Please wait a minute...
Information

Journal of Jilin University Science Edition
ISSN 1671-5489
CN 22-1340/O
主 任:韩啸
编 辑:赵立芹 王健 单凝 李琦
电 话:0431-88499428
E-mail:sejuj@jlu.edu.cn
地 址:长春市南湖大路5372号
    (130012)
WeChat

WeChat: JLDXXBLXB
随时查询稿件状态
获取最新学术动态
Table of Content
26 March 2009, Volume 47 Issue 02
数学
Existence and Uniqueness of Global Solutions to a Class ofQuasilinear Degenerate Parabolic Systems
MA Qi, GAO Wenjie
J4. 2009, 47 (02):  159-164. 
Abstract ( 1326 )   PDF (344KB) ( 486 )  
This paper aims at a weak coupling evolution p-Laplacian system with the first initial and boundary value conditions. Under appropriate hypotheses, the method of regularization is used to construct a sequence of solutions with the help of monotone iteration technique and the solution to the regularized system can be found. Then the existence of solutions to the evolution p-Laplacian system is obtained by a standard limiting process. Finally, the uniqueness of the solution can be proven by integral method.
Related Articles | Metrics
Finite Volume Element Methods of Fifthorder Hermite Typefor Twopoint Boundary Value Problems
TIAN Wanfu, LV Junliang, WANG Yan he, LI Yonghai
J4. 2009, 47 (02):  165-173. 
Abstract ( 1407 )   PDF (460KB) ( 448 )  
We constructed a finite volume scheme of fifth order Hermite type with high accuracy for twopoint boundary value problems, choosing trial and test spaces as the fifthorder finite element space of Hermite type and the piecewise linear function space respectively. We didn’t use higher derivatives as interpolation conditions, which is the same as the thirdorder finite element of Hermite type, but the scheme obtained had higher accuracy. The optimal convergence rates in H-1 and L-2 norms are proved, and the convergence order in L-2 norm is one order higher than that in H-1 norm. The numerical examples confirm the theoretical results.
Related Articles | Metrics
Separating Element Computation for the Rational UnivariateRepresentation with Short Coefficients inZerodimensional Algebraic Varieties
TAN Chang, ZHANG Shugong
J4. 2009, 47 (02):  174-178. 
Abstract ( 1532 )   PDF (487KB) ( 352 )  
Since the separable element algorithm of the rational univariate representation (RUR) for solving zerodimensional systems presented by Rouillier makes the size of the coefficients in this representation too long, an improved algorithm for finding separating elements is presented in this paper, which is implemented by confirmingthe separating element of the coordinates step by step. Results show that the size of the coefficientsin the RUR corresponding to the separating element selected by the new algorithm is obviously shorter than that by Rouillier’s. In addition, the average complexity of both the algorithms are close.
Related Articles | Metrics
The Equivalent Representations of Invariants for 3Manifolds
HAN Youfa, ZHANG Qian, FAN Xing
J4. 2009, 47 (02):  179-184. 
Abstract ( 1264 )   PDF (424KB) ( 336 )  
Let Mbe a 3-manifold obtained by surgery on then-component framed link LS3. We can get the link invariant maintaining isotopy, and K+ and K- moves for the framed link (L, f),so as to furthermoreobtain the invariant for 3-manifold. Thus the invariants for 3-manifold are given by finite linear combinations of Kauffman brackets of cabling of L, to be evaluated at primitive 4r-th root of unity. Some difference representations of invariant for 3-manifold are given by using the bracket polynomial, TemperlyLieb algebra, JonesKauffman module and linear skein theory, etc. This paper deals with the relation of these representations of invariants, and shows essentially the consistency of them. A new representation of the invariant of 3-manifolds is also given.
Related Articles | Metrics
An Optimal PML Method for ElectromagneticScattering from Cavities
YANG Xiaoying,, MA Fuming, DU Xinwei
J4. 2009, 47 (02):  185-190. 
Abstract ( 1307 )   PDF (528KB) ( 335 )  
We developed an optimal perfectly matched layer method for scattering from cavity under both TM and TE polarizations by choosing a particular absorbing function with unbounded integral. The unbounded computational domain is truncated to a bounded one by using a rectangular perfectly matched layer at the open aperture. The thickness of PML is not very large in this method. Especially when the cavity opening is very large, the amount of calculations is saved and the operation sp eed is improved by usingrectangular perfectly matched layer instead of semicircle.Numerical experiments demonstrate that the optimal PML method is efficientand accurate to solve cavity scattering problems.
