A version of this story appears in the September 2020 issue of National Geographic magazine. Philadelphia detected its first case of a deadly, fast-spreading strain of influenza on September 17, 1918.

Adam Hayes, Ph.D., CFA, is a financial writer with 15+ years Wall Street experience as a derivatives trader. Besides his extensive derivative trading expertise, Adam is an expert in economics and ...

James Chen, CMT is an expert trader, investment adviser, and global market strategist. Gordon Scott has been an active investor and technical analyst or 20+ years. He is a Chartered Market Technician ...

Abstract: A parallel parking path planning method aiming at the automatic parking application scene of parallel parking in narrow space of urban roadside parking lot is proposed in the paper, based on ...

Abstract: Common cross-validation (CV) methods like k-fold cross-validation or Monte Carlo cross-validation estimate the predictive performance of a learner by repeatedly training it on a large ...

Lordosis is a curvature problem in the neck or lower back. If lordosis is not painful or severe, exercises and good posture can help. Severe lordosis with pain should be checked by a healthcare ...