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The previously reported electrohydrodynamic (EHD) pumps can generate bidirectional flow with asymmetrical performance in two directions. This configuration causes difficulty to control the system that the EHD pump and soft actuators are integrated. This paper proposes a new design with a simple structure to reduce the pressure difference in the two directions of the EHD pump. The EHD pump in this work consists of a flexible cover and base, copper electrodes, and soft fluidic channels, which indicates the flexible properties. We investigate the pressure performance of this proposed EHD pump. Besides, the structure of the EHD pump is optimized in terms of the reduction of pressure difference. Finally, we apply this new pump to drive the soft tube actuator.

A new scheme is proposed for constructing an orbital-specific (OS) exchange-correlation functional that satisfies multiple linearity conditions for orbital energies (LCOEs). The Hartree–Fock exchange portions in the OS exchange-correlation functional, based on a multiply range-separated functional, are set so as to satisfy the multiple LCOEs. The current scheme has also been extended to calculations of core, valence, and Rydberg excitations. Numerical assessments on ionization potentials, electron affinities and excitation energies have confirmed accurate descriptions of core, valence, and Rydberg orbitals by the OS hybrid functional.

The photostability of (E)-2-[3-(2-thioxopyrrolidin-3-ylidene)methyl]-tryptophan ((E)-TPMT), the main yellow pigment in salted radish, was studied. First we analyzed the photoproduct generated from (E)-TPMT under longwave UV irradiation. On the basis of NMR spectroscopy, the photoproduct was identified as Z-configurated TPMT, and isomerization from the Z- to the E-form was reversibly induced by Vis-light irradiation. The optimum wavelength for isomerization from the E- to the Z-form was 360-380 nm, and that for isomerization from the Z- to the E-form was 440-460 nm. The E/Z-ratios in the photostationary state under UV- and Vis-light irradiation conditions were approximately 0.95:1 and 26:1 respectively. The (Z)-isomer was more sensitive to light irradiation than the (E)-isomer in the quantum yield measurement. Yellowing was dependent on the ratio of the (Z)-isomer, because the b(*) and chroma value rose with increases in the (Z)-isomer by the colorimeters. Hence, it is possible that the formation of the (Z)-isomer contribute to the yellow color of takuan-zuke during long salting and fermentation.

We consider a numerical model of pedestrian movement in a counter flow footway using a cellar automaton model. The enter rate of a pedestrian into the footway is the control parameter in our study. The probability of the panic occurrence is calculated statistically. If the width offootway is large, we find critical behavior of the panic probability which is similar to the phase transition obtained from statistical mechanics. We also consider the asymmetric case where the number of pedestrian moving one direction is different form that of the couter direction.

A superconducting tunnel junction (STJ) is very attractive for use in high-energy-resolution photon detectors because of its small energy gap. To detect a single photon, the Josephson current of the STJ has had to be suppressed by an external magnetic field. We demonstrated an on-chip coil-integrated STJ photon detector, which excludes the external magnetic field, allowing a small device size. A normal-distribution function shape was adopted for the superconducting electrodes, which makes the magnetic field supplied to the STJ small. We devise a new superconducting photon detector by combining the above techniques. A new Josephson switching gate is also integrated on the same detector chip in order to drive an on-chip integrated coil by a persistent superconducting current. This behavior was confirmed experimentally using the technology of the fabrication process of the Nb/Al-AlOx/Nb Josephson tunnel junction.

Magnetic field dependence of Fiske steps has been investigated using Nb/Al–AlOx/Nb tunnel junctions formed with a normal-distribution function with a dispersion parameter of σ= 0.45. Fiske steps are due to the different resonance mode appearing in the current–voltage characteristics when an external magnetic field is applied to the junctions at 4.2 K. Both positions in the voltage scale and current amplitude of Fiske steps were systematically measured. We found that the amplitudes of the Fiske steps increased gradually, and then decreased monotonically with an increase in magnetic field. All Fiske steps almost completely disappeared at a magnetic field of less than 1 mT, at which the dc Josephson critical current also decreased to less than 10-3 of the maximum. The position of Fiske steps in the voltage scale was analyzed using a diamond-shaped junction which corresponds to a 45-degree-rotated square junction.

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.

Dynamics of gap solitons in various kinds of polyatomic chains are analyzed comprehensively. First, we consider a case that the periodic modulation of the anharmonic lattice parameters is small (shallow grating) and obtain coupled mode models between the forward and backward propagating waves at the Bragg wavenumber. Depending on the period of the chain N (>1) and on the nonlinearity, we derive four types of coupled mode equations. Moving localized solutions for gap solitons are obtained analytically. It is found that owing to the quadratic nonlinearity, static dc waves should be taken into account, which leads to the concept of “ dynamical rectification ”. The theoretical results for gap solitons are checked by numerical simulations. Secondly, we consider the case of large modulation of the lattice parameters (deep grating). We develop a theory of the nonlinearity-induced carrier-wave modulations of the lattice mode dynamics (Bloch wave) and derive the effective nonlinear Schrodinger equation. Numerical ...