Related Articles | Metrics
Analysis of a Preypredator Model for Prey with Epidemic Disease
LI Jianjun, LI Jian, GAO Wenjie
J4. 2009, 47 (02):  191-196. 
Abstract ( 1122 )   PDF (407KB) ( 370 )  
The existence and uniqueness of the solution of a reactiondiffusion system was studied by means of the method of upper and lower solutions. Existence and nonexistence results about the nonconstant steady states of the system were given. It was also proved that if the diffusion coefficient of the prey with epidemic disease is treated as bifurcation parameter, nonconstant positive steadystate solutions may bifurcate from the constant steadystate solution under some conditions.
Related Articles | Metrics
Some Properties on Generalization QuasiP-injective Modules
ZHAO Yue, CHEN Zhengxin
J4. 2009, 47 (02):  197-200. 
Abstract ( 1355 )   PDF (271KB) ( 325 )  
We combined the known properties of quasi AP-injective modules with the way of studying quasi P-injective modules to give some new properties on quasi APinjective module. For example: Suppose MR(S=End(MR)) is quasi AP-injective, then: (1) Sis a right weakly C2 ring; (2) if for any nonempty set XM, Ls(X)is generated by an idempotent, and Sis local, left duo, then Ss is continuious.
Related Articles | Metrics
Formulae for Arithmetic on Genus 3 Hyperelliptic Curves
FU Zhiguo, SHU Hongliang, ZHANG Shugong
J4. 2009, 47 (02):  201-206. 
Abstract ( 1097 )   PDF (353KB) ( 333 )  
The explicit formula is presented for computing the reduced sum of two divisors of genus 3 hyperelliptic curves in term of Cantor’ algorithm. The experimental results indicate that our algorithm is superior to Cantor’s algorithm.
Related Articles | Metrics
Spectralconjugate Gradient Method with Inexact Line Search
MA Mingjuan,, DENG Jian, HUANG Qingdao, SUN Yao
J4. 2009, 47 (02):  207-210. 
Abstract ( 1292 )   PDF (288KB) ( 387 )  
On the basis of combining the advandage of spectralgradient method, a spectralconjugate gradient method for the global optimization is presented. This method can avoid the difficult caused by exact line search. The proof of the convergence of the proposed method is given. Numerical experiments show that the method is efficient and feasible.
Related Articles | Metrics
ShannonMcMillan Theorem of a Class of NonhomogeneousMarkov Information Source
WU Xiaotai, YANG Weiguo
J4. 2009, 47 (02):  211-215. 
Abstract ( 1037 )   PDF (264KB) ( 326 )  
The ShannonMcMillan theorem was given under the hypothesis of the countable nonhomogeneous Markov information source being supposed to be a ψ-mixing sequence. As a corollary, the ShannonMcMillan theorem of finite nonhomogeneous Markov information source was deduced.
Related Articles | Metrics
Wavelet Bases of Dilation Factor a in Generalized Besov Spaces
DAI Hongliang
J4. 2009, 47 (02):  216-220. 
Abstract ( 933 )   PDF (349KB) ( 360 )  
We obtained a wavelet representation of dilation factor a in Besov spaces of generalized smoothness via insention techniques. As a consequence, we showed that compactly supported wavelets of Daubechies type of dilation factor a provide an unconditional Schauder basis in the spaces when the integrability parameters are finite.
Related Articles | Metrics
Existence of Positive Periodic Solution of Food Chain System with Feedback Controls and Ratiodependent Functional Response
LI Hui, WANG Yifei
J4. 2009, 47 (02):  221-227. 
Abstract ( 1261 )   PDF (392KB) ( 294 )  
The existence of positive periodic solution of food chain system with feedback controls and ratiodependent response was studied by the method of coincidence, a set of sufficent conditions were derived. The continuous and ratio dependent dynamical model was improved.
Related Articles | Metrics
Radially Symmetric Solutions of Generalized Mean Curvature Equations
LU Xiushuang, WEI Bao she
J4. 2009, 47 (02):  228-232. 
Abstract ( 1319 )   PDF (281KB) ( 367 )  
The existence of the radially classical solutions with Dirichlet boundary value in unit ball was investigated. Based on perturbation technique, topological method and comparability theorem, the existence of the radially symmetric solutions for the generalized mean curvature equations with proper presupposition wasestablished.
Related Articles | Metrics
PML Method for Solving the Scattering Problems for a Class ofTwodimensional Schrodinger Equations
LI Yuan, MA Fuming
J4. 2009, 47 (02):  233-239. 
