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2008, Vol.25, No.5 Previous Issue    Next Issue
Research Articles
The research progress of large-scale data parallel visualization in geosciences
Chen Shaolin, Zhang Huai, Shi Yaolin
2008, 25 (5): 577-584.  DOI: 10.7523/j.issn.2095-6134.2008.5.001
Abstract ( 1766 ) PDF (KB) ( 4 )

Visualizing and analyzing the explosive datasets coming from observation and simulation in the geosciences is becoming great challenge. Using parallel visualization technique to visualize the large-scale geosciences data is an effective solution. We discuss the usage of large-scale data parallel visualization in the geosciences in the paper. We firstly introduce the several parts of large-scale data parallel visualization, then characterize the features of large-scale data of geosciences, at last, we discuss the usage of parallel visualization of large-scale data in the visualizing simulation results of mantle convection, seismic wave propagation and tsunami.

论文
Smoothness of the curvature of an HCMU on S2 or T2
Wu Ying-yi
2008, 25 (5): 585-591.  DOI: 10.7523/j.issn.2095-6134.2008.5.002
Abstract ( 1020 ) PDF (KB) ( 0 )

An HCMU is a kind of extremal metric with singularities on a Riemann surface. If the area and Calabi energy are both bounded, the Gauss curvature of an HCMU is a continuous function on the Riemann surface. In this paper we get an explicit construction of an HCMU on S2 which has no saddle point of the Gauss curvature of the metric. Further more we prove that on S2 or T2 the Gauss curvature of an HCMU is smooth if and only all of the singular angles are integers.

Blowing-ups of valuation rings
Xu Ning
2008, 25 (5): 592-597.  DOI: 10.7523/j.issn.2095-6134.2008.5.003
Abstract ( 984 ) PDF (KB) ( 0 )
From the infinite sequences of blowing-ups we get two valuation rings in cases of both discrete and nondiscrete in exercise 4.12 of Hartshorne's Algebraic Geometry.
Molecular dynamics study on thermal conductivity of diamond nanoparticles
Li Xiao-Bo, Tang Da-Wei, Zhu Jie
2008, 25 (5): 598-601.  DOI: 10.7523/j.issn.2095-6134.2008.5.004
Abstract ( 1882 ) PDF (0KB) ( 0 )
By using molecular dynamics (MD) simulation method, we studied temperature dependence and nanoparticle-size dependence of thermal conductivity of diamond nanoparticles. In order to get more reliable results, equilibrium molecular dynamics (EMD) method was applied. We set a relatively long integral time in the calculation of heat current autocorrelation function (HCACF), and got convergent results. Our results indicate that due to size effect, thermal conductivity of diamond nanoparticles is smaller than the one of bulk diamond. As temperature varies, thermal conductivity shows a peak value at 61.6K, which behaves a little different from bulk diamond. As particle size increases, thermal conductivity increases; from the tendency of our plot, we predict that thermal conductivity of diamond nanoparticles will converge at the value of bulk diamond with a proper size. More work will be done on this prediction in our future researches.
A Pattern and Simulation Framework of Emergent Algorithms for Survivability
Huang Yan-Fang, Zhang Yu-Qing, Chen Shen-Long
2008, 25 (5): 602-610.  DOI: 10.7523/j.issn.2095-6134.2008.5.005
Abstract ( 1208 ) PDF (0KB) ( 0 )
Survivability is one of research focuses of network security. This paper classified the target systems of survivability into Bounded Systems and Unbounded Systems and deemed Emergent Algorithms as a suitable solution to enhance the survivability of Unbounded Systems. A pattern of Emergent Algorithms is proposed using Multi-agent System and protocol to model the system. By deploying survivability control agents and designing the protocol among agents the survivability of the target Unbounded Systems is enhanced. Simulation framework to verify and evaluate Emergent Algorithms is also proposed.
论文
Security analysis of a key agreement protocol for mobile Ad Hoc network
Xu Jing
2008, 25 (5): 611-614.  DOI: 10.7523/j.issn.2095-6134.2008.5.006
Abstract ( 1249 ) PDF (KB) ( 0 )

As a new type of wireless mobile networks, Ad Hoc networks do not depend on any fixed infrastructure, and have no centralized control unit and so its computation capabilities are limited by mobile nodes. Recently, Wang, et al. proposed a novel multi-party key agreement protocol with password authentication and sharing password evolvement for Ad Hoc networds and claimed their protocol secure and efficient. However, the research shows the protocol is insecure against off-line password guessing attack and forgery attack. We also point out that the protocol does not meet forward security, backward security and dynamic key evolvement.

