In this paper, we discuss a current testing method, which aims to reduce testing costs on CMOS Static RAMs (SRAMs). As the fault models on a memory cell, we assume a hard short between two signal lines, a hard open on signal line, a transistor stuck-on fault, and a transistor stuck-open fault. Proposed test method is based on the simulation results of electrical behavior on the faulty memory cell. In this test method, decoder circuits and bit lines are modified to drive all the memory cells of SRAMs simultaneously. Since the faults are detected by only observing the power supply current, the test sequence becomes simple, and it does not dependent on the size of the memory cell array.

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Beginning of the repeatedly wear, severe wear condition of high wear rate becomes predominate. The wear rate decreases with time and the wear condition changes to a mild wear. After that, a wear becomes hardly advance and becomes stable condition. An oxide film forms at a worn surface and the surface geometry becomes smooth. That condition is called “running-in”. The transition mechanism from severe to “running-in” is important for constant operation of the machine that has a mobile components contacting among metals. A drying repeated wear test of a pin on disk was studied under unlubrication condition in this report. Also, a change of a running-in process in magnetic field has been studied. The results are reported as follows.

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Comminution is the oldest mechanical unit operation for size reduction of solid materials and an important step in many processes where raw materials are converted into intermediate or final products. Limestone is self-sufficient mineral resource in Japan and has been using as a sample for grinding tests.
Recently, a demand for fine or ultra-fine particles is increasing in many kinds of industries.
The energy efficiency of comminution is very low and the energy required for comminution increases with a decrease in feed or produced particle size. Research and development to find energy-saving comminution processes have been performed. Then, it is necessary to estimate the comminution energy. Bond had proposed Work Index and it is an important factor in designing comminution processes and has been widely used. The measurement procedure of Work Index is closely defined by JIS. In a previous paper, the authors proposed a corresponding Work Index which is proportional to the Work Index. A corresponding Work Index could be estimated by the examination of the zeroorder increasing rate constant of mass fraction less than a evaluating size using an arbitrary ball mill.
In this paper, ball mill, vibration mill and planetary mill grinding, compressive crushing of powder bed, and autogenous grinding with a stirred mill were carried out on limestone. The relationships between the corresponding Work Index and the evaluating size (sieving size) were studied.
As a result, the corresponding Work Index had the minimum value when the evaluating size was approximately the grain size of limestone in the five kinds of mills.

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Dielectric dispersion in the low frequency range (1mHz-1MHz) was investigated for the (CaSr) (TiZr) O₃ system fired in a reducing atmosphere. The effects of composition, firing conditions and microstructure on dielectric dispersion at low frequencies were investigated using thermally stimulated current (TSC), dc electrical conductivity and dielectric loss (tan δ) spectroscopy measurements. The activation energy obtained from the relaxation time, dc electrical conductivity and thermally stimulated current (TSC) was 0.9eV in each case. The dielectric dispersion in the low frequency range was considered to be due to electrons excited from oxygen vacancies.

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Today, the parts of computer and communication instrument are requested to be accurate and reliable. Many parts in instruments are ceramics and are produced via powder handling on the way of the ceramics manufacturing processes. In this case, the final performance of products are effected by the powder handling. First of all the bulk density of powder has some effects on sintered powder compact. This shows that even if chemical components are same, the final performance of products are different each other depending on bulk density.
In this paper, the application of electrostatic effect on initial bulk density of powder in a cell is taken notice. And it is experimentally discussed using X-ray radiograph system. As the results, average equivalent bulk density at one point packing is pointed out to decrease as applied voltage increases, and at two point packing it keeps constant independent of electrostatic effect.

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The presence of hematite phase in CaO-Fe₂O₃-SiO₂-Al₂O₃ quaternary calcium ferrite hinders to clarify the final fractional reduction and the formation of a intermediate mineral phase on initial reduction steps of its calcium ferrite.
Therefore, the preperation of hematite free quaternary calcium ferrite was tried, and the final fractional reduction, structure and composition on the initial reduction steps of resultant samples have been investigated, and the chemical molecular formula of a intermediate mineral phasses was calculated reasonably.
The main results obtained are as follows:
1) It was recognized that preperation of hematite free quaternary calcium ferrite from the initial mixture corresponding to composition of CaO·SiO₂-2 (Fe_0.89Al_0.11) ₂O₃ (SiO₂=6.74mass%) was possible under the condition of heating temperature 1723K, retention time 1200s and cooling rate 0.083K/s, while it was impossible from initial mixture of CaO·SiO₂-3 (Fe_0.89Al_0.11) ₂O₃ (SiO₂=6.74mass%).
2) In the changes from 5 to 45% of CO concentration in CO-CO₂ mixed gases, the final fractional reduction were about from 5 to 45% at the temperature 1023K-1173K.
3) From the reasoning calcuration of the analytic values of reduced samples by EPMA, it was showed that the chemical molecular formula of a intermediate mineral phasses formed on initial reduction steps of quaternary calcium ferrite (SiO₂=6.74mass%) were the solid solutions of SiO₂-3CaO·FeO·7 (Fe_0.82Al_0.18) ₂O₃, SiO₂-4CaO·FeO·4 (Fe_0.86Al_0.14) ₂O₃ and SiO₂-CaO·3FeO· (Fe_0.74Al_0.26) ₂O₃, and Fe₃O₄, FeO, “FeO·CaO” (solid solution involved SiO₂ & Al₂0₃) and 2CaO·SiO₂.
4) The formation of expected and CaO·FeO· (Fe_xAl_1-x) ₂O₃ in during the initial reduction of samples were not recognized.