Abstract ( 1120 )   PDF (621KB) ( 266 )  
We discussed the numerical computation of the scattering problems for twodimensional Schrodinger equation (-Δ+V(x)-k2)u=0. For a class of specific potentials, i.e., V(r)=b/rδ outside a circular domain Br0, where both b>0 and δ>1 are constants, we presented a PML method. We first got the PML equationsby making the radius complex, and then proved that the sesquilinear form in the weak formulation of the PML problem satisfies the Garding inequality under the hypothesis of the absorption factor, and further could prove the existence and uniqueness of the solutions of the PML problem, finally, we gave the numerical experimentswhich show that this method is feasible to a certain extent.
Related Articles | Metrics
Mach Number Limit of a Class of Combustion Flow
YUAN Hongjun, WANG Shu
J4. 2009, 47 (02):  240-242. 
Abstract ( 941 )   PDF (187KB) ( 311 )  
The aim of this paper is to prove that compressible combustion flow in two- and three-spaces dimension converges to the incompres sible flow in the limit as the Mach number tends to zero. The proof relies on energy estimate and Helmholtz decomposition.
Related Articles | Metrics
Some Results on Periodic Cahn-Hilliard Type Equations
LI Yinghua, JIN Chunhua, HUANG Rui
J4. 2009, 47 (02):  243-244. 
Abstract ( 1061 )   PDF (193KB) ( 329 )  
This letter covers some results about periodic CahnHilliard type of equations, which include the asymptotic estimates of the solutions to the initial boundary value problems, the attractability of time periodic solutions and the asymptotic behavior of the solutions as the viscosity coefficient tends to zero.
Related Articles | Metrics
Interiorpoint QuasiNewton Method of Modified Augmented Lagrangian Function
FENG Zixuan, WANG Cailing, JI Shuguan
J4. 2009, 47 (02):  245-247. 
Abstract ( 1235 )   PDF (236KB) ( 308 )  
The quasiNewton method was applied to solving the augmented Lagrangian function of nonlinear programming problems. Further, the quasiNewton formula was given.
Related Articles | Metrics
Sum of Adjoint Regular Subrings
YU Xiaofeng, SONG Xiaolang, XIE Jingran
J4. 2009, 47 (02):  248-250. 
Abstract ( 1156 )   PDF (193KB) ( 379 )  
This note deals with the regularity of the adjoint semigroup of a ring. Acharacterization of adjoint regular rings is presented. For ring R which is a sum of two adjoint regular subrings, sufficient and necessary conditions for the regularity of the adjoint semigroup of R are given, which have extend the results given by Volkov and Tanana, and affirm their conjecture.
Related Articles | Metrics
Precise Asymptotics for the Partial Sum of Linear Processes of LPQD Sequences
TAN Xili,, YANG Xiaoyun
J4. 2009, 47 (02):  251-256. 
Abstract ( 1199 )   PDF (351KB) ( 343 )  
Let {εt;t∈Z+} be a strictly stationary sequence of LPQD random variables with mean zeros, let 021<∞,with 0<σ2<∞, {j;; j∈N } is a sequence of real numbers satisfying. Define a linear process Xt. In this article, by means of the weak convergence theorems and moment inequalities, the precise asymptotics of {Mn} and {Sn}is proved for more general weighted functions and boundary functions.
Related Articles | Metrics
2-Harmonic Spacelike Submanifolds in PseudoRiemann Manifold
HONG Taoqing, ZHANG Jianfeng
J4. 2009, 47 (02):  257-260. 
Abstract ( 1010 )   PDF (272KB) ( 356 )  
We obtained one sufficient condition under which a 2-harmonic submanifold with nonnegative sectioncurvature turns into a maximal submanifold by promoting known theorem. And We also studied the 2-harmonic hypersurfaces by weakening the conditions when the Ricci curvature of the ambient manifold had upper and lower restrict, thus improving the known results.
Related Articles | Metrics
Existence of Positive Solutions for Boundary Value Problems ofp-Laplacian Difference Equations with Time Delay
WANG Linjun, CHEN Xu mei, YIN Yunguang, GONG Chengchun
J4. 2009, 47 (02):  261-264. 
Abstract ( 1227 )   PDF (244KB) ( 287 )  
The existence of positive solutions for the boundary value problems of p-Laplacian difference equations with time delay was p roved. Sufficient conditions that guaranteed the existence of positive solutions for those problems were obtained. Furthermore, the numerical experiment was also carried out to illustrate the main result in this paper.
Related Articles | Metrics
A Note on Complete Convergence of ρ-Mixing Random Sequence
LIU Xiao ping, YAN Han, WU Qunying
J4. 2009, 47 (02):  265-268. 