UCKG-based key management protocol
Yang Fu-Rong , Liu Chang-Jin
2008, 25 (5): 615-619.  DOI: 10.7523/j.issn.2095-6134.2008.5.007
Abstract ( 1345 ) PDF (KB) ( 0 )
Key management protocol is a key problem for Ad hoc network security. In this paper, we introduced a user contributed key generation strategy (UCKG) based on the identity based cryptography (IBC). Compared to IBC key generation strategy, UCKG has no PGC-cheating problem and no requirement of secure channel for key distribution. We also proposed a distributed key management protocol for UCKG and simulated it with NS-2. The simulation results show that while the network had the good connectivity, the distributed key management protocol has good performance.
Over-sampling subband pulse compression analysis and its
application in SAR
Song Xiu-feng, Wang Fei, Yu Wei-Dong
2008, 25 (5): 620-625.  DOI: 10.7523/j.issn.2095-6134.2008.5.008
Abstract ( 1056 ) PDF (0KB) ( 0 )
Wide-band radar has high range-resolution, and we can get more detailed information from its reflection echoes. But excessive computation and data storage limit its real-time processing. Rabinkin suggested an over-sampling subband pulse compression(OSSPC) approach to overcome the disadvantage. In this paper, OSSPC’s structure and optimization method were introduced at first, and then we analyzed the computation complexity of each subband and offered a formula to calculate the Amdahl accelerated rate. Secondly, a subband Range-Doppler algorithm was introduced at last, and its validity was confirmed by computer simulation.
LOIS grub: A configurable trusted booting system
XU Zhen , SHEN Li-Hong , Wang Dan
2008, 25 (5): 626-630.  DOI: 10.7523/j.issn.2095-6134.2008.5.009
Abstract ( 1311 ) PDF (0KB) ( 0 )
Security of the booting process in a computing system is a starting point of the security of the overall system. Secure booting system will guarantee that entities in the booting chain have not been tampered. On the other hand, trusted booting system based on TPM can only record evident chain during system booting without further processing. This paper presents a configurable trusted booting system which can be configured to boot the system in secure mode or trusted mode and can further support fine-grained file verification and kernel recovery. Prototype shows that the system can reach its design goals.
论文
How to choose proper parameter values for poker test
Chen Hua, Fan Li-Min
2008, 25 (5): 631-638.  DOI: 10.7523/j.issn.2095-6134.2008.5.010
Abstract ( 955 ) PDF (KB) ( 2 )
Poker test is one of the basic statistical tests for judging whether or not a binary sequence is random. It belongs to the kinds of statistical tests that need extra parameter values as input. In this paper, how to determine the proper parameter values for poker test is explored and through a large number of experiments, we find some parameter values seem to be able to act as the representative ones.
A network vulnerability evaluation method based on Bayesian networks
CHEN Si-Si, LIAN Yi-Feng , Jia Wei
2008, 25 (5): 639-648.  DOI: 10.7523/j.issn.2095-6134.2008.5.011
Abstract ( 1453 ) PDF (0KB) ( 0 )
Network vulnerability evaluation is a hot topic of network security research. In this paper we analyze and compare the existing network security model and quantitative assessment methods. Considering all the security-related factors of network in vulnerability evaluation, we propose a set of evaluation metrics that includes reliability parameters of network, criticality parameters of network, lowest degree minimal path set and lowest degree minimal cut set .We also propose a new method of quantitative assessment based on Bayesian network. Finally we give an example to simulate the net-attack using SPIN and validate vulnerability evaluation indices and methods. The result shows that the method and the evaluation indices could evaluate and reflect the security state of network successfully.
An approach for compliance validation of TPM through applications
CUI Qi, SHI Wen-Chang
2008, 25 (5): 657-664.  DOI: 10.7523/j.issn.2095-6134.2008.5.012
Abstract ( 1399 ) PDF (0KB) ( 3 )

Security involves both protection and compliance. Although the Trusted Computing Group (TCG) has defined specifications for Trusted Computing, including those of Trusted Platform Module (TPM), criteria on compliance testing is still not available. In this paper, a test mechanism checking TPM commands is instrumented into TPM applications, which will validate TPM’s conformance to specifications before its functional execution. Based on this, the initial idea of a chain of compliance is also discussed to enhance the trustworthiness of computing platforms by verifying the conformance of their components.

