Journal of University of Chinese Academy of Sciences

Proportional Bootstrap and the consistency of corresponding variance esitmators

Yang Jun, Zou Guo-Hua

2007, 24 (3): 273-279. DOI: 10.7523/j.issn.2095-6134.2007.3.001

This paper studies the proportional Bootstrap method on missing data, and
compares it with the usual Bootstrap method. Under the simple random sampling and
uniform response, using regression imputation and ratio imputation for missing data,
the consistency of the variance estimators obtained by proportional Bootstrap is proved.
Simulation results give a verification on our theoretical conclusions.

On 3D graphical representation of DNA sequences

Chi Ru, Gao Sui-Xiang

2007, 24 (3): 280-286. DOI: 10.7523/j.issn.2095-6134.2007.3.002

Abstract ( 1315 ) PDF (KB) ( 6 )

We outline a novel 3D graphical representation of DNA sequences, which can avoid crossing and overlapping of the corresponding spatial curve. And the advantage is that we can just consider two different conditions, but three conditions in other 3D representations. As application, we construct a 2-component vector whose components are the normalized leading eigenvalues of the L/L matrices associated with DNA sequence based on the two conditions, to examine the similarities/dissimilarities among the coding sequences of different species.

Study on the life annuity actuarial present value models of annuity portfolio insurance

Li Chang-Lin

2007, 24 (3): 287-290. DOI: 10.7523/j.issn.2095-6134.2007.3.003

Abstract ( 1162 ) PDF (KB) ( 0 )

Many researchers studied the life Annuity because it is very important. Firstly, A generalized stochastic interest rate model is derived by using time series. We then get the life annuity actuarial present value models of annuity portfolio insurance through the portfolio theory, under independent stochastic interest rates environment.

Inhibitory effects of Sichuan brick tea extracts on fatty acid synthase

JIANG Bo, TIAN Wei-Xi, QI Gui-Nian

2007, 24 (3): 291-299. DOI: 10.7523/j.issn.2095-6134.2007.3.004

Abstract ( 1644 ) PDF (KB) ( 0 )

Sichuan brick tea (Kang Zhuan) contains different tea polyphenols from green tea and black tea. The inhibition on Fatty acid synthase (E.C.2.1.3.85, FAS) by the extracts of brick tea is measured by inhibition kinetics. FAS has been reported as a potential new therapeutic target for both cancer and obesity. The results show that the inhibition included both reversible and irreversible process. The optimal solvent for extracting FAS inhibitors is 50% ethanol. The extraction achieved during 5 hours in room temperature. The boiling water could extract about total 60% effective FAS inhibitors by two times extraction. The final efficiency is two-folds of that for green tea, but longer time is needed for the extraction. The inhibition of FAS by new brick tea was not stronger, and brick tea stored for several years showed most inhibitory activity. More storage time lead to decrease some inhibitory ability of brick tea but not very much for over 20 years. It is seems that the storage over 30 years markedly weakens the ability of brick tea. The brick tea extracts inhibited the overall reaction of FAS in a mixed manner of competitive and noncompetetive with acetyl-CoA and malonyl-CoA. It inhibited the ketoacyl reduction of FAS weakly, which indicated that the ketoacyl reductase domain is not the main reacted site that brick tea extracts attracted. These results shows that inhibitor in brick tea is different from that in green tea and black tea. It is proposed that the effective in brick tea should be theabrownine(TB), which inhibitory ability is higher than catechins and is closed with theaflavins. The results exhibited applicable foreground of brick tea for fat-reducing and anti-cancer.

A generation tool of test case based on security model

HUANG Liang, FENG Deng-Guo, ZHANG Min

2007, 24 (3): 300-306. DOI: 10.7523/j.issn.2095-6134.2007.3.005

Abstract ( 1426 ) PDF (KB) ( 0 )

During the security evaluation of security products, one of the difficulties is the lack of proper test cases. Current automatic test case generation tools cannot completely solve the problem. Because, most specifications of information security products such as the Secure Database Management System (SDBMS) cannot reflect the systems’ real behavior. Besides the requirements of the product specification, the system must also satisfy the requirements of the security policies. In this paper, we present the design and implementation of CaseBuilder, an automatic test case generating tool, which has adopted a test case generating method based on product’s security policies. As the result of prototyping, CaseBuilder can generate test cases for SDBMS effectively, which can satisfy the testing requirement of security policy model well.