Abstract ( 1225 )   PDF (277KB) ( 279 )  
We discussed complete convergence for ρ-mixing random sequence, and obtained the general equivelent relationship between the rate of complete convergence and moment condition of random variables by means of the Rosenthal type inequality of ρ- mixing random sequence and the trun cation method. The results are consistent with those for independent sequence that confirms the similarity in complete convergence between ρ-mixing sequence and independent one.
Related Articles | Metrics
A Fast Convergent Method of Iterated Regularization
LV Xiaohong, WU Chuansheng, ZHOU Jun
J4. 2009, 47 (02):  269-272. 
Abstract ( 1338 )   PDF (299KB) ( 317 )  
For linear illposed problems, the paper presents a fast convergent method of iterated regularization based on the idea of Landweber i terated regularization, and a method of aposteriori choice by the Morozov discrepancy principle, by which the optimum asymptotic convergence order of the regularized solution is obtained. Numerical test shows that the method of iterated regularization can quicken the convergence speed, reduce the calculation burden efficiently.
Related Articles | Metrics
Lattice Boltzmann Simulation of Flow Past a Rectangular Cylinder
TAN Lingyan, CHEN Mingjie, SHI Weiping, HUANG Yan jin
J4. 2009, 47 (02):  273-276. 
Abstract ( 1037 )   PDF (371KB) ( 341 )  
A twodimensional ninevelocity Lattice Boltzmann model was employed to simulate the flow past a rectangular elongated cylinder numerically. The secondorder interpolation scheme was used for the boundary treatment. The Strouhal number, the drag coefficient and lift coefficient were calculated. The streamlines and the vorticity contours were presented. Under varying the length/width ratio of the rectangular, and keeping the inlet velocity to be parallel to the length side of the rectangular cylinder, numerical results show that the Strouhal number varies linearly with the length/width ratio.
Related Articles | Metrics
Rational First Integrals of Polynomial Systems
ZHAO Hongfa, LI Wenlei, LUO Yucheng
J4. 2009, 47 (02):  277-280. 
Abstract ( 1264 )   PDF (293KB) ( 437 )  
Taking the polynomial system as a semiquasihomogeneous one, and using the so called Kowalevsky exponents, we gave a necessary condition for polynomial systems to have rational first integral. In fact, the result obtained in this paper has provided a simple criterion of nonintegrability for polynomial systems.
Related Articles | Metrics
Chover’s Law of the Iterated Logarithm forρ*Mixing Sequences
LIU Jun, TAN Xili,
J4. 2009, 47 (02):  281-285. 
Abstract ( 986 )   PDF (317KB) ( 258 )  
Let {Xn,n≥1} be ρ*mixing sequences with identical distributions belonging to the domain of the normal attraction with non-degenerate stable distribution. By means of the moment inequalities of the ρ*mixing sequences, it was proved that probability 1 possesses,and some equivaent conditions were obtained.
Related Articles | Metrics
An Improved Method for Computing Multiplying Points on Koblitz Curve Cryptography
SUN Yue gang, LI Hui lai
J4. 2009, 47 (02):  286-288. 
Abstract ( 1069 )   PDF (228KB) ( 273 )  
The authos analyzed the method existed and got an improved implementation method on Koblitz curve cryptograph on computing . The analysis shows that the efficiency was increased by a factor of over 55% and this method can be used to improve the efficiency of elliptic curve cryptography (ECC).
Related Articles | Metrics
Formal First Integrals for Periodic Systems
JIAO Jia, XU Zhiguo
J4. 2009, 47 (02):  289-291. 
Abstract ( 1104 )   PDF (204KB) ( 353 )  
Using the Floquet’s theory firstly, we gave the necessary condition of formal first integrals in a neighborhood of a constant solution for the periodic systems. Furthermore, we also gave a criterion for the partial existence of formal first integrals for these systems near some neighborhood of a constant solution.
Related Articles | Metrics
计算机科学
A Novel Approach to Clustering Co-regulated Gene
BAI Tian, ZHOU Chunguang, LIU Guixia, WANG Han, WANG Zhe, ZHANG Hongting
J4. 2009, 47 (02):  292-298. 
Abstract ( 941 )   PDF (648KB) ( 288 )  
This paper presents a new method of similarity measurement, on the basis of which an global K-means algorithm is presented that is selfadaptive to the determination of the number of cluster, so as to solve the problem that the existing methods of co-regulated gene clustering can take into account all the four co-regulating relationships, that is, reverse, asynchronous, parttime, and differences in the expression. The present algorithm has been applied to the microarray data, and the compare experimental results with CLUSTER 3.0 prove that the algorithm is efficient.
