Journal of University of Chinese Academy of Sciences

A Review on Methods of Organic Silicone-Acrylate Copolymerisation

CAO Shun-Sheng, LIU Bai-Ling, DENG Xiao-Bo, LUO Rong, CHEN Hua-Lin

2006, 23 (4): 433-441. DOI: 10.7523/j.issn.2095-6134.2006.4.001

Organic siloxane and its polymer, due to the obvious advantages on the water repellency, weather resistance, low glass transition temperature and low surface energy etc, have a diversity of applications in polymer materials field. Its application, however, is subject to some limit due to high-cost, poor cohesiveness and poor film-forming property. Many efforts have been made to resolve these problems; presently polyacrylate is used to copolymerization. This copolymer not only overcomes such flaws, but also creates many new properties of the composite materials. In recent years, many methods have been reporting in literature with the study of copolymer. As a result, the purpose of this paper is to review with some details the primary methods.

Introduction and Application of the Portlet-Based Grid Portal

CHEN Zhi-Ling, CHEN Gang

2006, 23 (4): 442-446. DOI: 10.7523/j.issn.2095-6134.2006.4.002

Abstract ( 1115 ) PDF (KB) ( 0 )

As a web-based application，Grid Portal makes end-users to access the functions and services of Grid easier. The new generation of the Grid Portal bases on Portlet. The Portlet is visual modules which reduce the difficulty and the cost of the Grid Portal development significantly. Moreover, Portlet makes different portals highly compatible and easy migrating. Now the Portlet-based Portals became the mainstream of the new generation of Grid Portal. In this paper the development and the framework design of the Portlet-based Portals were introduced. Then the functions and design of the Grid portal in the YangBaJing cosmic ray observation experiment were discussed.

Simultaneous Stabilization for a Collection of Multi-input Nonlinear Systems

ZHONG Jiang-Hua, CHENG Dai-Zhan

2006, 23 (4): 447-456. DOI: 10.7523/j.issn.2095-6134.2006.4.003

Abstract ( 1308 ) PDF (KB) ( 3 )

This paper considers the problem of designing a controller that simultaneously stabilizes a
collection of multi-input nonlinear systems. Based on the technique of control Lyapunov function, a
sufficient condition for the existence of time-invariant simultaneously stabilizing state feedback controller
is obtained. A universal formula for constructing a continuous controller which simultaneously stabilizes
the systems is derived. The result extends the existing one in [1] for the single-input case.

Numerical Simulation of Falling Film and Droplet Absorption Process over and between Horizontal Tubes in Absorber

WANG Zhao-Liang, TANG Da-Wei

2006, 23 (4): 457-464. DOI: 10.7523/j.issn.2095-6134.2006.4.004

Abstract ( 1225 ) PDF (KB) ( 0 )

A numerical simulation model of falling film and droplet absorption over and between horizontal tubes in absorber is established with consideration of droplet formation and falling process. The solution temperature and concentration distribution, steam absorption rate along the pipes and between the tube bundles are analyzed. The effect of space between tubes on the coupled heat and mass transfer characteristics is made. The results show that the absorption rate due to droplet formation and falling can be up to 30%. The comparison between the calculated and experimental results shows that the numerical simulation is reasonable.

Perturbations Boundary Element Analysis for Transient Flow in Heterogeneous Reservoir

HE Ying-Fu, YIN Hong-Jun

2006, 23 (4): 465-471. DOI: 10.7523/j.issn.2095-6134.2006.4.005

Abstract ( 1290 ) PDF (KB) ( 0 )

The transient flow mathematical model of arbitrary shaped heterogeneous reservoir is constructed in this paper. In order to solve this model, perturbation method is employed and the solution is expanded into a series in powers of perturbation parameter. By using the boundary element method and Duhamel principle, wellbore pressure with effects of skins and wellbore storage is obtained. The type curves are plotted and analyzed considering effects of heterogeneity, arbitrary shape and impermeable barries. At last, the perturbation boundary element method is verified against the analytical solution and is applicable to transient pressure analysis of arbitrary shaped reservoir.

