Table of Content

20 May 2001, Volume 37 Issue 3

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To Embed Multiple Watermarks Simultaneously

HUA Xiansheng,SHI Qingyun

2001, 37(3):  305-314. 

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It is studied that the problems in embedding multiple watermarks simultaneously, and proposed an image watermarking scheme which embedded fragile and robust watermarks at the same time. This algorithm, which is based on integer wavelet transform, is public watermarking scheme, both of the two kinds of watermarks can be retrieved without knowing the original image. For retrieving the watermarks, the author proposed a “credible bit” method, which could enhance the robustness of the watermarks. Meanwhile, besides telling you whether an image has been tampered, the fragile watermark could as well, reflect the distortion status in both spatial and frequency domain of the image.

A Law of the Iterated Logarithm for the Heavily Trimmed Sums

WANG Fang,CHENG Shihong

2001, 37(3):  289-293. 

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Let{X_n, n≥1} be a sequence of i.i.d. random variables with common d.f.F(x). X_{1, n}≤…≤X_{n, n}}are its order statistics. Qis the quantile function of F. It is shown that for any underlying distribution function F, the LIL for the heavily trimmed sums remains true, as long as λ and 1-λare continuity points of Q and σ(λ)>0. Moreover, a strong approximation result is obtained in this case.

Self-orthogonal Ideal in Group Algebras

QIU Weisheng

2001, 37(3):  294-296. 

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It is proved that every nonzero ideal in a finite-dimensional semi-simple algebra over a field is generated by an unique central idempotent. Applying this result it is proved that for arbitrary finite group G and arbitrary field Fwhich characteristic does not divide |G|, the only ideal in the group algebra F[G] that is both self-orthogonal and reversible is the zero ideal.

Pseudo Almost Periodic Solutions of Neutral Delay Differential Equations with Piecewise Constant Arguments

PIAO Daxiong

2001, 37(3):  297-304. 

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By constructing a pseudo almost periodic solution sequence for a relevant difference equation, we investigated the existence and uniqueness of pseudo almost periodic solution of neutral delay differential equation with piece-wise constant argumentsd/dt(y(t)+py(t-1))=a₀ y([t])+a₁y([t-1])+F(t, y(t), y([t])).

A New Fast Search Algorithm for Block Motion Estimation

WANG Minghui,PENG Lizhong

2001, 37(3):  315-322. 

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Block motion estimation using full search is computationally intensive, many fast algorithm have proposed to reduce the computation at the expense of less accuracy of motion estimation. In this paper, we present a new fast and efficient search algorithm for block motion estimation. The proposed algorithm is based on the ideas of predicted starting search point, subsampled block distortion measure, center-biased distribution of motion vector, multiple-candidate diamond search. From the experimental results, the proposed algorithm is superior to many other well-known fast algorithms in both quality performance and computational complexity.

IQC's Theory in the Time Domain and Its Application

YU Xuegang,HUANG Lin

2001, 37(3):  323-329. 

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The stability of the feedback interconnection of a linear stable system and a bounded perturbation is studied in time domain in this paper. It's shown how a complex system can be characterized by integral quadratic constraints(IQC's). And the IQC's theory in the time domain is given. For such model, A sufficient condition for the stability of the feedback interconnection is obtained, in some cases, this condition is also necessary. As the applications of the result in this paper, the problem of absolute stability is considered, then the time-varying circle criterion and other stability criteria are given.

Wind Tunnel Experiment on the Model of the Chinese National Grand Theatre

YAN Dachun,SUN Zhili,HUANG Sheng,DING Wuquan,CHEN Mingfu,LIN Rongsheng,QIU Panxiang,LI Hong,LIU Hanlin

2001, 37(3):  330-335. 

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The main results of the wind tunnel experiment on the 1/200 model of the Chinese National Grand Theatre were introduced. At first, the wind pressure distributions of its semi-ellipsoidal surface in an atmospheric boundary layer flow were simulated, and the effect of the surface roughness was researched. The results indicated a reasonable regularity of its wind loading in various wind directions. On the problem of the environmental influence, it demonstrated that there existed a great effect for the pressure distribution of the Great Theatre when the Grand Hall is at east.

Density Functional Theory Studies of the Core Excited Energies of HgBa₂CaCu₂O_6+δ

LU Jin,ZHANG Shuang,ZHANG Liyuan,LI Jun,ZHANG Xinwei,ZHAO Xiangeng

2001, 37(3):  336-339. 

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Relativistic spinpolarized local density functional calculations have been performed for HgBa₂CaCu₂O_6+δ. The calculated core excited energies essentially agree with the XPS spectra. The spinorbit splittings are especially in satisfactory agreement with the observed ones.

Model of Spread F Longitudinal Effect

ZHANG Tianhua,XIAO Zuo

2001, 37(3):  348-352. 