Surface reconstruction based on Catmull-Clark subdivision

Liu Hao, Liao wen-He

2007, 24 (3): 307-315. DOI: 10.7523/j.issn.2095-6134.2007.3.006

Abstract ( 1837 ) PDF (KB) ( 0 )

Based on the shrink-wrapping algorithm, this paper presents an approach to reconstruct Catmull-Clark subdivision surfaces from unstructured triangular meshes. Attracting / relaxing operators are designed using properties of Catmull-Clark subdivision. By presenting the reserving convexity constraint and the flat degree constraint, the base mesh can reserve sharp characters in the simplified triangular mesh and mesh edges do not cross after the base mesh is subdivided. By using these methods, such as the push-back subdivision scheme, the attracting operator and the relaxing operator in quadrangular meshes, the approach need not distinguish sharp characteristic while reconstructing surfaces. It can deal with the whole mesh by the single algorithm. Main components of the approach are constructing base meshes, adjusting vertices of subdivision meshes, choosing subdivision schemes and analyzing errors of subdivision surfaces.

Comments on an efficient group signature scheme

ZHOU Su-Jing, LIN Dong-Dai

2007, 24 (3): 316-319. DOI: 10.7523/j.issn.2095-6134.2007.3.007

Abstract ( 1459 ) PDF (KB) ( 0 )

Group signature schemes are extended from ordinary digital
signatures motivated by many applications. Zhang et al. proposed an e±-
cient group signature scheme which was claimed more e±cient than the well
known ACJT scheme, due to the reason that expensive signature of knowl-
edge, a component in a majority of group signature schemes, was avoid in
generating the group signature. In this paper, we point out that Zhang et
al.’s scheme actually adopts signature of knowledge, and it is insecure com-
pletely because of inappropriate design.

Design of high resolution camera system based on full frame CCDs

LIU Guang-Lin, YANG Shi-Hong, WU Qin-Zhang, XIA Mo

2007, 24 (3): 320-324. DOI: 10.7523/j.issn.2095-6134.2007.3.008

Abstract ( 2463 ) PDF (KB) ( 0 )

A design of high resolution camera system based on DALSA’ s CCD evaluation kit EKxxxx was presented. It was composed of a pulse pattern generator (SAA8103), a vertical line driver (TDA9991), four analog-to-digital interfaces (TDA9965) and a system controller (P89LV51RD2). Camera link with medium configuration was adopted to transfer digital images. The software for controlling and debugging the camera was developed. To correct the non-uniformity of 4 outputs, a method based on two-point correction was described. The system can acquire ultra high resolution pictures at a high frame rate thus it is suitable for aero photography.

Fourth-order cumulant based CSPRIT algorithm

SHEN Yi-Ping, HOU Chao-Huan, MA Xiao-Chuan

2007, 24 (3): 325-330. DOI: 10.7523/j.issn.2095-6134.2007.3.009

Abstract ( 1326 ) PDF (KB) ( 0 )

By analyzing the problems of CSPRIT algorithm based on second-order statistics under space correlated Gaussian noise, a new algorithm combining fourth-order cumulant and CSPRIT algorithm is proposed to process one-dimensional signal sources, such as binary phase shift keying (BPSK) and M-ary amplitude shift keying (MASK). DOA estimation and beamforming construction can be achieved simultaneously in this way. Compared to the original CSPRIT algorithm, this improved algorithm based on fourth-order cumulant can depress space correlated Gaussian noise well and get more accurate estimation of signals. The validity of this algorithm is also proved by computer simulation.

Hybrid parallel PN code acquisition technique for LEO satellite communication

SHUAI Tao, LIU Hui-Jie, LIANG Xue-Wen

2007, 24 (3): 331-335. DOI: 10.7523/j.issn.2095-6134.2007.3.010

Abstract ( 1724 ) PDF (KB) ( 0 )

A hybrid Parallel PN code acquisition scheme is investigated for burst mode spread spectrum communication with high doppler frequency offset. Based on LEO satellite channel, analysis of post detection integration and detection threshold to average acquisition time are given. Aimed at minimum acquisition time, an optimal threshold and post detection integration are put forward in this paper.

Image error concealment base on lossless self-embedding

QIAN Zhen-Xing CHENG Yi-Min GE Shi-Min ZENG Dan

2007, 24 (3): 336-341. DOI: 10.7523/j.issn.2095-6134.2007.3.011

Abstract ( 1312 ) PDF (KB) ( 0 )

This paper presents an image error concealment method using lossless self-embedding. JPEG image is downsampled and halftoned to binary image, which is embedded into the low & middle DCT coefficients using lossless data hiding method. When extracting data, original image can be recovered losslessly, and a low-quality image is reconstructed from the hidden data using inverse halftoning and upsampling. Errors on the image can be concealed with the low-quality image.

