Abstract: A method including: manufacturing a standard transmission object; simulating a transmission measurement process using simulation calculation method, to establish a database with respect to a transmission thickness, an equivalent water density, an original reconstruction density of the standard transmission object, a space angle cosine of the transmission source and an energy of a ? ray, fitting a corresponding relationship of the space angle cosine of the transmission source with respect to parameters of the standard transmission object and the energy of the ? ray based on the database; selecting a corresponding standard transmission object for transmission measurement for a transmission source to be characterized, to obtain an original reconstruction density of the standard transmission object; reading the space angle cosine of the transmission source to be characterized from the database according to fitted corresponding relationship of known parameters of the standard transmission object and the energy of

Abstract: A system and a method of black start for a combined operation of wind power, photovoltaic power, energy storage, and thermal power includes a renewable energy alternating current microgrid module, a power transmission and distribution module, and a thermal power generation module, the power transmission and distribution module is coupled to the renewable energy alternating current microgrid module and the thermal power generation module respectively. The renewable energy alternating current microgrid module includes a photovoltaic unit, a wind power unit, and an energy storage unit. The power transmission and distribution module is configured to transmit the electrical energy generated by the renewable energy alternating current microgrid module to the thermal power generation module. The thermal power generation module is configured to start an auxiliary equipment using the electrical energy transmitted by the power transmission and distribution module.

Abstract: The system for frequency modulation based on Direct Current (DC) controllable load for a high-voltage plant includes a frequency modulator and a DC-controllable load for the high-voltage plant connected to the frequency modulator. The frequency modulator includes a centralized rectifier configured to adjust power of loads in the DC-controllable load in response to a frequency modulation command. The DC-controllable load is configured to respond to an adjustment of the power of loads performed by the centralized rectifier.

Abstract: In some examples, a system may configured to execute the instructions to, based on the modular data of a peg modular, the item data and the draw strategy data, implement a set of modular placement optimization operations that generate a first modular dataset. In some examples, the set of modular placement optimization operations includes, determining, from a group of items, a combination of items to place onto the peg modular and, for each item of the combination of items, a placement position on the peg modular, and a number of facings. Moreover, the set of modular placement optimization operations includes generating the first modular dataset. Further, the system may be configured to execute the instructions to, based at least on the modular data the first modular dataset, implement a set of operations that determine whether to add additional facings.