The laboratory experiments of TBM gauge cutters were carried out by using a linear rock cutting rig and a commercially available disc cutter. In the experiments two parameters were controlled principally to realize the configuration of gauge cutters: one is the angle of the disc plane against the axis of machine thrust α, and the other is the dip angle of the rock surface β. The experimental results provided some empirical formulae for predicting tool forces needed for gauge cutters to penetrate a rated depth. The formulae show that the tool force for gauge cutters would be intensified unless the plunge angle of the disc relative to the rock surface, α-β, remains positive. But also the formulae suggest that the tool force for gauge cutters could be restricted to that for face cutters when the relative plunge angle approaches to zero. Thus the formulae determined from the present investigation provide us a rational design criterion for alleviating tool force needed for TBM gauge cutters and prolonging their operational life-spans.

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In the first report, the relationship between a periodic motion of particles in a solid-liquid twophase flows and a swaying motion of a pipe was become clear experimentally. The virtual mass and the Basset term have a very important function for unsteady flows and micro dynamics of steady flows and it is necessary to prove the effects of these terms on particle motion. The solid-liquid two-phase flows in a swaying pipe is very suitable to do the above mentioned. This paper shows the effects on a particle motion of the flow by means of a high order numerical simulation. The main results are as follows:
1.The equation of motion for solid particles in a swaying pipe with consideration of virtual mass, the Basset term and unsteady frictional force between particles and pipe wall is derived.
2.The numerical method which can remove the trend on numerical solution originated by an inappropriate analysis for the Basset term is presented.
3.The numerical results by means of the model and the numerical method express the characteristics of the particles motion of the flow.
4.Virtual mass and the Basset term is needed to analyze time-series particles velocity of the flow and the differences between numerical solutions with consideration of these terms and ones without consideration those are clarified.
5.The effects of these terms on time-average velocity are negligible from the standpoint of technology.

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Several researches on the automation of LHD have been performed. Many of them are focused on the navigation, however, the scooping is one of the main function of LHD. The task planning function has to be included in the automatic scooping system. By the task planning, a detail of the bucket motion at each scooping is determined. For the effective task planning of scooping operation by LHD in mines, the adequate model of bucket motion is required.
In this paper, the bucket path model of scooping is proposed which is based on the motion measuring. The motion of scooping of a wheel loader at gravel plant is measured with the video camera and image processing system. The model bucket path comprises three sections. The cutting edge moves on horizontal, inclined and vertical straight line. The bucket path is determined by two parameters: the scooping depth and scooping angle. The kinematical analysis of the model is compared with the measuring result. The proposed model could be a standardized bucket path in the scooping task planning.

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Synthesis of neodymium sulfide from neodymium sulfate by carbon reduction was studied with the aim to develop a new sulfide production process which is technologically adoptable. Reduction of anhydrous neodymium sulfate Nd₂ (SO₄) ₃ by hydrogen was found not to be sufficient to form sesquisulfides Nd₂S₃, resulting in the formation of oxysulfide Nd₂O₂S. Neodymium sesquisulfide (γ-Nd₂S₃) was formed as a mixture with Nd₂O₂S when the anhydrous sulfate was heated with activated carbon in nitrogen over 1, 273 K. The monophasic α-Nd₂S₃ was obtained by the reduction with activated carbon in the presence of sulfur vapor over 1, 073 K. The formation of Nd₂S₃ by carbon reduction of Nd₂ (SO₄) ₃ was thermodynamically discussed. The lattice parameters of α-Nd₂S₃ were a=0.7444±0.0001, b=1.5519±0.0002, c=0.4028±0.0001nm which were in good agreelnent with the calculated and reported values. The Nd₂S₃ obtained by the similar way at 1, 273 K contained a smaller amount of impurities of carbon, nitrogen and/or oxygen compared with those obtained at 1, 073 K.

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A reliable method has been required for the estimation of mechanical properties of rock and for observation of the stability of rock-structure. In this study, drained creep tests under uniaxial compressive load were carried out with the aim of estimating the long-term stability of ‘Ohya-stone’(porous tuff, in Japan). In these experiments, axial and lateral strains were measured and Acous-tic Emission (AE) activities were monitored, at the same time. The loading times maintained in these creep tests varied between several minuets to one month.
Some general observations made are: 1) The creep stress in any case of failure must exceed 70% of the uniaxial compressive strength, which corresponds to the yielding stress of the rock. 2) The minimum value of volumetric strain for this rock type in creep process is nearly constant in each sample. 3) The relationship between the point of minimum strain rate and that elapsed time in log-log plotting becomes a straight line which slope is-1. 4) The strain rate in the secondary creep region is almost in constant and the creep time in this region occupies over 90% of entire test intervals. 5) Therefore, it has high possibility that failure of rock will occur when the amount of strain in creep region reaches a constant value in each sample. 6) The AE activity noted to develop during the creep process is more active only for a short period in the tertiary creep region. And, to apply AE monitoring for prediction of failure of rock-structure, the mechanism of AE activity information must be clarified in more detail.
Including the discussion of mechanism of AE activity in the secondary creep region, further experiments are to be conducted in our laboratory.
However, a practical method for estimating the long-term stability of rock below the yielding point load range of the rock, as a substitute for creep test, must be developed.