Related Articles | Metrics
Implementation of Chinese and English Clustering EngineBased on Improved Suffix Tree Algorithm
HU Hailong, SUN Chen, HE Fengling, ZUO Wanli
J4. 2009, 47 (02):  299-304. 
Abstract ( 1485 )   PDF (618KB) ( 258 )  
This paper presents an algorithm based on the improved suffix tree and interactclustering idea. Hierarchical clustering for document title and summary is implemented by improved traditional suffix tree structure. Meanwhile, the interactive clustering is employed instead of traditional recursive algorithm. The algorithm is not related with language. Not only is it applicable to wordbased English, but also it can deal effectively with characterbased Chinese without dictionarybased Chinese word segmentation. Furthermore, the interactive clustering engine was realized on the basis of the algorithm, the system was tested in different network environments, and the performance of the system was compared with other metasearch engines. The experimemnt demonstrates that it is feasible effectively to conduct realtime interactive cluste ring by using the improved suffix tree algorithm.
Related Articles | Metrics
The Economic Model Application Strategy in Computational Grids
HU Liang, HU Debin, SUN Yemeng, LIU Jia, ZHAO Kuo
J4. 2009, 47 (02):  305-310. 
Abstract ( 1258 )   PDF (662KB) ( 332 )  
The commodity market model was compared with the auction model from the aspects of resource allocation and task scheduling based on eco nomic models in computational grids. To evaluate these two models, we simulated them respectively in underdemand and excessdemand circumstances. We have examined the overall price stability, market equilibrium, producer efficiency, and consumer efficiency by simulation and drawn a conclusion that the commodity market model is more suitable to computational grids, and makes the whole resource market more fair, stable and efficient.
Related Articles | Metrics
Method for Measuring Laser Energy Density Distribution
DUAN Jin, WU Jun, DUANMU Fanyi, JING Wenbo
J4. 2009, 47 (02):  311-316. 
Abstract ( 2057 )   PDF (705KB) ( 359 )  
The methods were presented for measuring and analysising laser energy density distribution. First, the spot images were detected and lo cated. Then wavefront was fitted based on Zernike polynomial. Finally, 3D-pseudocolor visualization algorithm was used for 2D-laser spot images. Experimental results indicate that the Zernike polynomial fitting realized wavefront detection and reconstruction. The method of fitting sample points selection was studied based on the least average error of laser energy intensity testing precision. The visualizationmethod reflected the relative sizes and positions of laser spot energy distribution in different areas. The testing system fully satisfied the demand of laser energy intensity measurement.
Related Articles | Metrics
Unsupervised Kernel Fuzzy Clustering AlgorithmBased on Simulated Annealing
QU Fuheng, HU Yating, MA Siliang
J4. 2009, 47 (02):  317-322. 
Abstract ( 1323 )   PDF (533KB) ( 279 )  
As a generalization of the conventional possibilistic and kernel based possibilistic clustering model, a new kernel based possibilistic clustering model was proposed. The new approach performs the clustering by optimizing the proposed kernel possibilistic Xie-Beni index using the RJMCMC (Reversible Jump Markov Chain Monte Carlo) based simulated annealing algorithm (SA), which makes the number of clusters change in a given range and the optimal number of clusters and partitioning obtained automatically. In contrast to the conventional SA based possibilistic or kernel based possibilistic clustering, it has a higher efficiency and avoids the problem of generating coincident clusters. The contrast experiments on real and artificial data show the effectiveness of the proposed algorithm.
Related Articles | Metrics
A SVMbased System for Online Unsupervised Intrusion Detection
ZHANG Dan, REN Fei, ZHAO Kuo, ZHANG Yuan yuan,LIU Xiaobo, REN Weiwu, HU Liang
J4. 2009, 47 (02):  323-329. 
Abstract ( 1374 )   PDF (602KB) ( 470 )  
Using frequency weighting mining algorithm with realtime data processing capability to calculate each system call’s frequency value for existed audit records, we got a vector set of progresses. The vector set was linearly scanned and its progresses were labeled as “normal” or “attack” according to their distance relations. Then, we got a SVM training set without manmade supervision. Finally, the normal behavior profiles for monitoring the target system were generated by SVM classifier so as to construct a practicalon line intrusion detection system without human intervention.
Related Articles | Metrics
A Workflow Modeling to Support the Changes of Personnel and Operation Based on Ontology
LV Weijia, LIU Shufen, YAO Zhilin, XU Xiaojuan
J4. 2009, 47 (02):  330-336. 
