共找到 20 条结果
There's still a slew of questions about why some people develop alpha-gal syndrome
Proximal Policy Optimization (PPO) is a ubiquitous on-policy reinforcement learning algorithm but is significantly less utilized than off-policy learning algorithms in multi-agent settings. This is often due to the belief that PPO is significantly less sample efficient than off-policy methods in multi-agent systems. In this work, we carefully study the performance of PPO in cooperative multi-agent settings. We show that PPO-based multi-agent algorithms achieve surprisingly strong performance in four popular multi-agent testbeds: the particle-world environments, the StarCraft multi-agent challenge, Google Research Football, and the Hanabi challenge, with minimal hyperparameter tuning and without any domain-specific algorithmic modifications or architectures. Importantly, compared to competitive off-policy methods, PPO often achieves competitive or superior results in both final returns and sample efficiency. Finally, through ablation studies, we analyze implementation and hyperparameter factors that are critical to PPO's empirical performance, and give concrete practical suggestions regarding these factors. Our results show that when using these practices, simple PPO-based methods can be a strong baseline in cooperative multi-agent reinforcement learning. Source code is released at \url{https://github.com/marlbenchmark/on-policy}.
A surprisingly simple fuel modification could help tackle one of diesel engines’ biggest problems: pollution。 Researchers reviewing studies from around the world found that mixing small amounts of water into diesel fuel can dramatically reduce harmful emissions, including nitrogen oxides and soot, while maintaining or even improving engine efficien
A colossal ancient collision may have left some of the Moon’s deepest secrets surprisingly close to future Artemis landing sites。 By recreating the impact that formed the giant South Pole-Aitken basin—the Moon’s largest and oldest crater—scientists found that a low-angle strike from a large, iron-cored object blasted material from deep inside the M
A hidden population of South African leopards has revealed a remarkable evolutionary story。 Researchers analyzing entire leopard genomes discovered that the Cape Floristic Region’s leopards are not only much smaller than most African leopards, but also genetically distinct after being isolated for roughly 20,000 years。 Surprisingly, despite their s
Scientists have uncovered new evidence that fireworks can pollute both the air and water in ways that extend beyond the visible smoke。 The findings show that leftover debris, fine particles, and airborne chemicals may affect ecosystems and increase people's exposure to air pollution during major celebrations
Scientists have uncovered a new explanation for what powers Yellowstone and other supervolcanoes。 Instead of a deep plume rising from near Earth’s core, a broad “mantle wind” may push hot rock beneath Yellowstone, generating magma closer to the surface。 This process helps create a massive underground magma network and may explain how supervolcanoes
Ancient asteroid impacts may have done more than reshape Earth's surface—they could have helped spark life itself。 New computer models show the collisions created enormous underground hydrothermal systems by cracking the planet's crust and allowing hot water to flow through it。 These long-lasting, life-friendly environments may have covered much of
A new sunlight-powered material can convert visible light into higher-energy UV light, overcoming a challenge that has frustrated scientists for years。 The breakthrough could enable cleaner air purification, solar-driven chemistry, and advanced manufacturing technologies using nothing more than natural sunlight
Two newly confirmed "super-puff" planets are so diffuse that they are less dense than cotton candy, despite being about the size of Jupiter。 Their rare orbital relationship and enormous, lightweight atmospheres could provide valuable clues about how some of the strangest planets in the galaxy come to exist
Texas win at 5th Circuit left in place as attempts to overturn age law continue
Engineers at a deep underground research facility noticed something strange during major rainstorms: airflow underground sometimes reversed direction。 Using new sensors and mathematical modeling, they found that water rushing down a shaft was effectively pushing air through the tunnels like a giant piston。 The breakthrough explains a long-standing
Scientists have combined machine learning with quantum physics to discover two new superconductors and create a much faster way to search for many more。 The technique could bring researchers significantly closer to the long-sought goal of a room-temperature superconductor
SETI scientists searched the interstellar object 3I/ATLAS for radio signals that could indicate extraterrestrial technology but found nothing beyond human-made interference。 Even so, the rapid-response observations helped confirm the object's natural origin and showcased how future interstellar visitors can be investigated for signs of intelligent
Male dragonflies' dramatic aerial combat maneuvers emerge from relatively simple vision-based rules
A new study suggests early humans were using fire in South Africa’s Wonderwerk Cave as far back as 1。79 million years ago。 Researchers found burned bones deep inside the cave, where natural wildfires could not have reached, indicating that fire was likely carried in and maintained by human ancestors
Astronomers may have witnessed one of the rarest and most dramatic cosmic events ever seen: a long-sought intermediate-mass black hole ripping apart a dense white dwarf star and devouring it。 The Einstein Probe space telescope caught the explosion in its earliest moments, revealing an unusual sequence of intense X-ray flashes unlike anything seen i
Astronomers have finally cracked the mystery of the famous “Pink Planet,” a strange world 57 light-years away that has puzzled scientists for more than a decade。 Using the James Webb Space Telescope, researchers discovered that its atmosphere contains water vapor, methane, carbon dioxide, ammonia, and something never directly confirmed before in su
Cases have risen quickly as officials are working to identify a common source
NASA's Hubble Space Telescope has captured a spectacular red, white, and blue view of one of the Milky Way's oldest star clusters to celebrate the nation's 250th anniversary。 Hidden within the ancient cluster are clues to how exploding stars helped transform the young universe into one capable of forming planets and, eventually, life