Moist Potential Vorticity Anomaly with Heat and Mass Forcings in Torrential Rain Systems

The moist potential vorticity (MPV) equation is derived from complete atmospheric dynamic equations with both heat and mass forcings,with which the impermeability theorem of the “MPV substance” is proven.It is clarified that both heat and mass forcings induced by the intensive precipitation in torrential rain systems can lead to the MPV anomaly.The MPV substance anomaly is a dynamical tracer for tracking a torrential rain system.     

Zipf’s law and distribution of population in Indian cities

The Zipf’s law is studied here in the context of size distribution of Indian cities and the power law exponent is estimated. We have used the data from the Indian censuses of 1981,1991 and 2001. The analysis shows that the population distribution in Indian cities do follow a power law similar to the ones found in other countries. The scaling exponent are found to be 2.15 ± 0.01 for 1981, 2.11 ± 0.01 for 1991 and 2.05 ± 0.02 for 2001 from the linear fit. We have also estimated the scaling exponent from the maximum likelihood estimator technique which is found to be 2.04 ±.07 for the year 2001.     

Multiresolution processing for source detection and localization

The conventional BF/MFP (beamforming/matched field processing) or BF/MFP based on subspace axe traditional array signal processing methods for source‘s detection and location, they axe all belonging to singe-resolution processing. In fact, the array signal has multiresolution structure, which is worthy of exploiture and utilization to enhance the ability of detection and location, especially to improve the robustness for BF/MFP. The time-space multiresolution modeling of multipath transmitted wave and the corresponding multiresolution focused processing axe investigated, and it is shown from the analysis of actual sea-trial data that the performance of MFP can be improved.     

Simulation for Astroparticle Experiments and Planetary Explorations：Tools and Applications

We present a set of tools and general-pupose applications for the simulation of astrophysics and astroparticle experiments,concerning both physics and radiation background studies.They addrss the speific requirements of various typical astroparticle detectors:new-generation X-and γ-ray detectors on satellites,underground detectors for astroparticle experiments and solar system explorations.     

Activation and Afterheat Calculation Analysis for TBM

Safety considerations of TBM are part of the design process to ensure that the TBM do not adversely affect the safety of ITER. So accurate calculations of all radioactivity and potential harmfulness are very important for designing of device, selecting of blanket and shield material, analyzing of the safety and environment, disposing of nuclear waste and operation of the reactor.     

Stabilization and Consistency for Subtracted and Unsubtracted QCD Sum Rules for 0^＋＋ Scalar Glueball

Based on a semi-classical expansion for quantum chromodynamics in the instanton liquid background, the correlation function of the 0^＋＋ scalar glueball current is calculated. Besides the pure classical and quantum contributions, the contributions arising from the interactions between the classical instanton fields and quantum gluon ones come into play. It turns out that the latter contributions have a great role not only in making the stabilization of the subtracted and unsubtracted Laplace-transformed QCD sum rules for 0^＋＋ scalar glueball, but also in bring back the consistency between the two related sum rules, or equivalently between the QCD asymptotic expression and low energy theorem. The result for the scalar glueball mass is predicted to be mG= 1.35 GeV.     

α particle preformation and shell effect for heavy and superheavy nuclei

The α particle preformation factor is extracted within a generalized liquid drop model for Z = 84-92 isotopes and N = 126,128,152,162,176,184 isotones.The calculated results show clearly that the shell effects play a key role in α particle preformation.The closer the proton and neutron numbers are to the magic numbers,the more difficult the formation of the α cluster inside the mother nucleus is.The preformation factors of the isotopes reflect that N = 126 is a magic number for Po,Rn,Ra,and Th isotopes,but for U isotopes the weakening of the influence of the N =126 shell closure is evident.The trend of the factors for N = 126 and N = 128 isotones also support this conclusion.We extend the calculations for N = 152,162,176,184 isotones to explore the magic numbers for heavy and superheavy nuclei,which are probably present near Z = 108 to N = 152,162 isotones and Z = 116 to N = 176,184 isotones.The results also show that another subshell closure may exist after Z = 124 in the superheavy nuclei.This is useful for future experiments.     

