Average Co-Inventor Count = 2.67
ph-index = 2
The patent ph-index is calculated by counting the number of publications for which an author has been cited by other authors at least that same number of times.
Company Filing History:
1. Hitachi, Ltd. (2 from 42,508 patents)
2. Hitachi Engineering Co., Ltd. (2 from 162 patents)
2 patents:
1. 4653276 - Automatic control system for thermal power plant
2. 4577270 - Plant control method