A DIRECT PERTURBATION THEORY OF THE NONLINEAR SCHR?DINGER EQUATION WITH CORRECTIONS

An exact direct perturbation theory of nonlinear Schrodinger equation with corrections is developed under the condition that the initial value of the perturbed solution is equal to the value of an exact multisoliton solution at a particular time. After showing the squared Jost functions are the eigenfunctions of the linearized operator with a vanishing eigenvalue,suitable definitions of adjoint functions and inner product are introduced. Orthogonal relations are derived and the expansion of the unity in terms of the squared Jost functions is naturally implied. The completeness of the squared Jost functions is shown by the generalized Marchenko equation. As an example,the evolution of a Raman loss compensated soliton in an optical fiber is treated.     

VARIATION OF THE INTENSITY OF ULTRAHIGH ENERGY γ-RAYS WITH ALTITUDE

Intensities of ultrahigh energy γ-rays observed in Chinese emulsion chamber experi ments at several altitudes, including Yunnan Station (3200 m), Mt. Kambala (5500 m), and the foot of Mt. Qomolangma (Everest, 6500m) are summarized. An intensity altitude relation and in particular, the attenuation length of γ-rays at the foot of Mt. Qomolangma are presented.     

A STUDY OF THE FS-PDMP SYSTEM

A signal detection system,which consists of a Frequency-Stepping signal source and a corre-sponding Post-Detected-Matching-Processor,has been studied both theoretically and experimentally.The characteristic function determining the detection performance of the FS-PDMP system is derivedand a set of equipment,which can generate and process an eight-unit long signal with an arbitraryFS mode,has been made for the experimental studies.Some primary results are reported and theyare in conformity with the theoretical analysis.     

THE STUDY OF HORIZONTAL DIRECTIVITY OF CYLINDRICAL(ARC)ARRAYS WITH BAFFLE

The influence of baffle on horizontal directivity and the frequency response of elements is analysedin detail in this paper.Some formulas of calculating the received response and the horizontal directi-vity of the cylindrical(arc)array are given.The influence of parameters of arrays on the performanceof the array is discussed.A comparison between the theoretical values and a part of the experimentalresults is shown.     

SPECTRUM OF THE MICROMASER INJECTED WITH Λ-TYPE THREE-LEVEL ATOMS

The spectrum of the micromaser injected with Λ-type three-level atoms is studied. The spectrum has a Lorentzian lineshape and its central frequency has a shift. The effects of various parameters (for example, the atomic center-of-mass velocity, the cavity-length, the one-photon detuning, the ratio of the atomic injection rate to the cavity decay rate and the number of thermal photons) on the linewidth and the frequency shift are examined. The spectrum shows very different features in different velocity regimes, i.e., in the fast-atom regime, in the intermediate-velocity-atom regime, and in the slow-atom regime.     

SPECTRUM OF THE MICROMASER INJECTED WITH Λ-TYPE THREE-LEVEL ATOMS

The spectrum of the micromaser injected with A-type three-level atoms is studied. The spectrum has a Lorentzian lineshape and its central frequency has a shift. The effects of various parameters (for example, the atomic center-of-maas velocity, the cavity-length, the one-photon detuning, the ratio of the atomic injection rate to the cavity decay rate and the number of thermal photons) on the linewidth and the frequency shift are examined. The spectrum shows very different features in different velocity regimes, i.e., in the fast-atom regime, in the intermediate-velocity-atom regime, and in the slow-atom regime.     

A NEW METHOD FOR THE DETERMINATION OF THE SPIN OF ξ(2230)

In this paper we have got the angular distributions of the photon for the moments of process e⁺e^－→J/ψ→γB(J^η),B(J^η)→P₁P₂. It provides a new way to determine the spin of ξ(2230).     

THE ACOUSTIC POWER OF A PULSED SOUND

A metrological principle for pulse acoustic power,based on the envelope value of the acoustic pressure,isproposed.The deduced value may be defined as pulse acoustic power.Thus in combination with the existedterms for ultrasonic power,a complete system of the terminology can then be fulfilled.     

THE ENVELOPE SOLITON OF STRESS WAVE ON THE WALL OF A FLUID-FILLED CIRCULAR TUBE

The reductive perturbation method of multiple-scales is used to investigate the weak nonlinearmodulation of the stress wave on the wall of a fluid-filled elastic circular tube.In the case of a singlemode,the nonlinear Schrodinger equation which the wave amplitude satisfies and its envelope soliton so-lution of stress wave are obtained.     

