In recent years, the Asia/Pacific region, above all Asia, has achieved a remarkable economic growth, and played the role of a growth center in the world. Given Asia's vast areas and huge populations, a higher economic growth should have a massive impact on its total energy demand. However, Asia's energy resources are by far smaller than the world's average in either current production or per-population reserves terms. The emerging economies in Asia require the stable supply of energy kept flowing from outside the region for the sustainable development. What's sending Asia's energy demand up is the strong demand for the secondary energy such as electricity and petroleum products. Judging from greater domination of electricity, rural electrification, and advancing motorization in the years to come, the strong demand is likely to become stronger. Particularly, to better meet the high electricity growth, huge projects are planned for power development and transmission/distribution grid construction. The problem is whether the international community can fully afford necessary funds for such projects. Asian factors, like heavy coal dependence in meeting its primary energy demand and enormous populations, are causing many subjects to be solved, not to mention air pollution but acid rain now spreading region-wide and global environmental problem.

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Classification of geoscience data is an important tool for exploration of natural resources and interpretation of geophysical prospecting data. The minimum Euclidean distance method (MED) and the maximum likelihood method (ML) are typical methods in the supervised classification. These methods require that the boundary shape between two groups is linear and the frequency distribution of attribute data in each group is approximated by the multi-dimensional Gaussian distribution. A neural network (NN) can also be used in the classification and does not require the above conditions. The high accuracy of classification by NN over MED and ML was demonstrated in this paper using the three simple models with different shapes of group boundary. NN was applied to the classification of color image of excavated faces in the epithermal gold deposit in southwest Japan. In this mine, the ore grade is generally related to the vein's color, e. g., the white zone is rich in gold and silver, whereas the brown zone being strongly altered is low grade zone. Training samples were selected automatically through the self-organizing feature map. Using these training samples and the NN of multi-perceptron type, the color images of veins were classified into three parts：high, middle and low grade parts. Because the classification results were revealed to be appropriate by the comparison with the maps created by geologists, the effectiveness of NN for the classification of complicated data with several attributes was proved.

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For the rock engineering projects, it is necessary to correctly estimate the mechanical properties of the rock, namely, the stress-strain relations and strength properties, the time-dependent deformation properties and so on. In our previous studies, the drained creep tests under uni-axial compressive load were carried out on some soft rocks in Japan, such as Ohya-Ishi and Kimachi-sandstone. In these experiments, the axial and lateral strains and the acoustic emission activity were observed in the loading time intervals of several minutes ∼ one month. Also, the thin sections for microscope examination conducted on the specimens, which had loaded during the prescribed time or until some region of the creep process. In this study, the creep process and mechanism were discussed by using these experimental data, and the relationship between the failure process of creep loading and conventional uni-axial loading of rock were discussed by the specially planned testing programs of the experiment.by these results, it can be said that the residual compressive strength of the creep loaded rock specimen is almost the same as that of the intact rock, when the axial strain rate is in the decreasing condition, but the residual strength decreases the value when the axial strain rate passes the minimum value and in the increasing condition. Consequently, the failure process of the creep and conventional uni-axial loading are closely connected with each others；the changing point of the residual strength of the creep loaded rock which coincides to the minimum point of the axial strain rate, corresponds to the strength failure point of the rock under the conventional uni-axial compressive loading.

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A linear equation between axial strain, circumferential strain and axial stress was found while performing compression tests on several kinds of rock. This equation means that in such laboratory tests the trace of axial strain, circumferential strain and axial stress is located on a plane in the three-dimensional space defined by these quantities. New constitutive equations were derived combining the above-mentioned equation with another equation which derived assuming that the stiffness in the radial direction decreases with radial expansion. Using the set of the newly-deduced constitutive equations, the effect of confining pressure on strength and strain-softening behavior including Class？ can be simulated. Numerical results also show the decrease in radial stiffness due to crack existence.

