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In the fabrication process of medicine tablets, working speed of the tablet compressing is an important factor to realize the high fabricating efficiency together with the low cost. Thus, a number of loadings would be applied with very high frequency to tips of a couple of compressing punches. Sometimes, the tablet compressing speed exceeds 150 tablets per second. Due to such a circumstance, the very high cycle loadings are applied to the tips of the compressing punches making medicine tablets. The high strength steel of KNS-ES was specially designed and fabricated for the particular use as the compressing punches. In this study, very high cycle fatigue tests were performed in the loading type of rotating bending in order to obtain the fundamental S-N property of this steel. Based on experimental results, the S-N property in giga-cycle regime was discussed including the effect of the residual stress on the S-N properties. Consequently, the duplex S-N curves were clearly found, but the surface-induced fractures were often found in the fatigue data belonging to the second S-N curve in the longer life region.

In order to investigate the fatigue characteristics of metallic materials experimentally, a long period of time is required to get sufficient number of S-N data. In recent years, in order to overcome this difficulty, multi-type rotating bending fatigue testing machine whose name is GIGA QUAD have been developed by Yamamoto Metal Technos Co., Ltd., in which four specimens can be tested simultaneously. In this time, some additional new functions have been developed as follows; (1) 'high and low temperature environmental testing unit' whose target temperature is in a range of 600°C and -150deg.C, (2) 'constant temperature/humid environmental testing unit' combined with the conventional corrosive cell, (3) ‘fracture alarm unit’, and (4) ‘2-step variable loading unit’. By combining these new functions with the machine of GIGA QUAD, one can perform the fatigue tests efficiently corresponding to the respective requirements for researchers in both of academic and industrial sectors.

In order to investigate very high cycle fatigue characteristics of the Zr55Al10Ni5Cu30 (in at.%) bulk amorphous alloy, fatigue tests were performed in rotating bending at a frequency of 52.5 Hz with a stress ratio of R=-1. The test environment was in room atmosphere without any control of temperature nor humidity. The fatigue endurance limit σw of the bulk amorphous alloy was about 700 MPa and the fatigue strength ratio σw/σB (fatigue endurance limit divided by the ultimate tensile strength) was found to be 0.38. Fracture surfaces of failed specimens were observed by scanning electron microscope (SEM). The fracture surface was separated into three typical regions; (1) multi-facet region, (2) stable crack propagation region and (3) instantaneous fracture region. The cracks took place on the specimen surface and fatigue striations were clearly formed in the stable crack propagation region on the fracture surface. A distinct boundary was observed between the stable crack propagation region and instantaneous fracture region. The instantaneous fracture region was covered by the dimple-type morphology. Vein-like patterns peculiar to the static fracture surface of amorphous alloys were also found in the edge region of the fracture surface. The fatigue fracture toughness of this bulk amorphous alloy was in the range of 20-29 MPa·m1/2.

This paper describes a parallel associative processor, lXM2, developed mainly for semantic network processing. IXM2 consists of 64 associative processors and 9 network processors, having a total of 256K words of associative memory. The large associative memory enables 65,536 semantic network nodes to be processed in parallel and reduces the order of algorithmic complexity to O( 1) in,basic semantic net operations. It is shown that IXM2 has computing power comparable to that of a Connection Machine. Programming for lXM2 is performed with the knowledge representation language IXL, a superset of Prolog, so that IXM2 can be utilized as a back-end to AI workstations.

Patterned TiO2 stripes were formed on a sol-gel crystalline WO3 film by using a chemically modified sol-gel method (pat-TiO2/WO3), and the coupling effect on the photocatalytic activity was studied. Although the photoinduced electron transfer from TiO2 to WO3 was confirmed by labeling and visualization of the reduction sites with Ag particles, the photocatalytic activities of TiO2 for both the gas-phase oxidation of CH3CHO and the liquid-phase oxidation of 2-naphthol decreased significantly with the coupling. This finding was rationalized in terms of the decrease in the rate of the electron transfer from the semiconductor-(s) to 02 with the coupling, which was estimated from the kinetic analysis of the photopotential relaxation. When the excited electrons were removed by a SnO2 underlayer, the WO3 film exhibited a high photocatalytic activity exceeding that of TiO2 for the oxidation of 2-naphthol.

Microcomputer application status in Japan is introduced. Six themes are studied: the status of application systems, expected functions of microprocessors in each application field, the one-chip microcomputer, software developments, multimicroprocessor systems, and expected or new applications. These are the results of the activities of the six Working Groups of the two Specialized Committees in JEIDA, Japan Electronic Industry Development Association, in fiscal 1977.