The frequency dependence of the acoustic radiation pressure on a solid elastic sphere placed freely in an incident plane progressive sound field in water has been investigated. In particular, the behavior of the acoustic radiation pressure at resonance frequencies of the elastic vibration of the sphere has been studied theoretically by taking into account the three components of the radiation pressure, namely, kinetic energy, potential energy, and tensor term. It has shown that the contribution of potential energy to radiation pressure is the largest and it has a positive value, that which of kinetic energy is rather small and has a negative value, and that which of tensor term is so small as to be negligible in the cases far from resonance frequencies. At resonance frequencies, potential energy falls off rapidly, while the softer the material are, the greater positive values kinetic energy and tensor term are increased up to, with a few exceptions. As a result, there takes place, in general, a series of maxima in the frequency characteristic curves of radiation pressure for relatively soft materials such as lead, and a series of minima for relatively hard materials such as iron at the resonance frequencies, because the increase in kinetic energy and in tensor term overcome the decrease in the potential energy for relatively soft materials. Materials of intermediate hardness such as brass have the frequency characteristic curves mixed by maxima and minima.

We consider pulse propagation in quadratically nonlinear gratings. Assuming that the phase mismatch between the fundamental and the second-harmonic frequencies deltak is large, we present a perturbation method in deltak(-1). In the well known cascading limit, terms to deltak(-1) are kept; here we keep terms to deltak(-2), which leads to another type of coupled mode equations. Numerical calculation of the full equations support our theoretical results.

Each of all the existing theories of the acoustic radiation pressure has, of course, peculiar excellent advantages.It is also the fact, however, that there are more or less ambiguities, leaps in logic, and unnecessary assumptions in many existing theories.The purpose of the present paper is to develop a general theory that covers both the Rayleigh and Langevin radiation pressures, and is simple and easy to understand, with merits of existing theories incorporated as far as possible.We distinguish between the Rayleigh and Langevin radiation pressures according as the force acting on an obstacle depends on a fractional change in static pressure or not.Since it is a matter of the experimental conditions whether one observes the Rayleigh radiation force or the Langevin radiation force, both radiation forces should be treated theoretically from a common physical point of view.The emphasis is placed on pointing out that the tensor properties cannot be disregarded in the Rayleigh radiation pressure as well as in the Langevin radiation pressure, by showing where the tensor term originates in.A brief review is given for a few of existing theories at the end of the chapter.

Interactions between nonlinear media and an object in it are studied theoretically and numerically using dynamical models. The KdV soliton is incidented to the object by numerical simulation and the generation of solitons are detected. The measured amplitudes coincide very well with the theoretical results.

Optical solitons in fiber grating in which the dielectric constant varies periodically along it, are investigated. It is proved that the envelope of the Bloch wave obeys the nonlinear Schrodinger equation. As an application, gap solitons in a super-lattice are discussed. The concept and method presented in this paper are useful not only for explaining recently observed Bragg grating soliton but for analyzing a large class of nonlinear periodic systems.

The present paper deals with the Rayleigh radiation pressure which is defined as the time-averaged force per unit area of the wall of a closed vessel when an acoustic field is applied. Previous theories on the Rayleigh radiation pressure are examined critically and erroneous results are noted and rectified. A new theory of radiation pressure on a partially reflecting plate is developed as a function of the linear reflection coefficient and transmission coefficient of the plate. It is shown that the time-averaged Lagrangian pressure does not depend on the Lagrangian coordinate and that the effects of acoustic straining cannot be disregarded even in the presence of reflected waves in a closed tube. The present theory is applicable to various types of reflectors. The principal conclusion of this work is that the Rayleigh radiation pressure on a perfectly absorbing plate and that on a perfectly reflecting plate are both given by (γ+1)‹E›/4, where γ is the ratio of specific heats of the medium and ‹E› is the time-averaged energy density.

Scattering of the nonlinear Schrodinger (NLS) solitons in discontinuous media is studied numerically. As a physical model, one-dimensional anharmonic lattice which has a discontinuity in its mass distribution, is analized. After the collision of the incident NLS soliton against the mass interface, we detect the amplitude of the reflected and transmitted solitons. They coincide very well with those of the theoretcal ones (T. Iizuka and M. Wadati, J. Phys. Soc. Jpn. 61 (1992) 3077), which is based on the inverse scattering method.

The scattering of nonlinear Schrodinger solitons due to an impurity in anharmonic lattices is studied numerically. At most one soliton is generated in both reflected and transmitted waves. Their amplitudes coincide very well with those of the theoretical result, which has been obtained through the inverse scattering method.