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A new model was presented in a three dimensional geographic coodinate system to describe the linear growth of R-T instability so that the effects of magnetic inclination and declination were taken into accont. It is an generalization of former theories from equatorial to mid-latitude regions. From this model one can see the influence of magnetic strength, inclination and declination. Due to the magnetic effects, the occurrence rate of the instability is not symmetric in longitudes even at the magnetic equator. Some occurrence peaks or valleys will appear in certain places around the world.

Diagnostic Analyses on Blocking System of A Severe Cold Case

Narentuya,SHAO Mingxuan,ZHANG Nao

2001, 37(3):  340-347. 

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The quasi-geostrophic process was diagnosed for a case of severe cold air breakout under the blocking situation during 16-18 March of 1998. The attention was focused on the relationship between the surface anticyclone and 500hPa blocking high. The results indicate that the cold outbreak is associated with the adjustment of blocking situation in the Ural Area, i.e. the collapsing and rebuilding of the Ural Mountain blocking high. The temperature advections in the lower troposphere shown that the polar cold air invading from the northwest caused the Ural blocking high collapsed, and a new ridge developed rapidly was due to the warm advection on the southwestern side which led to the Ural blocking high rebuilt. In addition, the distribution of the vertical motion on 700hPa shown that the surface high splitting was related to the considerable upward motion located on the southeastern part of surface high.

13.5 GHz f_T SiGe Heterojunction Bipolar Transistor Fabricated by Planar Technology

JIA Lin,NI Xuewen,MO Bangxian,GUAN Xudong,ZHANG Lu,NING Baojun,HAN Ruqi,LI Yongkang,ZHOU Junming

2001, 37(3):  353-358. 

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A planar SiGe heterojunction bipolar transistor was fabricated using polysilicon emitter technology and SiGe base grown by Molecular Beam Epitaxy (MBE). The SiGe HBT(S_e=3μm×8μm) has a current gain β of 30 to 50, an emitter-collector breakdown voltage BV_CEO of 5V, the maximum cutoff frequency f_T of 13.5GHz at room temperature.

Study on Vacuum Fabrication of Ag-O-Cs Thin Films with Internal Field-assisted Structure

ZHANG Qifeng,LIU Weimin,XUE Zengquan,WU Jinlei

2001, 37(3):  359-364. 

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With the aid of baffle movement, a technique named masking pretreatment and the method of vacuum deposition have been used to fabricate the Ag-O-Cs photoemissive thin films with internal field-assisted structure for the first time. The internal field-assisted photoemission characteristics of Ag-O-Cs thin films show that the photoelectric sensitivity is increased when the internal electric field is applied to the thin films, which indicates that the electric field has been effectively provided to the thin films by the above-mentioned internal field-assisted structure. Such an enhanced photoemission is attributed to the variations in energy-band structure of Ag-O-Cs thin films, and which are considered to induce the lower-energy electrons to participate in the photoemission.

Study on Noisy Speech Recognition Methods

WU Shuzhen,FENG Chenglin,HUANG Xinyu

2001, 37(3):  365-370. 

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There are difficulties in noisy speech recognition, especially low signal-to-noise rations are more difficult. This paper describes briefly six methods for speaker-dependent noisy speech recognition(isolated words). They are LPC prediction error method, one-side auto- correlation sequence LPC, acoustic front end processing, canonical correlation based on compensation method, combination of features method and increase of poles method. The experimental results show that all the six techniques can improve effectively noisy speech recognition, and the best noisy speech recognition rate is above 80%(when SNR=0dB).

On the Importance of Components of the MFCC in Speech and Speaker Recognition

ZHEN Bin,WU Xihong,LIU Zhimin,CHI Huisheng

2001, 37(3):  371-378. 

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The analysis of the relative importance of components of MFCC for both speech recognition and speaker recognition using DTW recognizer in various noise environments are given. For English digit and under the Euclidean distance definition, the experiment results show cepstral components from C₂ to C₁₆contain the most useful speaker information, while C₀ and C₁ are usually harm to speaker recognition. Cepstral terms from C₁ to C₁₂ are found to contain the most useful speech information. In both tasks, the additive noise decreases the relative importance of low MFCC terms faster than that of the middle and high MFCC terms, and the decrement depends on the speech SNR. The channel distortion will deteriorate low terms more than the middle and high MFCC terms in both tasks, also.

The Regression Analysis Study on Velocity and Porisity, and Clay Content of Rocks

SHI Ge,YANG Dongquan

2001, 37(3):  379-384. 

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The typical samples with different lithological characters are collected from two wells of representative reservoir consisting of sandstone and conglomerate of positive rhythm. Compressional and shear wave velocities, porosity, and clay content are measured in two states fully saturated with water(S_w=1) and gas(S_w=0), respectively. The regression analysis shows that the velocities are liner relationship related to porosity and clay content. Using such regression formula to sonic logging data indicates that the coefficients of the formula should be determined by statistical method about specific area, instead of fixed values.

