erbium amplification bandwidth. An average of eleven laser lines that can be tuned to over 45 nm wavelengths is obtained at 40% optimum output coupling ratio.

Optimization of Brillouin pump (BP) wavelength location on tunable multiwavelength Brillouin-erbium fiber laser (BEFL) with BP pre-amplified technique is experimentally investigated. The tunable multiwavelength BEFL is achieved by utilization a tunable bandpass filter in a laser cavity. The optimum BP power and BP wavelength location within the filter bandwidth is determined in order to obtain the maximum stable output channels. Optimum distance of launching the BP wavelength is found at 0.80 nm shorter from the center wavelength of the filter bandwidth. 15 stable output channels are achieved from the tunable fiber laser system within the optimum range of BP power which is found to be between 5.2 to 5.7 dBm.

Social networking has opened up new avenues for learning and knowledge sharing. Because of its document exchange, virtual communication, and knowledge production capabilities, social media is a helpful tool for learning and teaching. This research embraces multiple goals. First, this study examines Bangladeshi university students’ social value, communication and collaboration, trust, and the perceived benefits of knowledge sharing through social media in academic advancement. The second goal is to examine how families and technology support mediate those aspects of social media knowledge sharing with student academic development. This study uses the Technology Acceptance Model and Social Exchange Theory as an example of how knowledge sharing through social media with the help of family and technology impacts academic progress among Bangladeshi university students. This paper uses PLS-SEM on the survey data from 737 Bangladeshi students to test the model with the help of SmartPLS 4. Social value, communication and collaboration, trust, and the perceived benefits of sharing knowledge through social media significantly enhance Bangladeshi students’ academic growth. In the case of mediation, family and technological support mediate the relationship between communication and collaboration, trust, perceived benefits and academic development. However, there is no mediation between the social value of knowledge sharing in social media and students’ academic development. The article concludes with implications, limitations, and future research.

An enhanced multiwavelength Brillouin‐erbium fiber laser with virtual mirror concept is demonstrated. The performance of three linear amplifier schemes is investigated and optimized. Wide tuning range of 39 nm and maximum of nine laser lines are achieved utilizing a 915 nm pump laser at 616 mW pump power. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2549–2553, 2013

In this paper, the &bit MCGXI-ICl 1 MCU micro controller is used to receive data speed data from Doppler radar speed sensor. Vehicle speeds are detected by Doppler radar speed sensor and then send to a micro controller. The micro controller is programmed to detect the signal and calculate the speed of vehicle, display data on LCD, and concurrently send data to PC through RS-232 port via Serial Communication Interface. The GUI for PC is developed with VI36 progranuning to rcceive data €rani micro controller and capture picturc. VI36 is programmed to manual capture an image and also auto capture and auto save an image in directory if vehicle speed is over speed limit selected from micro controller. Also Microsoft's Access database program is used to saveirecord data in a database.