Abstract: Embodiments of the present disclosure provide a method and an Internet of Things (IoT) system for managing smart gas safety based on user activity. The method includes obtaining gas data of a gas user, determining, based on the gas data, a gas risk for the gas user, and determining at least one target on-site user based on the gas risk. The method further includes determining, based on at least the gas data of the target on-site user, an activity distribution of the at least one target on-site user, and based on the activity distribution, determining a recommended on-site time set and sending the recommended on-site time set to the at least one target on-site user.

Abstract: A method, an Internet of Things system, and a storage medium for assessing a smart gas emergency plan are provided, the method is executed by a smart gas safety management platform of the Internet of Things system. The method may include: obtaining a gas pipeline network warning information distribution of a gas pipeline network, the warning information distribution including warning information of at least one warning point location; obtaining gas monitoring data of at least one associated point location corresponding to the at least one warning point location; determining at least one emergency processing point based on the warning information distribution and the gas monitoring data of at least one associated point location; and determining a deployment plan for a gas emergency vehicle based on a gas supply blockage range of the at least one emergency processing point.

Abstract: To achieve high-power single transverse mode laser, we here propose a supersymmetry (SUSY)-based triple-ridge waveguide semiconductor laser structure, which is composed of an electrically pumped main broad-ridge waveguide located in the middle and a pair of lossy auxiliary partner waveguides. The auxiliary partner waveguides are designed to provide dissipative modes that can phase match and couple with the higher-order modes in the main waveguide. By appropriately manipulating the gain-loss discrimination of the modes in the laser cavity, one can effectively suppress all the undesired higher-order transverse modes while keeping the fundamental one almost unaffected, thereby ensuring stable single-mode operation with a larger emitting aperture and accordingly a higher output power than a conventional single-transverse-mode ridge waveguide diode laser.