Distribution of amino sugars in forest soil profiles of the Changbai Mountain
XIE Hong-Tu, LI Wei-Fu, BAI Zhen, HE Hong-Bo, ZHANG Xu-Dong
2008, 25 (5): 657-664.  DOI: 10.7523/j.issn.2095-6134.2008.5.013
Abstract ( 1315 ) PDF (0KB) ( 0 )
The vertical distribution of three amino sugars and the contribution to organic matter pools in the soil profiles of the Changbai Mountain were discussed. The composite samples of organic layers and mineral horizons were collected at three sites (altitude, 600m, 1680m and 2580m) on the northern slope of the mountain. The contribution of three amino sugars to the total amounts of amino sugars was in the order glucosamine (GlucN) > galactosamine (GalN) > muramic acid (MurAc). The contents of amino sugars and the proportion of amino sugars to soil organic matter in the profiles increased from the top organic layer until A horizons, but they varied among the subsoil horizons. The ratios of GlucN/MurAc and GlucN/GalN in the soil horizons at different altitudes indicated that they might originate from different microbial communities.
Robust recursive algorithm for real-time co-correction model
ZHAO Chao, HONG Hua-sheng, ZHANG Luo-ping
2008, 25 (5): 665-670.  DOI: 10.7523/j.issn.2095-6134.2008.5.014
Abstract ( 1273 ) PDF (0KB) ( 0 )
Data observed by telemetric system often carries outliers resulting from instrument malfunctioning, false signal acquisition because of signal leak, collision and disturbance during signal transmission, and special measuring demand of hydrologic variable, in addition to unavoidable random errors. When the parameters of real-time co-correction model are estimated by the abnormal data, the algorithm must not only be able to resist the effect of the outliers, but also have ability for real-time tracing of the changes of parameters. In this paper, a robust recursive least-squares algorithm with a forgetting factor is produced based on the recursive least-squares algorithm. And a example is given to demonstrate that the algorithm is insensitive to the outliers and is adapt to the time-varying parameter estimation.
The effect of lactose substituted by rice syrup on the blood bio-chemical index and hormone level for weaning pigs
KANG Ping , HUANG Rui-lin, YIN Yu-long
2008, 25 (5): 671-676.  DOI: 10.7523/j.issn.2095-6134.2008.5.015
Abstract ( 1149 ) PDF (0KB) ( 0 )
The effects of rice syrup as a substitute for lactose on blood bio-chemical index and hormone level in weanling pigs were studied. A total of 32 weanling barrows (Yorkshire ×Landrace) initially weighing 2.68±0.34 kg and 7d of age were placed in individual cages. Sixteen pigs were randomly assigned to one of two dietary treatments: (1) control, 43% lactose and (2) treatment 1, 0% lactose. Five pigs from each treatment were randomly selected for termination on 14d and 21d, respectively. When the lactose was replaced by the rice syrup, the serum cholesterol was significantly decreased on 14d(p<0.05), but there was no effect on 21d(p>0.44). As for the total protein, total triglyceride and insuline, there was no difference between the control and the treatment(p>0.05). The serum gastrin concentration had no difference between the two groups on 14d(p>0.05), but it was higher in the control than the treatment on 21d(p<0.05). The serum T3 level was higher in the control than the treatment on 14d(p<0.05), but there was no difference between the two groups on 21d(p>0.05). The serum T4 level was significantly higher in the control than the treatment on 21d(p<0.01), but there was no difference between the two groups on 14d(p>0.05).The result suggested that the lactose could stimulate the cholesterol absorption, but had no effect on the protein and fat metabolism, moreover, the stomach might not be the main place for digesting the lactose, the low lactose level and rice syrup could decrease the PH in the pigs’ stomach.
Study on the stock markets of China: based on Shanghai composite index and dividend index
Li Chang-lin, Chen-Min
2008, 25 (5): 677-681.  DOI: 10.7523/j.issn.2095-6134.2008.5.016
Abstract ( 936 ) PDF (0KB) ( 0 )
Based on the Shanghai dividend index and Shanghai composite index, the paper explores the bubbles of Shanghai stock market empirically by using the method of unit root and cointegration. The empirical result shows that our stock markets have bubbles (including irrational bubbles) obviously from 2005.
Analysis of Shanghai and Shenzhen stock market using Copula-VaR method
Hao Li-Xiang, Cheng Xi-Jun
2008, 25 (5): 682-686.  DOI: 10.7523/j.issn.2095-6134.2008.5.017
Abstract ( 1506 ) PDF (0KB) ( 14 )
Risk analysis of Portfolio is studied ,by comparing Copula functions and the traditional VaR methods,mixing copula is made. By backtesting ,the empirical research shows that mixing Copula method makes better VaR model .