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In the fatigue tests of coals the changes in gas permeability and acoustic emission activity have been monitored in order to obtain an index of the occurrence of unclosing cracks. Actually at the final stage of fatigue fractures the acoustic emission activity occurred in the unloading process in the same manner as that in the loading process and the amplitude-frequency distribution of acoustic emissions changed from a simple straight line to three straight lines broken at two points. These facts proved that opening cracks in which some fragments were caught turned out to unclosing cracks. From the above monitored results, it became clear that the gas permeability of the unclosing cracks did not depend on the external stresses. Moreover, it was confirmed that the characteristic of the amplitude-frequency distribution of acoustic emissions was useful for judging the occurrence of unclosing cracks.

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Gaseous species in the plasma during deposition influence the amount of sp², sp³ site and hydrogen in hydrogenated amorphous carbon (a-C: H) films. Then the observation of plasma conditions were considered to be useful for a-C: H film deposition. The gaseous species were identified by optical emission spectroscopy (OES) using a spectral multichannel photodetector. And the effect of helium as an additive gas was also investigated by OES. The deposited a-C: H films were characterized by Fouriertransform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) to find the relationship with the results of OES.
The identified emission spectra were H_α, H_β and CH in plasma of methane.Emission spectra H_α, H_β, CH and C₂ were observed in the plasma of benzene and acetone, and the intensity ratio C₂/_α of acetone became higher than that of benzene.The decomposition of benzene was promoted owing to Penning effect of helium, as the results of OES and probe current measurement.On the other hand, Penning effect was not observed in the case of mixing methane or acetone with helium.
Sharp spectra of CH, CH₂sp³ bondings were found in a-C: H film deposited from methane. Spectra of CH_x bonds, however, were hardly observed in a-C: H films deposited from benzene and acetone. The CH was considered to be the main precursor of a-C: H film deposition from methane. Relatively strong emission spectra of C₂ appeared during deposition in plasma of benzene and acetone. It was suggested that the C₂ was the main precursor in the plasma of benzene or acetone, which corresponded to finding few C-H bonding in the a-C: H films obtained from benzene and acetone as asource. It was concluded that the results of FT-IR were in accord with the results of OES.
The results of XPS showed that a-C: H films deposited by ionization deposition method in the present work were extremely broad bonding and amorphous situation in comparison with diamond, graphite, polyethylene, glassy carbon and a-C: H film deposited by RF CVD.

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Transmission and dissipation of stress wave at a percussive-drill rod-joint of the coupling sleeve type were determined at three sleeve-preload levels. The experimental results show that a tension wave is reflected from a sleeve, following the compression incident wave. An amplitude of reflected wave decreases with sleeve-preload. These observed results indicate that the ends of rods coupled by the sleeve do not contact perfectly each other.
A simple model (model 1) is proposed which consists of two rods and a spring connecting two rods. The spring k₁₂ with a finite spring constant represents rigidity between two rod ends. Selecting an appropriate value for a spring constant, good agreement is obtained between numerical and experimental results.
Model 2 is also proposed which is characterized by a spring k₁₂, the mass for sleeve and two additional springs representing the rigidity between rod and sleeve. The model 2 is an improved version of model 1 and very good agreement is obtained in case of transmission of compression wave.

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The manganese dioxide prepared by ozone oxidation in acidified solutions of MnSO₄ at different temperatures (OMD) was characterized by thermal analysis (DTA and TGA). The changes detected in the thermal analysis were further investigated by X-ray diffraction and oxidation capacity measurement through oxalate-reduction for the OMD samples heat-treated at various temperatures. The discharge behavior was also determined for the heat-treated OMD samples.
The ozone oxidation conditions, temperature and sulfuric acid concentration, remarkably affect the changes appearing in thermal analysis due to the crystal transformation of MnO₂ from γ-or α-type to β-type and the first thermal decomposition of MnO₂ to Mn₂O₃ as well as due to the liberation of the water in a temperature range below 200°C.
The oxidation capacity of OMD sample, expressed in MnO2 equivalent, was observed to decrease in duration of heat treatment, more pronouncedly for OMD precipitated at higher acid concentration and low temperature.
Discharge characteristics of OMD were significantly changed by heating for 2 hours at temperatures lower than 200°C. The heat treatment at around 100°C improved the discharge behavior of OMD prepared at 60 to 80°C and acid concentration up to 1.0 M, the discharge capacity being comparable to or better than that of EMD. The OMD samples heated to above 150°C showed poor discharge behavior.
It is suggested that the crystal lattice space and activity as an oxide of OMD are changed in close corelation with water liberation during heating at fairly low temperatures.

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