Modeling and analyzing of TCP fairness in wireless mesh network

ZHANG Lei, YANG Shou-Bao, WANG Da-Peng, SUN Wei-Feng

2007, 24 (3): 342-350. DOI: 10.7523/j.issn.2095-6134.2007.3.012

Abstract ( 1560 ) PDF (KB) ( 0 )

TCP unfairness is a critical problem in Wireless Mesh Network. Fair TCP services with high quality are difficult to obtain. While modeling for the related protocols of different layers will greatly help us analyze the active factors of TCP fair transmission and come up with better protocol design for Wireless Mesh Network. The state transitions of MAC and TCP were modeling based on Markov chain in typical IEEE 802.11b/g based Wireless Mesh Network. Then, the TCP delay and throughput were analyzed based on the modeling. The contrast between simulation results and theoretic values of delay and throughput proves that the modeling and analyzing are correct. The important influence factors found are helpful for research on TCP fairness in Wireless Mesh Network.

Vortex-induced vibration of submerged floating　tunnel tethers in shear current

GE Fei, HUI Lei,　HONG You-Shi

2007, 24 (3): 351-356. DOI: 10.7523/j.issn.2095-6134.2007.3.013

Abstract ( 1176 ) PDF (KB) ( 0 )

The engineering analysis method for vortex-induced transverse vibration of submerged floating tunnel (SFT) tether is presented, based on the modified wake oscillator model. The effects of specific gravity ratio and shear current character on vortex-induced vibration of tether are investigated. The calculated results show that the distribution of lock-in regions and the vortex-induced vibration of tether vary with the specific gravity ratio of SFT. The increase of shear parameter makes the amplitude of vortex-induced vibration decrease. Furthermore, if shear current is replaced by uniform current to calculate the vortex-induced vibration of tether, its response amplitude may be overestimated.

Combination extracting main functional protein such as thrombin and immunoglobulin from pig plasma

LI Min-Kang, QIAN Dong-Ming, SONG Hong-Xin

2007, 24 (3): 357-361. DOI: 10.7523/j.issn.2095-6134.2007.3.014

Abstract ( 1441 ) PDF (KB) ( 0 )

A effective method of extracting functionality protein such as albumin、immunoglobulin、fibrinogen and thrombin from pig plasma was introduced in this article. Extracting fibrinogen with freeze-thawing method and thrombin from supernatant by absorbing test, then salt out to distill albumin and immunoglobulin. In 1L pig plasma ，about 31.41g albumin and 13.86g immunoglobulin and 0.22g thrombin and 2.67g fibrinogen have been extracted. The specific activity of thrombin is 38.5U/mg.

Cloning, expression and preparation of polyclonal antibody for human Dcp2 gene

LIU Li-Xin, LIU Shu-Feng, Chang Nai-Bai, Liu Hui, Wang Wei

2007, 24 (3): 362-367. DOI: 10.7523/j.issn.2095-6134.2007.3.015

Abstract ( 1276 ) PDF (KB) ( 0 )

The degradation of eukaryotic mRNAs plays important roles in the modulation of gene expression, quality control of mRNA biogenesis. Dcp1/Dcp2 is a major component of mRNA decay factors. However, the more detail mechanisms of Dcp1/Dcp2 in mRNA degradation are unknown. In this study, our object is to amplify Dcp2 gene from human brain cDNA library, then to prepare rabbit-anti-human Dcp2 polyclonal antibodies. Our results showed that anti-Dcp2 rabbit polyclonal antibody was obtained. The antibody could detect the endogenous Dcp2 expression and its cell localization by both Western Blotting and immunohistochemistry, and Dcp2 protein also could be enriched by immunoprecipitation with this antibody. Therefore, this work provides a useful tool for further functional study of Dcp2 gene.

The clinical significance of the serum levels of vascular endothelial growth factor and interleukin-12 in acute leukemia patients

Gao Li-jun, Xia wei, Du Bing-Yang

2007, 24 (3): 368-371. DOI: 10.7523/j.issn.2095-6134.2007.3.016

Abstract ( 1258 ) PDF (KB) ( 0 )

Objective We measured serum vascular endothelial growth factor and interleukin12 levels in acute leukemia samples and correlates these levels with disease characteristics and prognoses. The purpose of this research was to reveal the clinical relevance between VEGF and interleukin 12 of acute leukemia. Methods The serum VEGF and interleukin 12 levels were measured by quantitative Enzyme linked immunoassay (ELISA) which were applied to the groups of 10 untreated period, 10 complete remission period, 5 relapse period patients and 9 normal control. Results The concentrations of VEGF of untreated group(521.06± 163.85 pg/ml) were higher than complete remission(307.62±55.40 pg/ml) and normal group(262.01±141.66pg/ml). Differences existed between the concentrations of IL-12 in untreated group or relapse, complete remission and normal group. Negative correlation was found between the concentrations of VEGF and IL-12 in the normal group. The concentrations of VEGF and IL-12 were certain associated with the clinical condition of acute leukemia.