Hyperspherical Calculations on Electron Affinity and Geometry for Li^- and Na^-

Using a model potential to describe the interaction between the core and the valence electron, we perform hyperspherical calculations for electron affinity and geometry of the weakly bound Li^- and Na^- systems. In our calculation, channel functions are expanded in terms of B-splines. Using the special properties of B-splines, we make the knot distributions more precisely, characterizing the behaviour of channel functions. This improves the convergence greatly. Our results are in good agreement with the other theoretical and experimental values.     

Compact and efficient modulators for 100 Gb/s ETDM for telecom and interconnect applications

State of the art and prospects regarding semiconductor compact modulators and transmitters for on–off keying and more advanced modulations formats for output bitrates of 100 Gb/s and above are discussed. The implementation of a monolithically integrated transmitter comprising laser and light-intensity modulator is described and the prospects for a fully integrated transmitter for more advanced modulation formats elucidated, all for 100 Gb/s output bitrate     

Competition between α-decay and β-decay for heavy and superheavy nuclei

In this work, the β-stable region for Z 90 is proposed based on a successful binding energy formula.The calculated β-stable nuclei in the β-stable region are in good agreement with the ones obtained by Mo¨ller et al. The half-lives of the nuclei close to the β-stable region are calculated and the competition between α-decay andβ-decay is systematically investigated. The calculated half-lives and the suggested decay modes are well in line with the experimental results. The decay modes are mostly β--decay above the β-stable region. Especially for Z 111,all the decay modes are β--decay. Regarding the nuclei above the β-stable region, α-decay and β--decay(α+β-)can occur simultaneously when Z 112. This is a very interesting phenomenon. The competition between α-decay and β-decay is very complex and drastic below the β-stable region. The predictions for half-lives and decay modes of the nuclei with Z =107–110 are presented in detail.     

Petrov–Galerkin and discontinuous-Galerkin methods for time-domain and frequency-domain electromagnetic simulations

Finite-element discretizations for Maxwell’s first-order curl equations in both the time domain and frequency domain are developed. Petrov–Galerkin and discontinuous-Galerkin formulations are compared using higher-order basis functions. Verification cases are run to examine the accuracy of the algorithms on problems with exact solutions. Comparisons with other, well accepted, methodologies are also considered for problems for which exact solutions do not exist. Effects of several parameters, including spatial and temporal refinement, are also examined and the relative efficiency of each scheme is discussed. By considering test cases previously considered by other researchers, it is also demonstrated that the algorithms do not exhibit spurious solutions. Finally, three-dimensional results are compared with test results for a rectangular waveguide for which experimental data has been obtained with the explicit purpose of code-validation. The ability to predict changes in scattering parameters caused by variations in geometric and material properties are examined and it is demonstrated that the algorithms predict these changes with good accuracy.     

Poincaré's theorem and unitary transformations for classical and quantum systems

Poincaré's celebrated theorem on the nonexistence of analytical invariants of motion is extended to the case of a continuous spectrum to deal with large classical and quantum systems. It is shown that Poincaré's theorem applies to situations where there exist continuous sets of resonances. This condition is equivalent to the nonvanishing of the asymptotic collision operator as defined in modern kinetic theory. Typical examples are systems presenting relaxation processes or exhibiting unstable quantum levels. As the result of Poincaré's theorem, the unitary transformation, leading to a cyclic Hamiltonian in classical mechanics or to the diagonalization of the Hamiltonian operator in quantum mechanics, diverges. We obtain therefore a dynamical classification of large classical or quantum systems. This is of special interest for quantum systems as, historically, quantum mechanics has been formulated following closely the patterns of classical integrable systems. The well known results of Friedrichs concerning the coupling of discrete states with a continuum are recovered. However, the role of the collision operator suggests new ways of eliminating the divergence in the unitary transformation theory.     

