In an open environment, a consensus building means for maintaining dependability throughout the entire life cycle of a target system between stakeholders is provided, thereby appropriately operating the target system in accordance with the content of an agreement between the stakeholders. Also disclosed are fine fiber materials that can be made from the improved polymeric materials in the form of microfiber and nanofiber structures. A disturbance estimation observer outputs the result of estimation of disturbance to the adding unit. The set of one or more sink devices is presented to the user. The conical parts are made from molybdenum.