To elucidate the paradigm of modern materials civilization, typical materials civilizations keeping the coexistence of human culture with natural system from pre-modern times and typical technologies characterizing modern materials civilization are taken notice.
The paradigms of the typical materials civilizations and the typical technologies are fundamentally discussed by use of structuralism analysis method. And their structuralism structures are respectively and qualitatively elucidated by the analysis mentioned above.The characterizations of these structures are described by structuralism structure diagram.
As a result, the following conclusions are obtained.
1) The paradigms of typical materials civilizations keeping the coexistence of human culture with natural system are described by the structuralism structure balancing between two mutually contradictory transformation structures.
2) The paradigm of pillage between two mutually different civilizations or civilization and natural system forms single irreversible physics or meta-physics transformation structure (natural system to culture, civilization to another one).
3) The paradigm of each typical technology characterizing modern materials civilization contains a negative irreversible meta-physics transformation structure introducing negative accumulation into civilization. In particular, technologies such as car, computer, atomic power generation, and genetic engineering produce the paradigm including unstable, austismic, threatening or fearful phase.

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The precursor of Co and Pr added zinc oxide varistor was successfully obtained. by a wet chemical method using zinc acetate as a starting material with praseod ymium oxide and cobalt chloride as additives.Changes in crystalline size, compact density, additives distribution, and voltage-current curve were characterized with sintering temperatures from 1200 to 1300°C for the samples prepared by the wet chemical method with or without calcination, and by a ball-mill method for a comparison.
The crystalline size of zinc oxide increased for each sample with the increase in sintering temperature.The distribution is narrower and the average crystalline size is smaller for a sample by a wet chemical method. Cobalt contributed to almost constant value of coefficient of variation for the samples prepared by the wet chemical method in this temperature range.Large value of coefficient of variation was obtained for praseodymium at high temperature, which resulted from segregation to grain boundaries with growth of crystalline. Decreasing tendency was observed of nonlinearity α and break-down voltage with the increase in sintering temperature. Smaller amount of addition of both Co and Pr in the samples prepared by the wet chemical method was effective for improving the varistor characteristics.

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This paper proposes a theoretical model in the predication of high-temperature creep rate of precipitation-hardening alloy. Theoretical calculations were carried out of the high-temperature creep rate to four types of aluminum alloy states: stable dispersion particles (P), precipitation-particles with solubilizing (Pd), with solubilizing and coarsening particles (Pdc) and pure matrix metal (M) by means of this model. The effects of temperature ranging from 0.58Tm to 0.70Tm (Tm: the absolute melting point of the matrix metal) and stress ranging from 3.5×10^-4E to 1.0×10^-2E (E: the Young's modulus of the matrix metal) on creep rate were examined in these alloy states. The influence of solubilizing and coarsening of particles on creep behaviours is significant in precipitation-hardening alloy.

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The effect of MgO addition on the microstructure and the electronic properties of the SrTiO₃-based varistor have been investigated. The addition of MgO on the calcined powder contributed to an increase in nonlinear coefficient (α). The MgO promoted grain growth in sintering process. After sintering, MgO existed at the grain boundary and effected on the oxygen diffusion. The capaci tance of the grain and the grain boundary was decreased by the addition of MgO. As the result, the height of Schottkey barrier increased with the addition of MgO.
We thought that the increase of nonlinear coefficient (α) was the result of inrrpnsp in hpight nf Schottky barrier.

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Development of the linear inhomogeneous layer element LILE, orients specially to a numerical computation of elastic wave backsctter from a gradient inhomogeneous layered masterial. The stacking of LILE provides us an excellent model for the material. Reflectance curves developed as a function of the incident wave number are presented in a wide frequency range, and discussed on the relation between layered structures of a composite and the backsctter intensity. The results show that number of peaks coming up in the curves informs us the detail of layering structure.

