A historical review of the mining industry in Japan illustrates the important contribution that mining has made to human civilization. In ancient Japan, as in ancient China or Europe, the function of mining in shaping society was as crucial as the role played by agriculture. The discovery and extraction of metals from the Earth, led to innovation in technologies to make use of these metals and prompted the development of civilization itself. Control of the mines was linked to political power, as well as civil cultures, and with so many people depending upon mining for their livelihoods, it has even been claimed, "The history of mining, is the history of civilization." Naturally, the virtual cessation of domestic mining has severely affected the Japanese Mining Industry. However, history shows that the mining industry has had a hard voyage so far, and it has been tossed around on the waves of good and bad times. Today's difficulty is nothing more than one of these troughs. Internationalization of the economic climate and an increased awareness of environmental concerns, together with rapid advances in mechatronics and other associated fields have already started to propel the mining industry back up onto the highest of those waves. In addition to this, the implementation of a clear national policy and an effective strategy to secure the supply of mineral resources will give the mining industry a new lease of life for unlimited growth, as it evolves to meet the demands of the 21st Century.

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The GPS displacement monitoring system has been developed by the authors to assess the stability of large slopes. In order to provide more accurate measurement results, a stochastic smoothing method (the trend model) is applied to displacements measured by the system in this paper. Five types of displacement behavior are supposed as the monitoring results; i. e., 1)static stable state, 2)step displacement, 3)steady rate displacement, 4)converging creep, and 5)tertiary creep. Numerical simulations are conducted for the above displacement behavior types using data measured at a limestone quarry to investigate the applicability of the trend model. It is shown that the trend model can improve the accuracy of the measurement results through those simulations.

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In this study, solid-liquid flows with coarse particles, which form a highly concentrated zone in a pipe, were simulated. In general, the cell size of the continuous phase is larger than the particle size. However, with increases in particle size, the cell size must be close to the particle size in order to maintain high resolution of the fluid velocity. Simulation using equal cell and particle sizes was carried out to investigate the effects of fluid velocity, pressure gradient and void fraction on the settling motion of a particle in rest water. For simulating a particle cloud, a conventional Lagrangian/Eulerian method using the drag coefficient of a particle cloud was employed. The results so obtained were compared with the results using the drag coefficient of a single particle under the same flow and particle conditions.

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When analyzing the lateral vibration of an offshore structure supported by seabed layer, the effect of this layer must be taken into consideration. In the third report, a method has been proposed for reducing a four-leg offshore structure supported by seabed layer to a one-leg structure, and its natural frequency of lateral vibration has been analyzed theoretically. Furthermore, the validity of this method has been clarified by the model experiment. In this paper, the wave-induced resonance amplitude as well as bending stress in the leg of the offshore structure were analyzed theoretically and simulated numerically. The main results obtained are as follows : (1) With respect to the off-shore structure considered in this study, the first resonance of lateral vibration could be induced in it by practical wave-excitations. Once the resonance occurs, the leg's amplitude of the structure will increase almost linearly as the time elapses. (2) The maximum bending stress caused by the first-mode of lateral vibration always occurs at the top of the leg. (3) As soon as the vibration is fallen into the resonant state, the maximum bending stress in the leg increases almost linearly with the time, and then reaches the yield strength of the leg material in about 50 seconds, causing the failure of the structure. (4) Based upon the above results, the criteria for designing offshore structures are proposed from the viewpoint of evading the resonance phenomena caused by surface waves.

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It is anticipated that a response of flow rates of lifting water and solid to a change of supplied air becomes complicated especially in a large-scale air-lift pump. Then it is inevitable to grasp unsteady flow in air-lift pumps for lifting solid in consideration of pipe blockage. In this work, a numerical method of unsteady flow was developed; discretized equations were derived by integration of the governing equations based on the drift flux model for gas-liquid-solid three-phase flow over the control volume, and numerical analyses were accomplished using the numerical procedure based on the so-called SIMPLER algorithm. To verify the present method, numerical results were compared with experimental results, which had been obtained with the air-lift system of 200 m depth. The present results show reasonable agreement with the experimental data. Hence the present method can be applicable to an examination of safety operation of air-lift systems.

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The authors have developed a new method to evaluate coal flotation behavior. The liberation degree of mineral matter in feed and the ultimate ash content of froth product can be estimated using this method. Modified release analysis and oil agglomeration tests were carried out using different feed size of coal. The results were plotted on combustible recovery vs. ash content of clean coal curves and on combustible (or mineral matter) recovery vs. yield curves. Graphic analysis of these curves is proposed to give the ultimate ash content of coal concentrate obtained under ideal conditions and the liberation degree of mineral matter of flotation feed. By comparing these curves with conventional flotation results, the mass of mineral matter entrapped mechanically in froth was determined. In this paper the above procedures are described in detail using Datong coal. The ultimate ash content decreased and reached about 1 % with decreasing average feed sizes, smaller than 2μm, and the liberation degree increased to above 90 %. The mass of entrapped mineral matter increased drastically for feed smaller than 20μm.

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Dispersion of magnetic iron oxide powder, γ-Fe2O3 in the mixture of toluene and cyclohexane was studied to decrease the viscosity of the slurry and prepare the stable slurry in the presence of some saturated fatty acids with a straight chain as dispersing agents. The dispersion of γ-Fe2O3 is controlled by the steric hindrance of the dispersing agent adsorbed on it. Therefore, the viscosity and dispersion of the slurry significantly depend on the carbon number and the amount of the fatty acids. Since water content of γ-Fe2O3 greatly influences the control of the viscosity and dispersion degree, low water content is required to get lower viscosity and more stable dispersed state. The four measurements to evaluate slurry flow characteristics, namely viscosity, yield stress, sedimentation volume and particle size measurements, can become a standard method to estimate the degree of flocculation and dispersion of particles in solvents.

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The demand of poultry meats, especially broiler, should be increased toward 21st century as one of the most promising protein resources. The production of broiler is accompanied with large amounts of waste feathers. We have focused attention on the extraction of proteins from waste feathers and a simple extraction process has been developed. The extracted protein liquid indicates a strong foamability, which should be useful as a raw light material to be mixed with a solid raw material to produce a low density material. The foaming characteristics have been experimentally evaluated and ferric sulphate has been confirmed to reinforce and stabilise generated protein foams. The optimal additions of ferric sulphate and the protein liquid have also been decided by observing the drainage rate of liquid from generated foam films. To demonstrate the capability of protein foams to produce low density materials bubble cement and bubble mortar have been evaluated in terms of the mouldability, bubble dispersibility and compressive strength. The mouldability and the homogeneous dispersion of bubbles in a moulded material have been guaranteed even when the bubble volume fraction exceeds 0.5. We regard this demonstration as a convincing evidence of the capability of protein foams as a light raw material to be mixed with a solid raw material in producing a low density material with high performances in heat, sound and water protection.

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Thin films were prepared by r. f. sputtering using 21 kinds of oxides as target. The molar deposition rate and morphology of sputtered oxide films were measured on the basis of SEM and XRD. The factors which decided the molar deposition rate of sputtered oxide films were discussed in terms of the momentum transfer process, the thermal evaporation process, and the crystal structure of oxide. As a result, we classified the oxides in (？) Coulomb's force (binding energy) dependence type, (？) vapor pressure dependence type, and (？) Madelung constant dominant type. We classified the morphology of sputtered thin films in (？) amorphous-, (？) amorphous + crystal-, and (？) crystal-non-decomposition type, and (？) amorphous-, (？) crystal-, and (？) crystal + sub oxide formation-decomposition type.

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