Proposal of limit moment equation applicable to planar/non-planar flaw in wall thinned pipes under bending

In this paper, a limit bending moment equation applicable to all types of planar and non-planar flaws in wall-thinned straight pipes under bending was proposed. A system to rationally classify the planar/non-planar flaws in wall-thinned pipes was suggested based on experimental observations focused on the fracture mode. The results demonstrate the importance of distinguishing between axial and circumferential long flaws in wall-thinned pipes.     

Numerical modeling of multiphase diffusion in the process of homogenizing in binary alloys

A general model to treat multiphase diffusion in an impregnated semi-infinite couple, a finite/semi-infinite couple, and a finite/finite couple, under conditions of zero zurface flux, is presented. The model is based both on the numerical solutions previously presented for the multiphase diffusion in semi-infinite and infinite media to which Boltzmann's transformation can be applied and on the finite difference solutions with a variable grid for the multiphase diffusion to which the transformation cannot be applied. Not only critical layer widths for the occurrence of a new phase and the disappearance of a pre-existing phase but also criteria to calculate or not a change in concentration for a terminal phase are introduced in the model in order to diminish the number of iterations, in the calculation. Typical examples to which the model has been applied are discussed.     

Extending image processing strain measurement system to evaluate fracture behavior of wall-thinned pipes

In this paper, an image processing strain measurement system was extended so that fracture behavior of wall-thinned pipes, such as out of plane and large plastic deformation observed in bulging, can be evaluated by the system. Regular grids with nominal size of 10 mm × 10 mm were marked on 100A carbon steel pipes and the images taken with 6 CCD cameras of 15 million pixels were correlated to achieve resolution of 0.3% strain. Strain of the cylinder's outer surface was evaluated by (1) modeling the grids as a cylindrical shell, (2) measuring deformation of the grid on a projected plane, and (3) applying an updated Lagrangian method. The validity of the system was confirmed by applying the proposed system to the burst tests of a wall-thinned cylinder. In addition, the system measured the non-uniform strain distribution that explained the unexpected cracking location.     

Temporal-Talbot-effect-based preprocessing for pattern-effect reduction in all-optical clock recovery using a semiconductor-optical-amplifier-based fiber ring laser

We propose and experimentally demonstrate the temporal-Talbot-effect (TTE)-based preprocessing for the pattern-effect reduction in the all-optical clock recovery using a semiconductor-optical-amplifier (SOA)-based fiber ring laser (SOA-FRL). The TTE-based preprocessing successfully reduced the pattern effects of the recovered clock pulses, so that the 10-GHz clear optical clock pulses were recovered from a 10-Gbit/s return-to-zero on–off keying (RZ-OOK) pseudo-random bit sequence (PRBS) optical signal. “Peak variation” and “Pattern-dependent intensity noise (PDIN)” were proposed and were utilized as parameters to quantitatively evaluate the pattern effects, from which recovered clock pulses suffer, in the temporal domain and the frequency domain, respectively. Peak variation was reduced from 77.2% to 36.2%, and PDIN was improved from ?103 dBc/Hz to ?110 dBc/Hz with the aid of the TTE-based preprocessing. Furthermore, we examined the tolerance of the proposed technique by intentionally deviating the input signal’s bit-rate by ±190 Mbit/s (±2% of the bit-rate) from the optimum condition for the TTE. As compared with the PDIN value for the pulse train obtained by the direct injection of the non-processed signal into the SOA-FRL, the PDIN of the recovered clock pulses using the preprocessed signal indicated improvements over the entire measurement range of ±190 Mbit/s, which corresponds to the wavelength-dispersion deviation of ±56 ps/nm (±4% of the wavelength-dispersion applied to the input signal) from the optimum value.     

Special Silicone Treatments of Anodized Aluminium Surfaces

In a new process for reducing adhesion of ice to aluminium alloy used in refrigerators, an application of a special organosiloxane to the anodized surface is followed by heat treatment. Three organohydrosiloxanes and three variations of heat treatment were examined in respect of their effect on resistance to abrasion and corrosion. The treatments were more effective with 2S grade aluminium than with 3S. The abrasion resistance was increased about tenfold and it is considered that this improvement results from chemical bonding between the organohydrosiloxanes and anodized layers.     

