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This report describes a case where counterweight fill using a high-intensity geotextile is applied as a measure to prevent landslide. In addition, this report shows the strain acting on the reinforcing material during and after construction, the earth pressure gauge installed in the embankment, and the field measurement results of the surface-wave method. From a series of observation results, no strain acting on the geotextiles was confirmed, nor was there any abnormality in the reinforced embankment. Furthermore, no local decrease in the S-wave velocity could be confirmed, and no change in the internal state of the reinforced embankment could be confirmed.

This paper will discuss the large scale control system and concentrate attention on the system structure and system design philosophy, with reference to the overall control system of Nippon Steel Yawata Hot Strip Mill. This is one of the most recent and advanced hot strip mill installations, of which requirements on the control system were 1) Large scale process data handling 2) Plant operation based on complex mathematical model 3) Revolutional expansion of digital control and so on. To respond to these requirements, the physical system structure is composed of four SCC computers, five DDC computers, nine FEPs (Front-End Processor) and thirty PCs (Programmable Controller). The four loops of data-way are also involved for the data communication among the processors. The specific features of this control system, are that the total system is designed to be divided into three levels, say SCC level (with FEPs), DDC 1 level (DDC by computer) and DDC 2 level (DDC by PCs), and that one of the data-way loops, SCC data-way, is assigned for process-information data-base and the other data-way, DDC data-way, for process control data-base. The most fundamental design philosophy, the main theme of this article, is “Load distribution and resource sharing”, and the following items will be discussed in detail: 1) Three level hierarchy control system philosophy. 2) Coupling and optimal load sharing among SCC computers and among DDC computers as well. 3) Load distribution of SCC computers to FEPs. 4) Sharing of process input/output gears and/or other devices and equipment, among computers and PCs.