PEGs Abundance Patterns and Its Implications of Carboniferous Volcano Zone to South and North of Turpan-Hami Basin, Xinjiang Uigur Autonomous Region

GAO Honglin,MU Zhiguo,JIN Xindi,ZHU Heping

2001, 37(3):  385-393. 

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The PGEs abundance patterns of residual mantle rock with a peleo-subduction background is characterized by Pd, Pt depletion and Ir, Ru relatively enrichment, while the basalt and basic dyke by the processing of partial melt in the same background take an opposite feature of Pd, Pt enrichment and Ir, Ru depletion. the existence of fluid in the subduction zone increases the degree of partial melt on the one hand, and on the other, activates the activity of Pd, Pt compare to Ir, Ru, and thus reduces the Pd/Ir and Pt/Ru in residual mantle rock. The PGEs patterns for basalt and basic dyke from two Carboniferous volcano zones to south(Qoltag)and north(Bogda)Turpan-Hami basin, XinJing Uigur Autonomous Region, take a shape of gentle positive inclined curve with lower Pt and Pd differentiation and lower Σ PGEs. All these features are obviously different from that of basic dyke and basalt from typical ophiolite and therefore the author believe that their fluid-rich paleo-subduction zone environment can be ruled out.

A Brief Study on the Relationships between Earthquakes and Active Faults

LI Shude

2001, 37(3):  394-399. 

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Shallow structure earthquakes are always concurrent with fault activities. Evidence testifies that earthquakes often occurred densely near the place where the faults exist. There is an intimate relationship between earthquakes and active faults. So in analyzing the danger coefficient of earthquakes, it is very important to ascertain the locations and scale of earthquakes that will occur possibly in the future.

The Study of City Soil and Water Loss and It's Tri-dimensional System

YUAN Renmao,YANG Xiaoyan,LI Shude

2001, 37(3):  400-406. 

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Soil and water loss of city includes soil loss and water loss. With the short of water resource more and more serious, as do soil loss, water loss of city also affects the development of city. Soil and water loss of city occurs not only on the earth surface, but also under the ground. The type of soil and water loss is diverse. At the same time, the characters of city soil and water loss are different in different regions.

Statistical Analysis of the River Networks on Neotectonic Divergency of East and West Parts in Jiaodong Peninsula

DU Guoyun

2001, 37(3):  407-412. 

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For river networks, its growth subjects are notably influenced by climate, geotectonic movement, and mankind actions. And its character certainly reflects the different conditions of geotectonic movement. Statistical analysis of some characters of the river networks including the river direction's, the geometric fractal of main river's and the river network density's in Jiaodong peninsula showed that the river networks respond obviously to the neotectonic movement. The area is mainly divided into the west part and the east part by Taocun-Dongdoushan fault during neotectonic movement.

Research on Web Publishing of Spatial Information

YANG Chaowei,LI Qi

2001, 37(3):  413-420. 

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A system review and research on the web publishing of spatial information are made, according to the status and character of Internet and spatial information. Problems of publishing architecture and respective technical are given out and solved, the spatial information web publishing prototype-WebGIS is implemented according to it. The future of web publishing of spatial information is also discussed. The first section gives the background of web publishing of spatial information. The second section is dedicated to the architecture of it and this section is followed by the techniques used in constructing the web publishing system of spatial information with a prototype of it, WebGIS is implemented to display how to build a web publishing system of spatial information. In section 4 some future trends about web publishing of spatial information are discussed in detail.

Artificial Neuron Network and Its Application to Financial Forecasting

XIE Zhongjie,WONG Heung,IP Wai-Cheung,LIU Yali

2001, 37(3):  421-425. 

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The main purpose of this paper is to investigate the application of the neuron network (NN) for the daily exchange rate forecasting. Generalized Cross Validation (GCV) is introduced to determine the number of nodes of the hidden layer, several well known time series forecasting methods are also compared with the NN method in this paper.

A Exploration about General Information Theory

LUO Xianhan

2001, 37(3):  426-432. 

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Based on the researches of ancient world outlook and modern cosmology, it presented a new theory of general information, introduced the modelling method drawn general information from the narrow information. Cosmic gene is the general information carried by the particles, decided mostly by physical canstants of the particles and related physicl laws, and may be discerned easily. Life gene is the general information carried by four kinds of nucleotide, decided mostly by characterstic parameters of these nucleotides and related natural laws, and need continuing researches. Finaly, the devlopments of cosmos and life obey all that the law of the unity of opposites.

A Exploration about General Information Theory

LUO Xianhan

2001, 37(3):  426-432. 

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Based on the researches of ancient world outlook and modern cosmology, it presented a new theory of general information, introduced the modelling method drawn general information from the narrow information. Cosmic gene is the general information carried by the particles, decided mostly by physical canstants of the particles and related physicl laws, and may be discerned easily. Life gene is the general information carried by four kinds of nucleotide, decided mostly by characterstic parameters of these nucleotides and related natural laws, and need continuing researches. Finaly, the devlopments of cosmos and life obey all that the law of the unity of opposites.