A New Exactly Solvable Inflation Model and its Power Spectrum

We present a new exactly solvable inflation model in which inflation can stop automatically,and in the approximately de sitter limit,we give its power spectrum which can be tested in the future observations of cosmic microwave background anisotropy.     

Topological Properties and Transition Features Generated by a New Hybrid Preferential Model

A new hybrid preferential model （HPM） is proposed for generating both scale-free and small world properties. The topological transition features in the HPM from random preferential attachment to deterministic preferential attachment are investigated. It is found that the exponents γ of the power law are very sensitive to the hybrid ratio （d/r） of determination to random attachment, and γ increases as the ratio d/r increases. It is also found that there exists a threshold at d/r = 1/1, beyond which γ increases rapidly and can tend to infinity if there is no random preferential attachment （r= 0）, which implies that the power law scaling disappears completely.Moreover, it is also found that when the ratio d/r increases, the average path length L is decreased, while the average clustering coefficient C is increased. Compared to the BA model and random graph, the new HPM has both the smallest L and the biggest C, which is consistent with most real-world growing networks.     

A New Laser Frequency-stabilizing and Frequency-locking System

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A New Scheme of Entanglement Swapping and Disentanglement

We consider three two-level atoms (A, B, and C) initially in the W entanglement state, then one of them, C, is injected into a high-Q cavity to make resonant interaction to entangle with the other two atoms A and 13 that are far away from the cavity. The entanglement swapping or disentanglement can be realized by carrying out measurements on C and selecting appropriate interaction time of C with the coherent field.     

New Criteria for Self-Adjointness and its Application to Dirac–Maxwell Hamiltonian

We present a new theorem concerning a sufficient condition for a symmetric operator acting in a complex Hilbert space to be essentially self-adjoint. By applying the theorem, we prove that the Dirac–Maxwell Hamiltonian, which describes a quantum system of a Dirac particle and a radiation field minimally interacting with each other, is essentially self-adjoint. Our theorem covers the case where the Dirac particle is in the Coulomb-type potential.     

HL-2A Control System and its Discharge Management

HL-2A is a divertor tokamak with noncircular plasma cross-section, it can operate in single-null or double-null plasma discharges.The toroidal and poloidal coils, vacuum vessel and supporting structure of HL-2A come from the former ASDEX, Germany.     

A subalgebra of loop algebra A2^～ and its applications

A subalgebra of loop algebra A2^～ and its expanding loop algebra G^- are constructed. It follows that both resulting integrable Hamiltonian hierarchies are obtained. As a reduction case of the first hierarchy, a generalized nonlinear coupled Schroedinger equation, the standard heat-conduction and a formalism of the well known Ablowitz, Kaup, Newell and Segur hierarchy are given, respectively. As a reduction case of the second hierarchy, the nonlinear Schroedinger and modified Korteweg de Vries hierarchy and a new integrable system are presented. Especially, a coupled generalized Burgers equation is generated.     

A New （2＋1）-Dimensional KdV Equation and Its Localized Structures

A new （2＋1）-dimensional KdV equation is constructed by using Lax pair generating technique. Exact solutions of the new equation are studied by means of the singular manifold method. Bgcklund transformation in terms of the singular manifold is obtained. And localized structures are also investigated.     

A New Modified Extended Tanh-Function Method and Its Application

In this paper, a new modified extended tanh-function method is presented for constructing soliton-like,periodic form solutions of nonlinear evolution equation (NEEs). This method is more powerful than the extended tanhfunction method [Phys. Lett. A277 (2000) 212] and the modified extended tanh-function method [Phys. Left. A285 (2001) 355]. Abundant new solutions of two physically important NEEs are obtained by using this method and symbolic computation system Maple.     

New region of interest image coding and its applications for remote sensing image

A new region of interest (ROI) coding called partial multiply bitplane alternating shift (PMBAShift) is presented in this paper. In PMBASluft, the partial most significant bitplanes of ROI are shifted up and no overlap with any bitplane of background (BG). The most significant bitplanes of BG and general significant bitplanes of ROI coefficients are shifted up by bitplane-by-bitplane alternating scaling. Finally, the least significant bitplanes of ROI and the general significant bitplanes of BG are obtained in the original position and the least significant bitplanes of BG coefficients are shifted down and no overlap with any bitplane. The new method not only retains advantages of maximum shift (Maxshift) method, but also efficiently compresses multiple ROIs according to different degrees of interest without any shape information.     

Axisymmetric form of Kármán-Howarth equation and its limiting forms

Kinematics and dynamics of homogeneous axisymmetric turbulence have been derived with the assumption that the properties of the turbulence are invariant with respect to rotation about a preferred direction . In particular, the “axisymmetric" equivalent of Karman-Howarth “isotropic" equation is derived using Lindborg's representation of the two-point correlation tensors of homogeneous axisymmetric turbulence. When the more constraining assumption of isotropy is made, this equation reduces to the well-known Karman-Howarth equation. There are two interesting limiting forms of the axisymmetric Karman-Howarth equation: the axisymmetric form of the energy balance equation and the axisymmetric form of the vorticity balance equation. Received 1 July 1999 and Received in final form 9 November 1999     

Tunable two-wavelength lasing of Ti: Al_2O_3 and its two-wave mixing in β-BaB_2O_4

A tunable Ti: sapphire laser with a symmetric two-channel dispersive resonator operated simultaneously at two wavelengths was obtained. The delay between λ_1 and λ_2 pulses did not exceed a few nanosecond. Independent tunable range of each output wavelength is 720-820nm, and the maximum wavelength difference was about 55nm. The competition and connectivity between two waves have been observed. The frequency suming and doubling of the two waves generated in BBO were also obtained.     

A novel coupled quantum well structure and its excellent electro-optical properties

A novel InGaAs/InAlAs coupled quantum well structure is proposed for large field-induced refractive index change with low absorption loss. In the case of low applied electric field of 15 kV/cm and low absorption loss (±≤ 100 cm-1), a large field-induced refractive index change (for transverse electric (TE) mode, △n = 0.012; for transverse magnetic (TM) mode, △n = 0.0126) is obtained in the structure at the operation wavelength of 1.55 μm. The value is larger by over one order of magnitude than that in a rectangular quantum well. The result is very attractive for semiconductor optical switching devices.     

A Generalization of the Goldberg–Sachs theorem and its consequences

The Goldberg–Sachs theorem is generalized for all four-dimensional manifolds endowed with torsion-free connection compatible with the metric, the treatment includes all signatures as well as complex manifolds. It is shown that when the Weyl tensor is algebraically special severe geometric restrictions are imposed. In particular it is demonstrated that the simple self-dual eigenbivectors of the Weyl tensor generate integrable isotropic planes. Another result obtained here is that if the self-dual part of the Weyl tensor vanishes in a Ricci-flat manifold of (2,2) signature the manifold must be Calabi–Yau or symplectic and admits a solution for the source-free Einstein–Maxwell equations.     

A stochastic discrete model of tissue and its ultrasonic backscattering coefficient

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