Centrifuge Tests of Impulsive Vertical Acceleration Generated by Foundation Uplift During Strong Shaking

Dynamic centrifuge tests were performed using soil-footing-superstructure models to investigate the effects of the roughness of the soil-footing interface on the uplift and the resulting vertical acceleration of the footings during strong shaking. Four footing models, each of which had a smooth or rough surface and was embedded or not embedded in soil, were subjected to strong shaking. The horizontal shearing and the vertical compressive forces on the base of each footing, as well as the earth pressure and the wall friction forces on the active/passive sides of each footing, were elaborately measured with newly developed 2D load cells. It was shown that (1) the collision impulse of the uplifted footing against the ground induced an extremely high vertical acceleration of the structure, which was much larger than could be induced by the vertical movement of the gravitational center of the structure; (2) the vertical acceleration caused by the collision impulse increased with the induced rotation angle of the footing; (3) if the footing was not embedded in the ground, the rotation angle and the resulting vertical acceleration tended to be larger for the rough footing than for the smooth footing, probably because the larger horizontal sliding of the smooth footing was able to reduce the footing rotation; and (4) if the footing was embedded, by contrast, the rotation angle and the resulting vertical acceleration tended to be smaller for the rough footing than for the smooth footing, probably because the larger wall friction that developed on the passive side in the rough footing was able to reduce the footing rotation.     

Mechanical properties at sub-microscale and macroscale of polycrystalline uranium mononitride

The indentation hardness, Vickers hardness, fracture toughness, and Young’s modulus of polycrystalline uranium mononitride (UN) at sub-microscale and macroscale were evaluated by an indentation test, Vickers hardness test, and the ultrasonic pulse echo method. The Young modulus and Vickers hardness were in good agreement with the literature values. The fracture toughness of UN was about three times that of UO₂. In addition, we revealed the indentation size effect on the indentation hardness of UN.     

Parallel video signal processor configuration based on overlap-save technique and its LSI processor element: VISP

A parallel signal processor architecture has been developed for real time motion picture encoding. The architecture is based on spatial parallelism utilization in a picture signal. Plural element processors handle subregional pictures simultaneously without communicating with other element processors. However, due to an overlapsave technique where every sub-picture input area is chosen to be wider than the output area, element processors can carry out continuous processing over an entire picture. In order to increase motion picture processing efficiency as well as system implementation simplicity, a specific element processor LSI chip, composed of a pipeline arithmetic unit, two dimensional address generators, a raster scan signal handler, and a sequence controller, has been developed by using more than 220,000 transistors. The developed parallel processor is shown to be applicable to a software programmable low bit rate TV codec.     

Unified analysis of postdetection diversity for binary digital FMmobile radio

An analysis is presented of postdetection diversity using both selection combining and general combining for the reception of a binary digital FM signal in a Rayleigh fading environment. Noncoherent (differential and frequency) demodulation is assumed. In the general combiner, the output of each branch demodulator is weighted by the νth power of the demodulator input signal envelope (weighting factor). The optimum weighting factor is found to be ν=2. It is shown that postdetection general combiners using weighting factors of ν=1 and 2 correspond to predetection equal-gain and maximal-ratio combiners, respectively. A closed-form solution and a fairly simple expression are derived for the average bit error rate. Numerical calculations show that the postdetection two-branch diversity gain is only about 0.9 dB inferior to the predetection system when minimum shift keying (MSK) is used     

Influence of pulsed electric field on enzymes,bacteria and volatile flavor compounds of unpasteurized sake

A pulsed electric field(PEF) was applied to unpasteurized sake at constant temperatures, at which α-amylase was not inactivated. We adjusted the input energy to be identical for the temperatures by changing the number of PEF application, because the current significantly increased with the temperature, even the amplitude of the applied voltage was identical. As a result, the α-amylase was seemed to be inactivated by PEF application, not due to thermal effect.The glucoamylase was significantly inactivated by PEF. Moreover, the acid carboxypeptidase was inactivated by PEF at 4 °C but significantly activated at 25 °C. These results show that the sensitivity of enzyme to PEF application differs depending on the types of enzyme and treatment temperature. On the other hand, the colony number of bacteria was remarkably decreased, but the amount of the volatile flavor compounds was not decreased by PEF application.     

Analogue baseband TV transmission experiments using semiconductor laser diodes

The transmission characteristics of analogue video signals are investigated by using semiconductor laser diodes. It is shown that the linearity degradation due to speckle noise depends on the optical-fibre types adopted. Based on this investigation, transmission over 32 km is carried out by using a 1·3 ?m laser diode and single-mode fibres, with 46 dB unweighted s.n.r.     

An image processing method for scanning electron microscopy based on the information transmission theory

Based on the information transmission theory, topographic image signals in scanning electron microscopy are used to evaluate contrast, gradient, acutance, and Laplacian operator, the total of which represent the image sharpness of an edge line. One may consider the impulse and step functions as an input to the Gaussian system function of a low-pass filter, the impulse and step response functions possibly representing a single spot and image contrast of an edge profile, respectively. It is shown that the response function of acutance defined as the power of the gradient normalized by density is a more realistic representation of image edge sharpness. Also, edge sharpness can be greatly enhanced by utilizing the Laplacian operator through digital image processing for a disk specimen model with a rounded edge. Contrast increased by specimen tilt, and an edge effect due to side-scattered electrons, as well as the signal attenuation by specimen collection, are consistently obtained as the response function in the system. The exact measurement of spot size and edge-to-edge resolution, and image sharpness improvement, are derived by digital image processing.     

Synthesis and application of fluorine containing graftcopolymers

Summary Well-defined graftcopolymers were prepared by radical copolymerization of methyl methacrylate macromonomer with perfluoroalkyl acrylate. Contact angle of the solvent cast films of poly(methyl methacrylate) containing various amount of the graftcopolymer was measured against water droplet. Addition of 0.2 wt% of the graftcopolymer was sufficient to improve the polymer films to water repellent surfaces, while 10 wt% was necessary to modify the polymer surfaces to the same level of water repellency.     

Computer-aided protective system hazard analysis

Based on a fault tree for a plant and on two fault trees for its protective system, the computer code, PROTECT, produces time profiles of expected numbers of normal trips, spurious trips, and destructive hazards. Input parameters to PROTECT are (1) minimal cut sets of the fault trees; (2) mean time to failures of basic components; (3) failure characteristics of operators; (4) scheduled maintenance intervals for plant and protective system; and (5) repair times from normal and spurious trips. Using the code, we can design the protective systems and maintenance policies, keeping both destructive hazards and spurious trips below acceptable levels.     

Clustered localization of oligomeric Nef protein of human immunodeficiency virus type 1 on the cell surface

We studied human immunodeficiency virus type 1 (HIV-1) Nef protein biochemically and histologically. HIV-1 Nef, derived from baculosystem and from cells infected with HIV-1, formed homomeric monomers, dimers, trimers, and further polymers. These oligomers were non-covalently associated. In cells infected with HIV-1, Nef molecules were clustered at the cell surface as well as cytoplasm. Our previous results have indicated that the Nef on the surface of cells infected with HIV-1 is cytotoxic against uninfected CD4+ T cells. Thus, it is very likely that the HIV-1-mediated cytotoxic reaction is due, at least in part, to the clustered localization of oligomeric Nef on the cell surface.