Study on MEA Performance Based on Roughened Nafion117 Membrane

ZHANG Xi-Gui, XIA Bao-Jia, LIU Juan-Ying, WANG Tao, QIN Pei

2006, 23 (4): 472-476. DOI: 10.7523/j.issn.2095-6134.2006.4.006

Abstract ( 1194 ) PDF (KB) ( 0 )

Polarization performance of the MEA fabricated by surface roughening and solvent pre-treating of Nafion117 membrane was improved. Cyclic Voltammetry (CV) and Electrochemical Impedance Spectra(EIS) analysis suggested that the three-phases interface of catalyst/ membrane was expanded and the interface contact impedance was reduced with the roughened Nafion117 membrane as the MEA’s separator.

Urban Industry System for Strategic Environmental Assessment based on Booming Analysis of Early Warning------The case for Dalian City

XU Ling, SHANG Jin-Cheng

2006, 23 (4): 477-483. DOI: 10.7523/j.issn.2095-6134.2006.4.007

Abstract ( 1105 ) PDF (KB) ( 0 )

Considering the faultiness of technique of Strategic Environmental Assessment, a method, Booming Analysis of Early Warning, is introduced into Strategic Environmental Assessment for urban industry system. The environmental and economic actuality of the urban industry system in Dalian is analyzed in this paper. Based upon the rationales and methods of macroeconomics and booming analysis, and considering the running character of the environment and economy of the urban industry system in Dalian, the booming index system of the environment and economy of the urban industry system in Dalian is constructed. After analyzing appraisal results, boom of the environment and economy of the urban industry system in Dalian is discussed. It is concluded that running status of environment and economy system of urban industry system is well in Dalian. However, several indices are on guard. Therefore, booming adjustment of environment and economy on the decision-making must be paid attention, too.

Study on Classification of Agricultural Crop by Hyperspectral Remote Sensing Data

LIU Liang, JIANG Xiao-Guang, LI Xian-Bin, TANG Ling-Li

2006, 23 (4): 484-488. DOI: 10.7523/j.issn.2095-6134.2006.4.008

Abstract ( 1660 ) PDF (KB) ( 0 )

In this paper, taking Shunyi district hyperpectral imagery as an example, we probe into the keypoints and principal procedures for multi-level classification approach and apply this object-oriented method to extracting and mining crops information. Because multi-level classification approach can simplify the complicated information extraction procedure into several relatively easy sub-process, we can intentionally select different characteristic parameters and data mining methods for information extraction in each sub-process according to the feature of the crop we want to discriminate. Consequently, we can make the most of the abundant information in hyperspectral data, and improve the precision of extracted information.

Sources Apportionment of TSP in Chongqing

TAO Jun, CHEN Gang-Cai, ZHONG Chang-Qin

2006, 23 (4): 489-493. DOI: 10.7523/j.issn.2095-6134.2006.4.009

Abstract ( 1278 ) PDF (KB) ( 0 )

Aerosol samples for total suspended particles (TSP) at seven sites and seven kinds of aerosol source samples were collected from 2001 to 2002 in Chongqing. The concentrations of elements, organic carbon, element carbon, water-solubility ions of all particle samples were obtained by chemical analysis method. Source apportionment results derived from the chemical mass balance (CMB) indicated that the major contributors of TSP in Chongqing included: soil/road side dusts (30%), construction dusts (25%), soot dusts (18%), vehicle dusts (10%) and metallurgy dusts (8%), respectively. Moreover, comparison with the results of source apportionment in 1992 in Chongqing showed that major sources of TSP had changed from soot and metallurgy sources in 1992 to multi-pollution sources in 2002.

Analysis on the Sources and Characters of Particles in winter in Taiyuan

LIU Xiao-Lin, WANG Xue-Mei, ZHANG Ren-Jian, ZHANG Huai-De, HU Liang-Wen, ZHU Ling-Yun, SHI Lei

2006, 23 (4): 494-499. DOI: 10.7523/j.issn.2095-6134.2006.4.010

Abstract ( 1465 ) PDF (KB) ( 0 )

Atmospheric particle samples were collected during December at Shanxi in Taiyuan in the winter of 2004 and were analyzed by PIXE which results in 20 element concentrations and elemental distribution. From the observation data of 1983,the element concentrations ,elemental distribution and possible sources of atmospheric distributions of the elements such as Ca , Ti , S , Cu and Pb do not change much, while the size distributions of As、Se、Br have changed to be three peak values modle due to road dust, Al ,V, K and Mn have changed to be fine mode due to anthropogenic sources. The enrichment factors of elements such as Cu、Zn、Br、Pb are very high due to heavy pollutions. Factor analysis further indicated that there are three main sources of Shanxi atmospheric particle concentrations:the soil and dust, metallurgical industry dust, coal combustion dust..