ANALYSIS OF THE LOWER MODES OF FREE VIBRATION OF A PIEZOELECTRIC CERAMIC DISK POLARIZED IN THE THICKNESS DIRECTION

By means of the adjoints method of solving the differential equations of two-point boundaryvalue problems,the equations of motion of a boundary stress-free ceramic disk vibrator polarizedin the thickness direction are solved by numerical integration.The resonance frequencies of the lowermodes of radial vibration under the influence of motion in the thickness direction and the particledisplacement distribution patterns are obtained for disks whose thickness-diameter ratios are less than0.45.Correction curves for thickness effect on fundamental frequencies are given.Curves showing.the effect of Poisson ratio on the relation between the second harmonic-fundamental ratio and thethickness-diameter ratio are also given. In the numerical calculations,piezoelectric ptoperties of the ceramic disks are fully taken intoconsideration and no restrictions are set for the dimensions of the disks.Experimental results agreewell with those obtained by calculation.     

A STATISTICAL THEORY FOR THE BIO-PHOTON EMISSION OF THE LIVING SYSTEMS

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THE IMPACT OF SDI ON THE ARMS RACE——A SOLUTION OF GAME THEORY

The impact of SDT on arms race has been discussed in a model which includes intercontinental ballistic missiles, anti-FCBM satellites and anti-satellite weapons for U.S. and former Soviet Union. It is assumed that each side of U. S. and former Soviet Union wants to reach the biggest retaliatory capability for given expenditure. This problem is considered as a two-person game and the optimal configurations of the three kinds of weapons for both sides is calculated under different conditions. The results show that the SDI can not lead to the transition from an offensive mode to a defensive mode and can not also offer an effective protection against the threat of ICBMs.     

PHOTON STATISTICS OF THE MICROMASER WITH ULTRA COLD Λ-TYPE THREE-LEVEL ATOMS

We have established the master equation for the micromaser with the ultra-cold Λ-type three-level atoms and studied the photon statistics of the micromaser field. We find that as the atoms become colder,the change of the mean photon-number and the normalized standerd deviation become more regular, and their resonance peaks become sharper. For zero-temperature cavity,there are some regins in which the photon statistics are sub-Poissonian.With the increase of the cavity temperature,both the mean photon-number and the normalized standard deviation increase. When the cavity temperature is high enough, the sub-Poissonian property may disappear.     

ON THE APPLICATION OF A GENERALIZED VERSION OF THE DRESSING METHOD TO THE INTEGRATION OF VARIABLE COEFFICIENT N-COUPLED NONLINEAR SCHRÖDINGER EQUATION

N-coupled nonlinear Schrödinger (NLS) equations have been proposed to describe N-pulse simultaneous propagation in optical fibers. When the fiber is nonuniform, N-coupled variable-coefficient NLS equations can arise. In this paper, a family of N-coupled integrable variable-coefficient NLS equations are studied by using a generalized version of the dressing method. We first extend the dressing method to the versions with (N + 1) × (N + 1) operators and (2N + 1) × (2N + 1) operators. Then, we obtain three types of N-coupled variable-coefficient equations (N-coupled NLS equations, N-coupled Hirota equations and N-coupled high-order NLS equations). Then, the compatibility conditions are given, which insure that these equations are integrable. Finally, the explicit solutions of the new integrable equations are obtained.     

PHOTON STATISTICS OF THE MICROMASER WITH ULTRA COLD Λ-TYPE THREE-LEVEL ATOMS

We have established the master equation for the micromaser with the ultra-cold Λ-type three-level atoms and studied the photon statistics of the micromaser field. We find that as the atoms become colder,the change of the mean photon-number and the normalized standerd deviation become more regular, and their resonance peaks become sharper. For zero-temperature cavity,there are some regins in which the photon statistics are sub-Poissonian.With the increase of the cavity temperature,both the mean photon-number and the normalized standard deviation increase. When the cavity temperature is high enough, the sub-Poissonian property may disappear.     

REALIZATION OF THE WAVE-PACKET-COLLAPSE —A VIEWPOINT TO THE QUANTUM MEASUREMENT THEORY

An interpretion of the wave-packet-collapse (WPC) in the system of quantum mechanics is given. We find a connection between the WPC and the limitation to the measurement precision determined by the quantum fluctuation. A simple and explicit relation about them is obtained.     

STUDY OF THE CO LASER-CATALYZED PHOTOCHEMICAL REACTION OF UF_6 WITH HCI AND ITS ISOTOPIC SELECTIVITY

The kinetios of UF_6 HCl reaction and the isotopic seleotivity for thisprocess were investigated by using an intracavity CO laser system. It was found thatunder the resonant CO laser irradiation, the laser-catalyzed reaction rate was inereasedremarkably and a good selectivity was achieved. The uranium isotope separation factorobtained by this photochemioal process was about 1.2.     

REALIZATION OF THE WAVE-PACKET-COLLAPSE —A VIEWPOINT TO THE QUANTUM MEASUREMENT THEORY

An interpretion of the wave-packet-collapse (WPC) in the system of quantum mechanics is given. We find a connection between the WPC and the limitation to the measurement precision determined by the quantum fluctuation. A simple and explicit relation about them is obtained.