Light-emitting diodes (LEDs), which will be increasingly used in lighting technology, will also allow for distribution of broadband optical wireless signals. Visible-light communication (VLC) using white LEDs offers several advantages over the RF-based wireless systems, i.e., license-free spectrum, low power consumption, and higher privacy. Mostly, optical wireless can provide much higher data rates. In this paper, we demonstrate a VLC system based on a white LED for indoor broadband wireless access. After investigating the nonlinear effects of the LED and the power amplifier, a data rate of 1 Gb/s has been achieved at the standard illuminance level, by using an optimized discrete multitone modulation technique and adaptive bit- and power-loading algorithms. The bit-error ratio of the received data was 1.5 10^(-3), which is within the limit of common forward error correction (FEC) coding. These results twice the highest capacity that had been previously obtained

In this paper, we experimentally realized a gigabit-class indoor visible light communication system using commercially available RGB White LED and exploiting an optimized DMT modulation. We achieved data rate of 1.5 Gbit/s with single channel and 3.4 Gbit/s by implementing WDM transmission at standard illumination levels. In both experiments, the resulting bit error ratios were below the FEC limit. To the best of our knowledge, these values are the highest ever achieved in VLC systems.

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We experimentally prove high-speed underwater optical wireless transmission over 2.5 m distance, using different bit rates and modulation schemes. The system uses two low-cost Light Emitting Diodes (LEDs) arrays as optical transmitter and an avalanche photodiode module as receiver. The measurements are taken using an outdoor water tank having 3.3 m diameter, where two waterproof boxes containing the transmitter and the receiver are fixed underwater at the inner borders. We test 6.25 Mbit/s with Manchester coding, 12.5 Mbit/s with NRZ 8b/10b coding and 58 Mbit/s with Discrete Multitone modulation. Bit Error Rate measurements are collected over several hours under typical summer sunlight illumination conditions. In all the experimental conditions we achieve error free transmission

Background: Job burnout is a major issue for workers in the banking sector. Many employees report feeling exhausted and want to leave their jobs due to the extra pressure and workload from their superiors and clients. They also report not being well compensated for their hard work, which they believe they do to provide the best service to their clients. Methods: A cross-sectional study was made in various banks in different cities of Pakistan. An adapted questionnaire, including the effort-reward imbalance scale, psychological capital, and Maslach burnout inventory general survey were used to collect data from 1,778 male and female bank employees. Results: There was a significant and positive relationship between extrinsic effort and over-commitment on the one hand, and emotional exhaustion and depersonalization on the other. It was also found that reward was negatively associated with emotional exhaustion and depersonalization. However, reward had a positive association with personal accomplishment. There was a gender difference in the mediating effect of psychological capital on stress at work and job burnout. Conclusion: Male attitudes to work tend to be motivated by reward and appreciation, whereas females tend to demand a better working environment. To reduce job, burnout suitable interventions could be introduced for bank employees, whilst management support plays an important role in increasing or decreasing stress in employees.