Abstract ( 1849 )   PDF (494KB) ( 376 )  
Based on ontology theory, this paper addresses a novel workflow model that can accommodate the change of personnel and operation. To achieve the object of adapting to change more powerfully, the model adopts the method of extending the definition of conceptions and relationships inside the submodel as well as betweenthe submodels. To address the result of reducing the negative impact on the model relationships and structure, the model makes the organization, the roles and the personnel separately at different levels in the organization model. And the authority assignation model adopts the authority assignation based on task. Consequently, it also addresses the result that the change of task will not affect the organization model and will avoid the change of the complicated relationships. Especially, it makes the conception represented by ontology. Therefore, this paper produces the conclusion that the model has covered the defect of unshared feature in traditional models, at the same time, it is more secure and flexible.
Related Articles | Metrics
物理
Negative Refractive Index in a Closed Four\|level Atomic System
KANG Hai xia, KOU Jun, SU Xue mei
J4. 2009, 47 (02):  337-340. 
Abstract ( 1051 )   PDF (365KB) ( 253 )  
A closed four-level system in atomic vapor was proposed, which was made to possess left handedness by means of the technique of quantum coherence. The density matrix method was utilized in view of the rotating-wave approximation and the local-field effect in high dense gas. The conclusion of the numerical simulation shows that the medium can simultaneously exhibits left handedness in two visible frequency bands, and one can manipulate the width of the frequence bands by changing the intensity of the control field. 
Related Articles | Metrics
Structure of Nanocrystalline γ′-Fe4N Thin Films and Their Magnetic Properties at Low Temperatures
WANG Li li,, ZHAO Li jun, JIANG Wei di, ZHU Li, GONG Jie, ZHENG Wei tao
J4. 2009, 47 (02):  341-344. 
Abstract ( 1130 )   PDF (404KB) ( 264 )  
Nanocrystalline γ′-Fe4Nthin films were synthesized on single crystal Si (100) substrate by facing target magnetron sputtering. The structure and magnetic properties at room temperature and low temperatures were characterized by means of X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). The results indicate that the film had a single easy magnetized direction along (111). In a temperature range of 80~350 K, the saturation magnetization σs and coercive force Hc increased, whereas the ratio σrsdecreased with decreasing measured temperature. The relation between the coercive force Hc and temperature T obeyed the T1/2 law, the relation between σs and T did not obey the Bloch T3/2 law, which means that the interaction among spin waves should be considered. 
Related Articles | Metrics
Derivation and Applications of Mathematical Expression between Light Ray and Borderline of Two GRIN Mediums
GUO Shou yue, CAO Chun bin, SUN Zhao qi
J4. 2009, 47 (02):  345-349. 
Abstract ( 1306 )   PDF (409KB) ( 275 )  
When propagating light\|ray passes through two fixed points in the gradient index (GRIN) mediums and a cuspidal variable\|point (at this point the trace equation of propagating light\|ray is non\|differentiable) at the borderline of two different GRIN mediums, the mathematical relationship, which the trace equation of propagating light\|ray and borderline equation of two different GRIN mediums should satisfy, is derived by the Fermat’s principle and calculus of variation. Some applied examples show that the differential relationship not only contains fundamental content in geometrical optics, such as the three laws of geometrical optics, imaging formula of single spheric face, but is another form of differential equation of the light ray.
Related Articles | Metrics
电子科学
Development of Amorphous Alloy Weak Magnetic Field Sensor
YUE Xin long, HAN Bing, HUANG Dong yan, ZHANG Tao
J4. 2009, 47 (02):  350-353. 
Abstract ( 1154 )   PDF (445KB) ( 266 )  
A new single-core and double-winding magnetic field sensor prepared from Co-based amorphous ribbon was studied. Using frequency measurement approach to measuring magnetic fields increases the measurement sensitivity of the sensor. Using the closed\|loop system increases the stability of the sensor.
Related Articles | Metrics
Preparation and Test on Er3+Doped Polymer Optical Waveguide Amplifier
QI Fei, ZHANG Dan, CHEN Cong, LI Tong, SUN Xu, ZHANG Da ming
J4. 2009, 47 (02):  354-357. 
Abstract ( 939 )   PDF (465KB) ( 517 )  
The optical properties of an erbium\|doped polymer material Er(DBM)3Phen/PMMA\|GMA were researched and its absorption spectrum, refractive index and other parameters were also tested. An erbium\|doped organic polymer waveguide amplifier was fabricated by means of photolithography combined with reactive ions etching. Then the characteristics of the optical waveguide amplifier were tested by coupling the signal light and pump light into the waveguide directly. When the pump power was 150 mW and the signal power was 0.2 mW, the maximum relative gain of approximate 0.9 dB was observed on the device with a length of 1.24 cm.