Small amounts (up to 0.1%) of C60 and C70 have been detected by high-pressure liquid chromatographic (HPLC) analysis of toluene extracts from soots used to manufacture Chinese ink sticks, or Sumi. These soots have been prepared by slow burning of pine wood, and later various seed oils. Turpentine oil, the major constituent of pine wood oil, have been found to produce twice as much fullerenes as does toluene when used as the combustion material. The yields of fullerene from unsaturated combustion materials decrease with the iodine number, reaching zero in the saturated compounds. Possible role of fullerenes as the effective gloss enhancer for black color is suggested in reference to the known technique of adding a natural red pigment to Sumi practiced in Japan.

Using a recently presented theory of nonlinear periodic systems, we investigate wave propagations in anharmonic periodic lattices. If the system is linearized, it has Bloch type solutions which are regarded as an extension of the monochromatic waves. It is shown that the modulations of the Bloch wave due to the nonlinearity and the dispersion obey the nonlinear Schrodinger equation. One of the important results is that envelope soliton propagates in the periodic lattices.

Nonlinear short pulse propagations in birefringent optical fiber are studied. A new nonlinear evolution equation is presented, which is a hybrid of the coupled nonlinear Schrodinger equation and the coupled derivative nonlinear Schrodinger equation. As a solution for the coupled hybrid nonlinear Schrodinger equation, solitary waves (pulsed electric fields) propagating at a constant speed are obtained.

The curve lengthening equation is a geometric model where the normal velocity U of the curve is a linear functional of the curvature κ , that is, U =-κ+ c ( c is a constant). Exact solutions for the curve lengthening equation are found. They include generalizations of the Saffman-Taylor finger. The spiral solutions and their pitches are also discussed.

This paper examines regional difference in distance-decay parameters of a doubly-constrained gravity model, using a data set of the 1985 inter-municipal migration in Japan. The parameters are estimated for each of 28 prefectures. The model provides reasonably good representation of migratory flows for all the prefectures (Table 3).The distance-decay parameters are distributed roughly in such a way that the prefectures of central Japan have more-negative estimates and those of peripheral Japan have less-negative estimates (Fig. 2) as if a nationwide map-pattern effect were operating. Simple correlation analyses reveal that the distance-decay parameter is significantly correlated with demographic variables relavant to migration volume and population size as well as socio-economic variabels, but rarely correlated with map-pattern variables (Table 4).A stepwise multiple-regression analysis is employed to regress the distance-decay parameter on only those significant at the 0.10 level or less, among the 46 independent variables. As a result, 56% of the total variance is accounted for by 4 variables (Table 5): population density, growth rate of manufacturing workers, physical-structure index (Griffith and Jones, 1980) capturing a prefecture-specific map-pattern effect and out-migration volume from prefectures.Taking into account their signs of standardized partial regression coefficients, it is concluded that the distance-decay parameter is more-negative in the prefectures which are high-densely inhabited, which suggests, in a sense, that urbanization has reached an advanced stage, where municipalities are well connected, where industrial locations have recently become stagnant and where large migratory outflows from prefectures do not take place, and vice versa.

Using the inhomogeneous KdV equation, statistical behaviors of solitons in random systems are investigated. The randomness is assumed to have a long-range correlation that decays algebraically with an exponent −γ 1, the solitons diffuse normally. However, if γ⩽1, anomalous diffusion of solitons is observed.

Scattering of weakly nonlinear waves in a one-dimensional anharmonic lattice due to a very heavy impurity is investigated. Lattice waves are assumed to be slowly varying. The incident, reflected and transmitted waves are governed by the Korteweg de Veries (K-dV) equations on different coordinates. We analytically construct the transmitted and reflected waves from the incident wave. In particular, scattering of an incident soliton is analyzed. It is shown that at least one soliton is always generated both in the transmitted and the reflected waves. More than two transmitted solitons are generated if the mass of the impurity is large enough. We also evaluate the amplitudes of the reflected and transmitted solitons.

A two-dimensional anharmonic lattice which has a line discontinuity in the mass distribution is considered. We study scattering of the nonlinear waves due to the mass interface. In the continuum approximation, the incident, reflected and transmitted waves are shown to obey three independent KP equations. By solving the KP equations for sech 2 -type intial values, we investigate effects of the discontinuous interface on the developement of the incident line soliton. It is shown that the transmitted line soliton breaks up while the reflected soliton does not. The reflection angle is different from the incident angle due to the nonlinearity. These are considered as features of nolinear refraction and reflection phenomena. Our approach is applicable to other two-dimensional nonlinear systems such as shallow water and ion acoustic wave.

Scatterings of nonlinear lattice waves by a mass impurity are studied. The waves are assumed to be nonlinear modulations of the monochromatic waves. Due to the impurity there appear the incident, reflected and transmitted waves. We show that the three waves are described by independent Nonlinear Schrodinger (NLS) equations respectively. Using the continuity conditions of the waves at the impurity site, we analytically construct the transmitted and reflected waves from the incident wave. As an application, scattering of an incident NLS envelope soliton is investigated. We find that at most one soliton is generated both in the reflected wave and in the transmitted wave.