论文
Purity and coherence compensation by using interactions between particles in quantum system
Lou Yuesheng, Cong Shuang
2008, 25 (5): 687-697.  DOI: 10.7523/j.issn.2095-6134.2008.5.018
Abstract ( 1151 ) PDF (KB) ( 0 )
In this paper, problems of compensation for purity of particle in a mixed state and counteraction against decoherence process are investigated. A new method utilizing an assistant particle and its interactions with the target particle to compensate purity and coherence is proposed. Compensations for two different situations are considered: purity compensation for the target particle in a mixed state and counteraction against decoherence process. Conditions of the assistant particle for each situation are obtained. System numerical simulations are done to validate the validity of the method proposed.
Cryptanalysis of a signature scheme without using one-way Hash functions
GUO Li-Feng, LI Yong, HU Lei
2008, 25 (5): 698-700.  DOI: 10.7523/j.issn.2095-6134.2008.5.019
Abstract ( 1671 ) PDF (0KB) ( 0 )
In 2004, Chang, et al. proposed a digital signature scheme without
using one-way hash function and message redundancy schemes. But Zhang
showed that the scheme can be forged. In order to overcome Zhang’s attack, Zhang et al. demonstrated an improved signature scheme based on Chang et al.’s signature scheme and analyzed the security of the improved scheme. But
in this paper, we identify a simple attack to show Zhang, et al.’s scheme is still
not secure. To resist this attack, the hash function and message redundancy
schemes may be still used.
简报
A linear algorithm based on complete linear transformation for analytic solution of difference equation
Song Ji-Feng, Ge Yun-Jian
2008, 25 (5): 701-706.  DOI: 10.7523/j.issn.2095-6134.2008.5.020
Abstract ( 1107 ) PDF (KB) ( 0 )
It is difficult to get the analytic solution of difference equation by using traditional methods with computer. A linear method based on complete linear transformation for getting the analytic solution of difference equation is proposed in this paper. The idea of this new method is dimensionality reduction. The orders of the high-order difference equation are reduced through determinant calculation, and this process is repeated till the last analytic expression of the solution of the difference equation appears. In essence, this algorithm is a transformation of Z-transform method combined with linear algebra method. The linear property of this algorithm enables one to get analytic solution other than numerical solution of difference equations using computer.
The Shine-Dalgarno local structure determines translation
efficiency of mRNA in Escherichia coli
Zhou Qing-Ming, Zhang Hong
2008, 25 (5): 707-711.  DOI: 10.7523/j.issn.2095-6134.2008.5.021
Abstract ( 1026 ) PDF (KB) ( 0 )
We established a simple mathematical model that the degree of polyamine stimulation of mRNA translation was dependent on the structure of the Shine-Dalgarno (SD) sequence in Escherichia coli. Loose base pairing of the SD sequence with other regions of mRNA caused strong polyamine stimulation, while intense base pairing of the SD sequence with other regions of the mRNA resulted in insignificant weak polyamine stimulation. The result suggested that the protein expression level was relative to the exposure probability of the SD sequence from its base paired state by the polyamine stimulation. The model agreed well with the experimental analysis.
Populating galaxies in dark matter halos
Yang Xiao-Hu, Chu Yao-Quan
2008, 25 (5): 712-720.  DOI: 10.7523/j.issn.2095-6134.2008.5.022
Abstract ( 1028 ) PDF (0KB) ( 0 )
In this paper we summarize part of our work presented in the thesis of Yang, et al. entitled "The Statistical Research of Large Scale Structure in the Universe". There are four chapters in the thesis: chapter 1, the background of the large scale structure and galaxy formation; chapter 2, constructing a LAMOST mock catalogue; chapter 3, the applications of the discrete wavelet transformation in the large scale structure studies; and chapter 4, linking the galaxies with dark matter halos. Here we focus on the work presented in chapter 4, where we used the weak lensing measurements to constrain the galaxy luminosity-dark matter halo relations and established a conditional luminosity function model (L|M)dL, which gives the number of galaxies with luminosities in the range L ± dL/2 that reside in a halo of mass M. The conditional luminosity function derived from the present data plays an important role in the establishing of the galaxy formation models and can help us to predict several statistics about the distribution of galaxy light in the local Universe. We show that roughly 50 percent of all light is produced in haloes less massive than 2 × 1012 h&#8722;1M⊙.