Abstract: An operating method of a wireless communication device includes receiving a reference signal from a base station, estimating a first channel between the wireless communication device and the base station based on the reference signal, extracting, based on a first artificial intelligence model trained to reduce a difference between the first channel estimated by the wireless communication device and a second channel estimated by the base station, a feature including grouped attributes from the first channel, quantizing the grouped attributes using a codebook that is based on a second artificial intelligence model and by generating one or more indices of the codebook for each group of the attributes, and transmitting, to the base station, a bitstream including combination information of the indices of the codebook.

Abstract: Solid low foaming and low pH all-purpose cleaning and disinfectant compositions are disclosed. The solid disinfectant compositions comprise approximately 50% w/w to approximately 75% w/w of citric acid encapsulated by a binder and approximately 1% to approximately 5.5% w/w of sodium benzoate. The solid cleaning and disinfectant compositions comprise approximately 50% w/w to approximately 75% w/w of citric acid encapsulated by a binder; approximately 1% to approximately 5.5% w/w of sodium benzoate; and approximately 10% w/w to approximately 15% w/w of sodium lauryl sulfate. The solid compositions are dissolved in water to produce a disinfectant solution comprising approximately 1.2% w/v to approximately 2% w/v citric acid and approximately 0.083% w/v to approximately 0.15% w/v sodium benzoate. A 10 minute contact time with the disinfectant solution provides a 5 log10 reduction in Staphylococcus aureus on a surface.