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Many reports describe overestimation of liquefaction resistance based on sounding data related to ground materials containing coarse particles such as gravel and cobbles. Better methods of liquefaction potential estimation must be developed using investigation data other than those from sounding. Gathering perfect and undisturbed samples is difficult, but using seismic methods such as PS logging might be effective for assessing liquefaction potential. For this study, bender element (BE) tests and local small strain (LSS) tests were conducted, respectively, to measure the dynamic and static shear moduli of gravel--mixed sand specimens. Subsequently, relations between liquefaction strength and secant shear moduli were examined to provide reliable estimation of liquefaction in gravel--mixed sand. Although the liquefaction resistance increased considerably with overconsolidation, the initial shear modulus exhibited only a slight change with the same overconsolidation. The experimentally obtained results elucidated that the important shear strain level, for which secant shear modulus has a strong relation with liquefaction strength, was not a linear elastic region of 0.001%: it was about 0.01%. Key words: bender element test, cyclic triaxial test, deformation characteristic, gravel content, liquefaction, overconsolidation, sand. De nombreux rapports decrivent une surestimation de la resistance a la liquefaction basee sur des donnees de sondage relatives a des materiaux broyes contenant des particules grossieres telles que du gravier et des galets. De meilleures methodes d'estimation du potentiel de liquefaction doivent etre developpees a l'aide de donnees d'enquete autres que celles obtenues par sondage. Il est difficile de collecter des echantillons parfaits et non perturbes, mais l'utilisation de methodes sismiques telles que <> peut s'averer efficace pour evaluer le potentiel de liquefaction. Pour cette etude, des essais d'elements piezoceramiques (<>) et des essais de petites deformations locales (<>) ont ete realises, respectivement, pour mesurer les modules de cisaillement dynamique et statique d'echantillons de sable melange a du gravier. Ensuite, les relations entre la resistance a la liquefaction et les modules de cisaillement secant ont ete examinees afin de fournir une estimation fiable de la liquefaction dans du sable melange avec du gravier. Bien que la resistance a la liquefaction augmente considerablement avec la surconsolidation, le module de cisaillement initial ne presente qu'un leger changement avec la meme surconsolidation. Les resultats obtenus experimentalement ont permis de comprendre que le niveau de contrainte de cisaillement important, pour lequel le module de cisaillement secant a une relation etroite avec la resistance a la liquefaction, n'etait pas une region elastique lineaire de 0,001% : il etait d'environ 0,01%. [Traduit par la Redaction] Mots-cles : essais d'elements piezoceramiques, essais triaxiaux cycliques, caracteristique de deformation, teneur en gravier, liquefaction, surconsolidation, sable., Introduction Measurements of soil properties in the ground must be taken to estimate the safety factor of liquefaction, as defined by the ratio between the cyclic resistance ratio (CRR) against [...]

The design of the single-flux-quantum (SFQ) circuits which was estimated by applying over- and under-ground planes to minimize the parasitic inductances to determine its sheet inductances of base and counter superconducting layers is described.

A design of an up/down counter composed of 4-Junction Logic (JL) gates and the digital/analog (D/A) converter using an R-2R ladder circuit is presented to realize the digital flux locked-loop (FLL) circuit. The 4 JL gates with the Superconducting QUantum Interference Device (SQUID) regulator is developed and the correct logic operations are successfully confirmed using fabricated 4JL gates.

Photosensitive polyimide insulation layers are introduced to fabricate superconducting integrated circuits. It simplifies the fabrication process, because the photosensitive polyimide insulation layer can be patterned by conventional photolithography process, resulting in the etching process unnecessary in the present new fabrication process.

An innovative phonon detector in which the integrated coil and the normal-distribution junction are combined is described and discussed.

An Nb-based superconducting tunnel junction (STJs) is fabricated with Al trapping layer using the photosensitive polyimide insulation layer and was detected for X-ray irradiation. It was found that the method of using the photosensitive polyimide insulation layer practically applicable as X-ray detector.

A phonomediated radiation detector using Nb-based superconducting tunnel junctions is developed that are fabricated on an Al2O3 and LiNbO3 substrates. It is found that the maximum pulse height of the phonon events for the LiNbO3 substrate is about twice of that for the Al2O3 substrate.elp

Fabrication of Nb-based suerconducting tunnel junctions (STJ) with [beta]-Ta trapping layers is described and discussed.