Related Articles | Metrics
Detection of Weak Signals Based on Stochastic Resonance and Digital Filter
XIN Chunyu, LIU Fengxia, ZHANG Yu
J4. 2009, 47 (02):  358-361. 
Abstract ( 1044 )   PDF (418KB) ( 256 )  
Detection of weak signals in heavy noise background based on stochastic resonance was studied via numerical calculation. The relations of the amplitude and the signaltonoise ratio of the output signals of a nonlinear bistable stochastic resonance system to the noise intensity were researched under the high frequency condition. The results of numerical simulation show that the noise is restrained intensively by the nonlinear bistable system. High frequency weak signals in heavy noise background can be detected clearly based on stochastic resonance. The time domain and the characteristic spectrum of the frequency domain of output signals is obtained by extracting the high frequency weak signals with filtering wave technique. By means of the linear filter, the time domain of output signals can be obtained clearly.
Related Articles | Metrics
化学
Nondestructive Analysis of the Quality Properties of Soy Sauceby Near Infrared Spectroscopy with Partial Least Squares
BAO Chunfang, LIU Tong,, WANG Bin, ZHAO Lingzhi, REN Yulin
J4. 2009, 47 (02):  362-366. 
Abstract ( 1229 )   PDF (504KB) ( 205 )  
Nearinfrared spectroscopy combined with partial least squares (PLS) method was applied to establishingan optimal mathematic calibration model, by which the concentrations of amino nitrogen, total acid and salt content in the soy sauce were predicted, and the color ratio of the soy sauce was determined. Furthermore, the influences of spectral preprocessing methods and the numbers of principal components on the prediction ability of the PLS model were discussed. The results show that the calibration model established with firstderivative preprocessing spectra was the best, 18 samples of tested set were predicted with this model, the relative standard errors for the prediction of ami no nitrogen, total acid, salt content and color ratio were 1.516%, 1.811%, 1.798% and 1.893%, respectively. Experimental results demonstrate that this method is fast and convenient, and it has a high ability of prediction, thus it is promising for the nondestructive quality control of soy sauce.
Related Articles | Metrics
Optical Properties and Energy Transfer Mechanism of Tb3+/Gd3+Co-doped Nanometer TiO2 Thin Film
GUO Nan, GUO Kun, SHENG Ye, ZOU Haifeng
J4. 2009, 47 (02):  367-375. 
Abstract ( 1226 )   PDF (1048KB) ( 325 )  
Nanometer TiO2 thin films were prepared by means of a sol-gel process with [Ti(OBu)4] as the precursor and characterized by XRD, TG-DTA, TEM and PL spectra. XRD results show that the referentially oriented (101) anatase films were formed. TEM results show the TiO2 grainsize distribution of the sample was even and its size was about 15 nm. At room temperature, the PL intensity was found to have a well matching relation to the doping concentration of Tb3+ ions. Luminescence intensity was improved obviously after co-dopingof Gd3+ ions because of the sensitization effect of Gd3+ ions to Tb3+ ions in TiO2 system. The energy transfer mechanism from Gd3+ ions to Tb3+ ions was proposed.
Related Articles | Metrics
Dihydrogen Bonds and Traditional HBonds ofB3N3H6 with HF, HCl or H2O
LUO Hongjuan, LI Anyong
J4. 2009, 47 (02):  376-382. 
Abstract ( 918 )   PDF (659KB) ( 194 )  
The dihydrogen bonds B—H…H—X and traditional Hbonds N—H…X and X—H…X (X=F,Cl,O) between B3N3H6 and each of HF, HCl or H2O were theoretically studied by use of the ab initio quantum mechanics method (MP2). We found that the action of the dihydrogen bond made the BH and HX bonds redshifted, and that the formation of the traditional Hbonds made the NH and HX bonds redshifted. The topological properties of the complexes show that these intermolecular interactions were indeed Hbonds. The natural bond orbital analysis shows that these Hbonds can be interpreted by the theory of hypercon jugation and rehybridization.
Related Articles | Metrics
Optimization Conditions of Plant Cellulose Degradationby MicrowaveHCl/H2O2 Coupling Technique
MU Li,, ZHANG Long,, MA Liguo
J4. 2009, 47 (02):  383-386. 