Theoretical study of spectral parameters for the γ and β band systems of NO for atmosphere and high temperature

Highly correlated ab initio calculations were performed for accurate determination of γ (A²Σ⁺-X²П) and β (B²П-X²П) band systems of NO molecule. Highly accurate multi-reference configuration interaction approach was used to investigate the potential energy curves (PECs) and transition dipole moment curves. We correctly and fully described their diffuse wave functions by the obvious balance between the valence and Rydberg character of the X²П, A²Σ⁺, B²П, C²П and D²Σ⁺ states. The PECs of the three states (X²П, A²Σ⁺ and B²П) by using the aug-cc-pV5Z (aV5Z) basis set for N and O atoms agreed well with the Rydberg–Klein–Rees potential. Moreover, the Einstein A coefficients were calculated to predict the lifetimes, where the vibrational bands included v′ = 0–8, v″ = 0–29 for γ system and v′ = 0–11, v″ = 0–31 for β system. The spectral line intensities of the γ and β systems for atmosphere and high temperature were provided.     

Optimization and Comparison for Different Raman Amplifier Configurations

Gain spectra and corresponding optical signM-to-noise ratio (OSNR) for bi-directionM multi-pump Raman amplifiers are optimized and compared. Numerical results exhibit that, for optimizing hi-directional multi-pump configurations, there are multiple global maxima for signal gain spectra, and different hi-directional pump cases have different gain ripple and noise performance. Bi-directionally pumping schemes with suitable pump spectra can obviously decrease the gain ripple and equalize the OSNR tilt in comparison with pure backward pumping schemes.     

Periodic Bifurcation and Soliton Deflexion for Kadomtsev-Petviashvili Equation

The spatial-temporal bifurcation for Kadomtsev-Petviashvili （KP） equations is considered. Exact two-soliton solution and doubly periodic solution to the KP-I equation, and two classes of periodic soliton solutions in different directions to KP-Ⅱ are obtained using the bilinear form, homoclinic test technique and temporal and 1 spatial transformation method, respectively. The equilibrium solution uo =-1/6, a unique spatial-temporal bifurcation which is periodic bifurcation for KP-I and deflexion of soliton for KP-Ⅱ, is investigated.     

Data Collection and Processing for ARGO Yanbajing Experiment

ARGO－YBJ，a Chinese-Italian Collaboration,is going to finish the first step of the installation of this cosmic ray telescope consisting in a single layer of RPCs,placed at 4300m.elevation,in Tibet,The detector will provide a detailed space-time picture of the showers front,initiated by primaries of energies in the range 10GeV-500 TeV.The data taking will start at the beginning of 2002 with a fraction of the detector installed.will be upgraded two times,being completed at the end of 2003,In this paper we briefly describe the dataflow,the trigger organization,the three operational steps in data taking and the computing model to process the data.the need of remote monitoring of the experiment will be touched upon.The processing power for the raw data reconstruction and for the Monte Carlo simulation is reported.     

Simple and robust digital holography for high-resolution imaging

Based on the point spread function of holographic system,the lateral resolution of digital holographic imaging system without any pre-magnification is studied.The expression of resolution limitation of holo- graphic imaging system is thus presented.We investigate the possibilities to improve the lateral resolution. The simple experimental setup with an off-axis arrangement is built.By using a U.S.Air Force(USAF) test target as microscopic object,the recorded holograms are reconstructed digitally based on the principle of Fresnel diffraction.The lateral resolution of 2.76μm without any pre-magnifieation is demonstrated experimentally,which matches the theoretical prediction well.     

Renormalization and Periodic Orbits¶for Hamiltonian Flows

We consider a renormalization group transformation for analytic Hamiltonians in two or more dimensions, and use this transformation to construct invariant tori, as well as sequences of periodic orbits with rotation vectors approaching that of the invariant torus. The construction of periodic and quasiperiodic orbits is limited to near-integrable Hamiltonians. But as a first step toward a non-perturbative analysis, we extend the domain of to include any Hamiltonian for which a certain non-resonance condition holds. Received: 5 October 1999 / Accepted: 2 February 2000