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At the deeper coal mines in Hokkaido, Japan, the coal of working faces became hard frequently prior to coal outbursts and the gas concentration decreased unusually. In order to make clear the above phenomena the effects of temperature on strain hardening and gas permeability of stressed coal were investigated experimentally and theoretically in this study. Practically, the applicability of WLF equation to the effects of temperature and stress on creep strain rate were considered on the basis of the results of creep tests of confined coal. From this consideration it was proved that the reducibility existed between the effect of temperature and that of stress. Furthermore, creep strain and gas permeability of coal were expressed as a function of the effective stress compensated by adding the reduced stress of the effect of temperature to the applied stress. As these results, creep strain and gas permeability of coal increased and decreased rapidly under the depth of 500 m. The effects of earth temperature on strain hardening and gas permeability of stressed coal gave a reasonable explanation to the reason of frequent occurrence of coal outbursts at the mining of deep level coal seams.

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First, this paper describes the overview of the data relevant to the mine ventilation such as the total volume of ventilation air, the number of fans, the size of ventilation network, etc. and the procedures of calculation of the airflow distribution which are actually employed in various mines. Then statistical analysis of the ventilation networks are given. As a result it is found that too small friction factors or too small ventilation resistances are being used in almost all network analyses. This may be one of the major reasons for the inaccuracy of the ventilation network analyses and therefore particular attention should be given to the fact when ventilation network data are compiled. The calculation time required for an airflow distribution analysis depends not only on the method of calculation for a node pressure but also on the method how to consider a fan characteristics. The paper also describes the new method for the calculation of the airflow rate by the fan, which enhances the calculation speed and the stability of the analysis. Finally, an improved node potential method for calculating the pressure of two nodes at both ends of an airway simultaneously is proposed. The calculation time is reduced to 55 % on the average through these improvements.

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It is known that the typical control system based on BE electric power, which has been applied in many cement grinding plants, has some problems. Other types of controls therefore have recently been proposed. They require both to stabilize the process and to improve the product quality against the changes in clinker grindabilty. The authors have already constructed the transfer function model from population balances of the process. The purpose of this paper is to present an optimal control strategy based on the steady-state characteristics. Firstly we criticized several conventional control methods. For instance, it was quantitatively confirmed that the BE electric power control system could not regulate the product property and the multivariable one by manipulating the classifier cut size could not keep the product quality as well as its quantity simultaneously against the feed change in grindabilty. Consequently we have proposed a hierarchy control system, consisting of the two stages. The higher one is to determine the product set-point values and the lower one is to control the stability and the product quality. In this system, when the grindability becomes low the decrease of the product quantity can be prevented by changing the set point of the product quality. This system has also an advantage of avoiding the mill choking. As to the detection of gindability it was suggested to estimate it by measuring the product quantity and quality (specific surface) simultaneously, or practically mill discharge quality only.

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Cobalt crusts were leached in an ammoniacal solution using sulfur dioxide gas as a reductant, and the effects of leaching time, leaching temperature and concentration of ammonium carbonate on the leaching of nickel, cobalt, copper, iron and manganese were investigated. The selective leaching of nickel, cobalt and copper from cobalt crusts was attained by using ammonium carbonate solution and sulfur dioxide gas as a reductant. The leaching percentages of metallic elements under the suitable leaching conditions were 90 % for nickel, 97 % for cobalt, 93 % for copper, 1.8 % for iron and 6.0 % for manganese. The separation of nickel, cobalt, copper from ammonium carbonate solution was carried out by solvent extraction. Extraction experiment was done by using LIX84-I as extractant. The extraction percentages of copper and nickel were more than 99 %, while that of cobalt was less than 1.0 %. Extraction of cobalt was masked by sulfite ion. From the organic phase containing nickel and copper, nickel was selectively stripped by dilute sulfuric acid or hydrochloric acid solution at the pH of 1.5. Copper was stripped at the pH of zero.

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Recent popularization of portable electronics-instruments such as cordless telephone has been supported by research and development of the secondary battery such as lithium ion type, on which researches have been focusing so far to obtain the small size, the high discharge capacity, the high energy dencity, as well as the enviromental safty. This paper describes effective methods on oxidationγreduction potentials and other optimum conditons for the metal leaching with sulfurous acid from the sea manganese nodules, the oxidation/separation for iron with air/ozone from the leach solution, the selective separation of copper with hydrogen sulfide from the leach solution, and the oxidationγseparation for manganese dioxide with oxigen/ozone. The manganese dioxide obtained is identified to be the same material as electrolytic γ‐MnO2 used for batteries.

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