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Graft copolymers of methyl acrylate-g-(2-vinylpyridinium bromide-co-vinylalcohol) were prepared by the reaction of (2-vinylpyridinium bromide-co-vinylalcohol) with methyl acrylate. The flocculating abilities for 5% aqueous kaolin suspension were investigated in the reiation to the structures by measuring the sedimentation rate, the sedimentation volume, and the turbidity. The results obtained are as follows. 1) For every graft copolymer, the optimum copolymer concentration required to flocculate 5% kaolin suspension was 6-50ppm, and under these conditions, the electrophoretic mobility of kaolin was relatively small. 2) Suitable mole fraction of vinylalcohol (F_VA) and that of ionization group (F_I2VP) in copolymer were 0.15 and 0.25 respectively. 3) Flocculating action increased with increase of mole fraction of methyl acrylate (F_MA) in copolymer. 4) Flocculating ability of each copolymer increased with increasing inherent viscosity. 5) Suitable pH values for the flocculating action were in the range of about 2-12. 6) An isoelectric point was found in the vicin ity of pH 4 and optimum flocculating ability was observed in the pH range of 4-10. 7) Copolymers were more effective for typical commercial flocculants such as Sumifioc-FC, PAS-A, and Himoloc Neo 600.

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In recent years, oil hydraulic spool valves have been widely used in electricmechanical control systems. However, the steady axial flow forces in the oil hydraulic spool valves are produced by the internal oil flow, and control of oil hydraulic spool valves becomes difficult owing to the effect of the steady axial flow forces.
In this paper, whole domain of fluid inside a spool valve is simulated by the boundary element method.Shapes of sleeves are modified, and steady axial flow forces, flow patterns and boundary pressure distribution are calculated and compared. It is found that when a sleeve takes a shape shown in Fig.6, the steady axial flow forces applied on the spool are greatly decreased, and the angle θ_n of injection fluid at jet orifice also increases due to coanda effect of the flow.

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Stress corrosion cracking of SUS310S steel single crystals with ‹100›, ‹110› and ‹111› growth directions has been potentiostatically examined on crystallography of the fractured surface in 35% MgCl₂ solution at 80°C. The useful results have been surmarized as follows:
(1) Anodic current density in polarization curve exponentially increased with potential without the occurrence of apparent active, passive and pitting regions.
(2) Time to fracture exponentially decreased with the increase of potential above corrosion potential.
(3) Macroscopically determined crystallographic orientations by trace analysis were located within 10° of latitude from {100} to {110}.
(4) Microscopically determined crystallographic orientations by inclination method were also located within 10° of latitude from {100} to {110}.

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Recently, robotics has been receiving considerable attention in many fields, especially in mining, civil engineering and construction field because the working environment in these fields is severe for workers to work. However, it is very difficult to apply the robots or autonomous machines to these fields because the working environment changes according to the advance of the work. Therefore, robots should have an ability to understand the change of the working environment and to work autonomously.
The purpose of this study is to investigate the vision system for understanding the piled fragment rocks by using a laser slit and an image. In this study, the method to judge the existence of the piled rock was proposed by using the laser slit and image. Furthermore, the pattern of images was recognized by use of the template which was obtained in the preliminary experiment. Through this experiment, it was confirmed that this vision system worked well.

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Comminution is the oldest mechanical unit operation for size reduction of solid materials and an important step in many processes by which raw materials are converted into intermediate or final products. The purposes for which solid materials comminuted are to reduce the size, to increase the surface area and to free the useful materials from its matrices. Recentry, to modify the surface of solids, to prepare the composite materials, to examine the mechanical alloying and to control the particle shape are involved in its purpose. A demand for fine or ultrafine particles is also incresing in many kinds of industries. The energy efficiency of comminution is very low. Then, research and development to find energy-saving comminution processes have been performed.
In this paper, the history of research and technique in comminution were reviewed with following items.
1. The measurement and expression of size distribution.
2. The comminution energy.
3. The single particle crushing.
4. The crushing resistance and grindability.
5. The comminution kinetics.
6. The fine grinding.
7. The crushing and grinding equipments.
8. The recent trend according to the questionnaires.

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