In recent years, linear motors are gaining wide popularity in the field of office and factory automation. Therefore, small and high thrust linear motors are needed. This paper deals with a proposal of a new interior permanent magnet type linear pulse motor and it's characteristics. The thrust density of the interior permanent magnet linear pulse motor is larger compared to the other type linear pulse motors. [ABSTRACT FROM AUTHOR]

Studies the properties of NbTiN superconducting thin films prepared by reactive DC magnetron sputtering. Sputtering conditions for NbTiN films; Superconducting characteristics of NbTiN films; X-ray diffraction patterns for NbTiN thin films.

Studies normal-distribution-shaped Josephson tunnel junctions for superconducting tunnel junction photon detector applications. Suppression of the sidelobes of the Josephson current; Magnetic field dependence of the Josephson current of the Josephson junctions.

We have developed a Phononmediated radiation detector using Nb-based superconducting tunnel junctions (STJs). The STJs are fabricated on a substrate as an absorber of the radiation, and a substantial amount of emergent phonons with an energy above the energy gap are detected. The performance of the detector depends on the collection efficiency of the phonon. A selection of an appropriate substrate is required for optimizing the detector performance. We fabricated Nb-bass STJs on a Al2O3 and a LiNbO3 substrates, and compared the pulse heights of substrate phonon events due to X-ray irradiation to the substrates. We found that the maximum pulse height of the phonon events for the LiNbO3 substrate was about twice of that for the Al2 O3 substrate, so that these spectra which was obtained from two STJs showed different shapes, especially the peak due to phonon events. [ABSTRACT FROM AUTHOR]

We have successfully fabricated Nb-based superconducting tunnel junctions (STJs) with β-Ta trapping layers. In an Nb/ β-Ta stacked structure, β-Ta film showed the thickness dependence of critical temperature T[sub c] in current-voltage (I-V) characteristics due to the proximity effect from Nb films. We fabricated Nb-based STJs with Β-Ta trapping layers for X-ray detector working at 0.4 K. We obtained an energy resolution of 52 eV for 5.9 kev X-ray irradiation at 0.4 K. We expect a high energy resolution by optimizing the thickness of Β-Ta trapping layers and improving the fabrication process. [ABSTRACT FROM AUTHOR]

Switching functions using a parallel connection of conventional-type and πtype junctions have been investigated. Both junctions consist of Nb/Au/YBa[sub 2]Cu[sub 3]O[sub 7]-δ Josephson junctions on YBa[sub 2]Cu[sub 3]O[sub 7]-δ edges, whose faces are (110) and (100). The modulation patterns of critical currents in low magnetic fields indicate that the d-wave component is dominant: the (100) junctions exhibit the conventional type, but the (110) junctions the π type. Superconducting current path is alternated between the conventional junction and the π junction by applied magnetic fields using these anisotropic magnetic field dependences of the critical current. [ABSTRACT FROM AUTHOR]

Demonstrates the anisotropic Josephson effect in all (103)-oriented junctions consisting of YBa[sub 2]Cu[sub 3]O[sub 7-delta]/PrBa[sub 2]Cu[sub 3]O[sub 7-delta']/YBa[sub 2]Cu[sub 3]O[sub 7-delta] films. Characteristics of the junction; Use of the junction isolation technology; Exhibition of anisotropic Fraunhofer interference patterns.

We have investigated the magnetic field dependence of the Josephson tunnel junctions whose shape is defined with a normal-distribution function. It was revealed that the normal-distribution-shaped Josephson tunnel junctions show an exponential decay and no side lobes of the Josephson current as the external magnetic field is increased. This behavior was confirmed experimentally by using the Nb/AlO[sub x]/Nb tunnel junctions with a Josephson critical current density of J[sub c]=50 A/cm[sup 2], and an area of 10 000 μm[sup 2] corresponding to the "small" junction region. Normal-distribution junctions should have a potential for wide applications to photon detection since the external magnetic field to suppress the Josephson current can be lowered to less than one tenth that of other junctions reported. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We prepared normal distribution function shaped (NDF-shaped) superconducting tunnel junctions (STJs) with Ta electrodes. Using two different phases of Ta, we successfully prepared STJs with bcc-Ta and β-Ta electrodes. The critical current of the NDF-shaped STJs with Ta electrodes showed an exponential decrease for the applied magnetic field. We determined the coherence length for bcc-Ta and β-Ta combined with Nb at 0.4 K. Coherence lengths were determined to be 21 nm for bcc-Ta and 16 nm for β-Ta combined with Nb. For the quasiparticle trapping and amplification, β-Ta is expected to be a good electrode combined with Nb because of the short coherence length. [Copyright &y& Elsevier]