Abstract ( 847 )   PDF (615KB) ( 220 )  
Under microwave heating, the degradation conditions (catalyst concentration, reaction temperature and time) were optimized, and the optimal conditions were φcatalyst= 5%, reaction temperature 100 ℃ and reaction time 2 h, with a yield of reducing sugars concentration 2.15 g/L. Under the optimized conditions, a comparative study was performed to evaluate the effects of micowave heating and conventional heating on the yield of reducing sugars, and the results show that the yield of reducing sugars obtained by the degr adation via microwave heating is increased by a factor of 33.5%, and the degradation rate is increased by a factor of 487%. The morphologies of degradation product via microwave heating and conventional heating were tested with SEM and the results show that decrease in degree of polymerisation is caused by microwave irradiation. The degradation products obtained by microwave heating and co nventional heating respectively were similar with FTIR spectra.
Related Articles | Metrics
Hydrothermal Synthesis, Crystal Structure and FluorescenceProperty of New 3D Supramolecular Compound:[Cd2(Dppz)4(1,2-BDC)2]·4H2O
LIN Hongyan, WANG Xiuli, LIU Guocheng, CHEN Baokuan, HU Hailiang
J4. 2009, 47 (02):  387-391. 
Abstract ( 1395 )   PDF (581KB) ( 222 )  
A supermolecular compound, [Cd2(Dppz)4(1,2-BDC)2]·4H2O was obtained from the hydrothermal reaction of cadium(Ⅱ) nitrate with mixed ligands [phthalic acid (1,2-H2BDC) and dipyrido[3,2-a: 2′,3′-c]phenazine(Dppz)], and structurally characterized by singlecrystal Xray diffraction. Result reveals that the compound belongs to the monoclinic system wit h space group C2/c. The cell parameters are: a=2.496 17(10) nm, b=1.7 15 96(10) nm, c=1.822 32(8) nm, β=96.293(1)°, V =7.758 6(6) nm3,  Z=4, R1=0.045 6, wR2=0.093 9. The result of fluorescence spectrum shows that the title compound exhibits blue emission in the solid state at room temperature.
Related Articles | Metrics
环境科学
Effects of Malic Acid and Succinic Acid on Sorption and Distribution of Fluoride in Tea Garden Soil
XIE Zhonglei, SUN Wentian, GUO Ping, GUO Xiaojing, GAO Fu\|min
J4. 2009, 47 (02):  392-396. 
Abstract ( 1245 )   PDF (393KB) ( 215 )  
Effects of malic acid and succinic acid on the sorption and distribution of fluoride in tea garden soil was studied by the sampling of tea garden soil and the simulated testing. The sorption capacity of fluoride by tea garden soil was depressed to some extent in the presence of malic acid and succinic acid when the initial concentration of fluoride was lower than 0.42 mmol/L for the low concentration of the organic acids and 2.1 mmol/L for the high concentration of the organic acids. The depressed function of the two organic aicds for the sorption of fluoride in tea garden soil, however, was weakened when the initial concentration of fluoride was higher than 0.42 mmol/L for the low concentration of the organic acids and 2.1 mmol/L for the high concentrationof the organic acids. On the contrary, there was a distinct enhancing function for the sorption capacity of fluoride in tea garden soil in the presence of the two organic acids with increasing the initial concentration of fluoride, and the enhancing function of malic acid was larger than that of succinic acid. The residual species was the major form and water soluble species was secondary form for sorbed fluoride under the control treatmentand in the presence of malic acid and succinic acid. There were also differences in the distributionand transformation of sorbed fluoride in tea garden soil in the presence of the different organic aicds and their concentrations, but the general distribution law of sorbed fluoride was in the order: residual>water soluble>organic≈Fe-Mn oxide>exchangeable.
Related Articles | Metrics
Reaction Condition Optimization of Butyric Acid underCatalytic Wet Air Oxidation Based onBP Artificial Neural Network Model
LI Yu,, ZHENG Shuang, WANG Jiangling, CHEN Yu
J4. 2009, 47 (02):  397-402. 
Abstract ( 1291 )   PDF (541KB) ( 223 )  
Effects of initial TOC of butyric acid, catalyst dosage, reaction temperature, and initial oxygen pressure on the degradation reaction process of butyric acid under catalytic wet air oxidation were investigated, and a BP artificial neural network model for the degradation process of butyric acid under catalytic wet air oxidation was established. The simulated efficiency factor of the model was calculated to be 0.973 2 (more than 0.80), indicating the model established could well and truly forecast the residual butyric acid in the degradation reaction process of catalyticwet air oxidation. Meanwhile, the reaction condition optimization of butyric acid under catalytic wet air oxidation based on the BP artificial neural network model was carried out, and the results show that the degradation efficiency of butyric acid under catalytic wet air oxidation was nearly enhanced by 20%.
Related Articles | Metrics