OpenAI is preparing to launch a new artificial intelligence model that it said is capable of more advanced human-like reasoning than its current offerings, ratcheting up the competition with rivals such as Alphabet Inc.’s Google.The new o3 model, unveiled during a livestreamed event on Friday, spends more time computing an answer before responding to user queries, with the goal of solving more complex multi-step problems. The company will also introduce a smaller version of the model called o3-m...