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Effect of dispersive media on the density has been investigated for the green sheets prepared by the doctor blade method. Difference of dispersing level contributed to sediment density of ceramic oxide powder Pb (ZrTi) O₃ at suspension. For the paste, the kind of dispersive media changed the degree of dispersion. These phenomena were also observed in the paste with the addition of surface-active agents. In the case of low dispersion, cohesive particles sunk during drying process and the green sheets had a gradation in density toward thickness.

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Carrier magnetic separation of fine wolframite (-5μm) was investigated using coarse magnetite (37-53μm, etc.) as carriers and sodium oleate as a surfactant by high gradient magnetic separator. Effects of some factors on the carrier magnetic separation were studied. It was found that the recovery of fine wolframite was significantly increased from about 23% by conventional magnetic separation to 94% by carrier magnetic separation at magnetic flux density 0.14T. The recovery of fine wolframite was improved from 50% to 93% by carrier magnetic separation at 0.27T for a mixture of wolframite (-5μm) and quartz (-10μm) containing 10.9% WO₃.
The improved results of magnetic separation were mainly explained by the size enlargement of the fine wolframite due to the addition of carriers and stirring at high speed. The collision energy between the coarse and fine particles is much greater than that between fine particles. Therefore, aggregation be tween coarse and fine particles occurs more easily. The stability of aggregate of particles is also strengthened due to the hydrophobic forces between particles with the addition of sodium oleate.

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Various methods to measure and predict binary mutual diffusion coefficients for polymer-solvent systems are reviewed. Typical concentration dependent mutual diffusion coefficients are illustrated and their features are described. Several methods to measure them are also shown. In addition, one of the useful methods based on a dissolved solid coordinate technique is explained in detail and an example is given for the acrylic adhesive-acetone system. Furthermore, three theoretical models to predict the mutual diffusion coefficients are introduced and the predictive ability of each model is discussed.

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Removal of sulfur, nitrogen and ash-forming minerals from coal by pretreatment is one of the promising technologies not only to lower the damage of environment but also to accelerate the development of efficient coal utilization processes. This review concerns sulfur in coal which causes air pollution and acid rain in the world. The origin and forms of sulfur in coal, analytical method of sulfur forms, distribution of sulfur in macerals, sulfur behavior during heat treatment, and advanced desulfurization technologies are discussed.
Sulfur in coal was derived from (1) sulfate in sea water that overlaid peat swamps and (2) parent plant material. Lower density group of organic matrix which is composed of exinite and vitrinite contains high sulfur. XANES analysis indicates that the low-density group contains sulfide and sulfoxide, which could contribute to the high extent of organic sulfur removal during rapid pyrolysis. Ferrous-sulfide sulfur and thiophene remains in char.
A combined process of alkali treatment with rapid pyrolysis is introduced which has aimed to transform the thermally stable form of organic sulfur to reactive species before pyrolysis. More than 90 % of organic sulfur has been removed from a subbituminous coal.

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The various methods of the non-empirical atomic structure calculations have been so far extensively developed. Their representatives are the Thomas-Fermi, the Hartree, the Hartree-Fock and the density functional methods. These methods have been also applied to the understandings of the physical and the chemical properties for the molecules and the solids. In this review article, mainly the Hartree-Fock and the density functional theories for the atoms are described, and furthermore the methods for the numerical calculations of the basic equations are given. The fundamental physical pictures in the many electron systems are almost included in the HF theory, and the theory is the most standard one in the many body problems even at the present day. The density functional theory is a newer one and originates from the Thomas-Fermi theory, and has merits that the numerical calculations in this method are very easy compared to the HF method and give the similar accuracy to that of the HF method. The studies to improve and to develop the density functional theory are now still continuing. On the other hand, since the relativistic effects are important for the heavier atoms such as the rare earth and the actinide, the fundamentals for the relativistic atomic structure calculations are also given.

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