In order to correct a warp of social structure due to the Japanese policy centering around Tokyo up to the present, the national land development in the 21st century should be balanced within all of Japan and therefore the coexistence and growth together with the development and environmental protection should be necessary to create the regional area which will be rich and active. An author's opinion on the regional development is duscussed.
The demand of grinding stone as an important construction material is now increasing. But, the grinding stone industry taking the duty of its supply is disliked by its neighbourhood and becomes gradually difficalt to work, because this industry may bring the distruction of nature and environmental pollution.
Nowadays, the industry must wipe off this unfavorable criticism and must transform itself into the contributor for the regional area. An auther's propose is stated toward improvements of the grinding stone industry.

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Although crushed stone is indispensable to building and maintenance of social infrastructure and a large amount of it (about 9.5×10⁸t, in Japan 1990) has been used, few papers have studied crushed stone resources because of their abundance. In Japan, nevertheless, maintaining a stable supply against the increasing demand will become a serious problem. There are many problems in mining crushed stone and these can be classified as economic and social restrictions. Economic restrictions arise mainly from increases in both labor and transportation costs. Social restrictions include many environmental protection regulations by national and local authorities.
In this paper, problems concerning crushed stone resources are classified as a part of geoscience and their deposits, demand and supply are considered. Efforts that should be made in the future to increase the potential of the quarrying business can be arranged into three categories, that is, automated methods of planning the mine site, efficient systems of transportation from factory to consumer, effective measures to deal with spoiled sight.

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Many king of jaw crusheres have been developed and are used as primary crushers aggregate crusing plants at present. Therefore these crushers have influenced on plant operation and product cost and so on.
In order to develop the new jaw crusher, the new design method should be established based on the combination of rock mechanics and mechanical engineering. In other word, it is required to establish the design method based on not only the experiential knowledge but also the theoretical analysis.
In this report, a new design method of jaw crusher is proposed and the new jaw crusher named “ASTROJAW” developed by this method is introduced.

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