Abstract: To provide a positioning technology capable of measuring a position of a moving object moving at high speed with high reliability, high accuracy, and high speed. The positioning system 1000 can obtain accurate position data using the positioning information collected from a plurality of base stations, and deliver the obtained accurate position data to the base station. In the positioning system 1000, the base station serving as the position reference station can always hold the accurate position data based on the accurate measurement result data. In the positioning system 1000, the base station whose accurate position is known is used as a position reference station to perform RTK positioning with, for example, the mobile station, thus allowing the position of the mobile station to be measured with high accuracy.

Abstract: A developing device for developing an electrostatic latent image formed on an image carrier includes a roller which carries toner particles to the developing position and a porous foam member of a material such as urethane resin which contacts the roller. The porous foam member comes in contact with either a developing roller or a toner supply roller which supplies toner particles to the developing roller. Toner particles supported in the holes of the porous foam member are charged as the particles rub against the developing roller or toner supply roller, causing the particles to be readily transferred to the roller. The porous foam member causes the amount of toner particles supported on the surface of the developing roller or the toner-supply roller to be sufficient to prevent a reduction in the density of the toner image even directly after a larger amount of toner particles are consumed for developing a solid toner region for example.

Abstract: A developing apparatus for developing a charged latent image formed on a photosensitive drum with a developer including toners and carriers comprises a casing for holding the developer, a developing roller for carrying the developer supplied from the casing, and conveying the developer from the casing to the photosensitive drum so as to develop the charged latent image formed on the photosensitive drum with the developer, a doctor blade for controlling the thickness of the developer carried on the developiung roller to a predetermined value, a scraper for removing the developer which keeps on being carried on the developing roller after the end of developing operation, and returning the removed developer into the casing, and a toner removing member for removing toners, directly attached on the developing roller, from the developing roller, the toner removing member being provided independent of the developer removing scraper.