Numerical modeling of multiphase diffusion in the process of homogenizing in binary alloys

A general model to treat multiphase diffusion in an impregnated semi-infinite couple, a finite/semi-infinite couple, and a finite/finite couple, under conditions of zero surface flux, is presented. The model is based both on the numerical solutions previously presented for the multiphase diffusion in semi-infinite and infinite media to which Boltzmann’s transformation can be applied and on the finite difference solutions with a variable grid for the multiphase diffusion to which the transformation cannot be applied. Not only critical layer widths for the occurrence of a new phase and the disappearance of a pre-existing phase but also criteria to calculate or not a change in concentration for a terminal phase are introduced in the model in order to diminish the number of iterations in the calculation. Typical examples to which the model has been applied are discussed.     

Identification of characterization factor for power system oscillation based on multiple synchronized phasor measurements

Electric power systems in Japan are composed of remote and distributed location of generators and loads mainly concentrated in large‐demand areas. The structures having long‐distance transmission tend to produce heavy power flow with increasing electric power demand. In addition, some independent power producers (IPP) and power producer and suppliers (PPS) are participating in the power generation business, which makes power system dynamics more complex. However, there was little observation as a whole power system. In this paper the authors present a global monitoring system of power system dynamics by using the synchronized phasor measurement of demand‐side outlets. Phasor Measurement Units (PMU) are synchronized based on the global positioning system (GPS). The purpose of this paper is to show oscillation characteristics and methods for processing original data obtained from PMU after certain power system disturbances triggered by accidents. This analysis resulted in the observation of the lowest and the second lowest frequency mode. The derivation of eigenvalue with the two‐degree‐of‐freedom model brings a monitoring of two oscillation modes. Signal processing based on wavelet analysis and simulation studies to illustrate the obtained phenomena are presented in detail. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 163(3): 10– 18, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20316     

Gene locus for autosomal recessive distal myopathy with rimmed vacuoles maps to chromosome 9

Distal myopathy with rimmed vacuoles is an autosomal recessive muscular disorder, characterized clinically by weakness of the distal muscles in the lower limbs in early adulthood. Recently, the gene locus for familial vacuolar myopathy with autosomal recessive inheritance (hereditary inclusion body myopathy) was mapped to chromosome 9 by genome-wide linkage analysis of nine Persian-Jewish families. Since both disease conditions share similar clinical, genetic, and histopathological features, we analyzed seven families with distal myopathy with rimmed vacuoles using ten microsatellite markers within the region of the hereditary inclusion body myopathy locus. Significantly high cumulative pairwise lod scores were obtained with three markers: D9S248 (Z(max) = 5.90 at theta = 0), D9S43 (Z(max) = 5.25 at theta = 0), and D9S50 (Z(max) = 4.23 at theta = 0). Detection of obligate recombination events as well as multipoint linkage analysis revealed that the most likely location of the distal myopathy with rimmed vacuoles gene is in a 23.3-cM interval defined by D9S319 and D9S276 on chromosome 9. The results raise the possibility that distal myopathy with rimmed vacuoles and hereditary inclusion body myopathy in Persian Jews are allelic diseases.     

Compact low-cross-polarization horn antennas with serpentine-shaped taper

A compact horn with low cross polarization component less than -35 dB over 5% frequency bandwidth has been obtained by optimizing the taper configuration. To reduce the gain loss caused by spherical wavefront in a short length horn with a large flare angle, a serpentine-shaped taper successfully generates five higher-order modes. Such a taper configuration is represented by varying lengths of various uniform waveguides in stepwise approximation, while keeping the dimension of each step discontinuity constant. As a result, the computational time for obtaining the proposed horn is greatly reduced because scattering matrices of the step discontinuities are pre-calculated before the optimization. The verification of its high performance has been performed numerically and experimentally.