Abduction is a form of inference that seeks the best explanation for the given observation. Because it provides a reasoning process based on background knowledge, it is used in applications that need convincing explanations. In this study, we consider weighted abduction, which is one of the commonly used mathematical models for abduction. The main difficulty associated with applying weighted abduction to real problems is its computational complexity. A state-of-the-art method formulates weighted abduction as an integer linear programming (ILP) problem and solves it using efficient ILP solvers; however, it is still limited to solving problems that include at most 100 rules of background knowledge and observations.

Japan's hot startup stocks have two things in common: They do business in areas that could be described as mundane, and they've pushed their founders into the league of the ultrawealthy. Take AI Inside Inc., which helps turn handwritten documents into electronic files. Or Rakus Co., whose goal is to help small and midsize enterprises with their bookkeeping and emailing services. Their shares have all more than doubled in the past year, enriching their founders and leading to talk of a burgeoning tech scene that's very different from Silicon Valley. While the companies are using technologies like artificial intelligence and cloud computing, they're applying them in less sexy ways.

Last August, Masahide Sasaki and his team instructed a satellite to shoot laser beams at a suburb of Tokyo. The laser beam, made of infrared light, was invisible to the human eye. By the time it had traveled through hundreds of miles of outer space and atmosphere, the light was harmless: It had spread out like a spotlight, about as wide as 10 soccer fields. Some of that light made its way into the end of a telescope, where it bounced off mirrors and flew through lenses and filters onto a photon-measuring detector. Someday, Sasaki hopes, that light could be more than invisible wavelengths hitting a telescope--it could be encoded with information.

Creativity is alive and well at Samsung, which is developing several cool devices in its labs, including a home companion robot called Otto. The multi-talented robot can answer questions and double as a part-time security system when needed. It is expected to be demonstrated at the Samsung Developer Conference this week in San Francisco. Functionally, Otto is similar in some ways to Amazon Echo, featuring an interactive speaker that can answer questions, order products and play music. But the robot also includes a "head" that hosts a high-definition camera and a display.