Algorithm for Detecting Firewall Policy Inconsistency

WANG Wei-Ping, CHEN Wen-Hui, LI Zhe-Peng, CHEN Hua-Ping

2007, 24 (3): 372-379. DOI: 10.7523/j.issn.2095-6134.2007.3.017

Abstract ( 1279 ) PDF (KB) ( 0 )

As a traditional technique of information security, firewall has taken very important position. Security administrators frequently have to compare firewall policies looking for inconsistence, while it is not a smooth process to choose a platform for the comparison. To realize the comparison between firewalls’ policies, this paper provides FPT(firewall policy tree) model, and the construction algorithm which can turn a firewall policy into a policy tree, as well as the comparison algorithm, finally presents the procedures of comparing firewalls’ policies. Combination of the two algorithms can be used to perform a comparison between firewalls’ policies. By doing this, the paper can obtain the set of data packages on which different firewalls have made inconsistent filter decision, and finds out the inconsistency in firewalls’ policies.

A modified dual-band microstrip patch antenna with U-slot

LI Xin, DING Jun, LV Xiao-De

2007, 24 (3): 380-383. DOI: 10.7523/j.issn.2095-6134.2007.3.018

Abstract ( 1465 ) PDF (KB) ( 0 )

A novel microstrip antenna with a U-slot on the patch is presented in this paper, which satisfy the requirements of wireless local area network(WLAN) 2.4GHZ(802.11b) and 5.2GHz(802.11a) applications. The lower and higher resonant frequencies can be easily tuned by adjusting a few antenna parameters. We design this antenna by using computer simulation program Ansoft HFSS, and some optimizing
Followed . The model achieves the required WLAN specifications in terms of beamwidths, gain and cross-polarization level. The antenna bandwidth is 100MHz at 2.4GHz and 300MHz at 5.2GHz, respectly.

Robust adaptive control design for a class of nonlinear uncertain neutral multiple time-delay systems

WANG Yan-Qing JIANG Chang-Sheng

2007, 24 (3): 384-390. DOI: 10.7523/j.issn.2095-6134.2007.3.019

Abstract ( 1053 ) PDF (KB) ( 0 )

The robust stabilization for a class of nonlinear uncertain neutral systems with multiple time delay is mainly discussed. Because the uncertainty of this class of system is bounded by a linear function of the norm of the delayed states with unknown bounds, an adaptive update law is proposed to estimate the square of these unknown bounds. An adaptive control law is thereafter constructed. It is proved by Lyapunov stability theory that the solution of the closed loop system which includes the original system, the adaptive control law and the update law is uniformly ultimately bounded. Finally, a numerical example is given to demonstrate the effectiveness of the method.

Quantum Information Processing (QIP) and Realization Using Nuclear Magnetic Resonance

WEI Da-xiu, ZENG Xi-Zi, LIU Mai-Li

2007, 24 (3): 391-399. DOI: 10.7523/j.issn.2095-6134.2007.3.020

Abstract ( 1388 ) PDF (KB) ( 0 )

This paper presents our theoretical and nuclear magnetic resonance(NMR) experimental work on several QIPs including quantum super dense coding (QSDC), quantum algorithms, quantum error correction, and decoherence-free subspace. The main contents are, 1) Using NMR technique, we realize two kinds of QSDC. The experimental results show that QSDC only needs to transfer (N-1) qubits during transmitting N bits classical information; 2) On NMR quantum computers, we realize three kinds of quantum algorithms that including four-qubit summing algorithm, four-qubit Deutsch-like algorithm and seven-qubit Deutsch-Jozsa algorithm. 3) We present a quantum error correction scheme based on quantum cloning. This scheme shows the relationship between quantum cloning and quantum error correction. 4) To avoid decoherence in quantum algorithms, we construct a decoherence-free subspace (DFS) by using multiple quantum coherences. The validity of this DFS is also experimentally verified on our NMR quantum computers. The DFS makes the three unaddressed protons in a CH3 group distinguished in two-dimensional (2D) NMR. It can protect against more error operators. This idea may provide new insights into extending the number of qubits in the sense that it effectively utilizes the magnetically equivalent nuclei.

Current Issue