Study on Dietary True Digestible Phosphorus of Growing Pigs

ZHANG Yong-Gang，LI Tie-Jun，HUANG Rui-Lin，YIN Yu-Long， ZHANG Ping，FAN Ming-Zhe，FANG Re-Jun，TANG Hai-Lin，ZHOU Shao-Ru

2006, 23 (4): 500-508. DOI: 10.7523/j.issn.2095-6134.2006.4.011

Abstract ( 1167 ) PDF (KB) ( 0 )

Single factorial randomized-block design was used to study true digestible phosphorus （TdP） requirement of growing pigs by determining growth performance and serum biochemical indexes. Experimental diets were designed five TdP levels, and the ration of total calcium to TdP was 2:1. The experiment results indicated that (1) we got the equation which was about the variety of ADG of growing pigs along with dietary TdP concentration. (2) The equation describing the relationship between F/G and dietary TDP concentration also was educed; (3) Another equation was educed according to the relationship of serum phosphorus concentration and dietary TdP concentration; (4) The serum ALP activity was falling continually with the rise of dietary true digestible phosphorus concentration (P＞0.05); (5) Serum calcium concentration was influenced by dietary true digestible phosphorus concentration hardly, and the variety trend of serum calcium concentration was accord with serum phosphorus concentration influenced by dietary TdP concentration. It was concluded that the dietary TdP requirement of growing pigs was 0.34% and total Ca requirement was0.68%.

The Response of Some Physiological and Biochemical Properties of Leaves of Pyrus bretschneideri Rehd. to Infected by Epitrimerus pyri (Nalepa)

CHEN Ying-Wu, DOU Cai-Hong, ZHANG Xin-Hu, LI Xin-Rong

2006, 23 (4): 509-513. DOI: 10.7523/j.issn.2095-6134.2006.4.012

Abstract ( 1257 ) PDF (KB) ( 0 )

Several physiological and biochemical indexes of leaves of Pyrus bretschneideri Rehd injured by Epitrimerus pyri (Nalepa) were measured. The results showed that, comparied with the normal leaves, the chlorophyll and soluble sugar of the infested leaves decreased by 50.05% and 19.86% respectively; and the soluble protein ,free amino acid， free proline, the activity of hydrogen peroxidase and the membrane permeability of the infested leaves increased by 29.17%, 21.59%,107.03%, 22.62% and 150.43% respectively by the means of the analysis of spectrum, chemistry and electric physics.

A Fast Super-Resolution Reconstruction Algorithm

YUAN Jian-Hua, YIN Xue-Min, ZOU Mou-Yan

2006, 23 (4): 514-519. DOI: 10.7523/j.issn.2095-6134.2006.4.013

Abstract ( 1364 ) PDF (KB) ( 0 )

In this paper, we derive a fast super-resolution reconstruction algorithm. The new algorithm is non-iterative, it needs the FFT algorithm and the inverse of little-size matrices. The method is extended to find the regularization parameter through the GCV algorithm.

The Traffic Network Time-Space Division of Dynamic Traffic Assignment

LI Run-Mei, GONG Xiao-Yan

2006, 23 (4): 520-526. DOI: 10.7523/j.issn.2095-6134.2006.4.014

Abstract ( 1080 ) PDF (KB) ( 0 )

In this paper, a new concept of assignmentability is proposed. The concept is used to assess the efficacy of the dynamic traffic assignment on road networks and also used to be the principle of network time-space division of dynamic traffic assignment. The characteristics of traffic flows are researched not only on space but also on time. At last, the course of dynamic time-space division of traffic network is given. The study provides a rational object for dynamic traffic assignment modeling.

Selection Method for AVL Tree Rebalancing

ZHU Yu, ZHANG Hong-Bin

2006, 23 (4): 527-533. DOI: 10.7523/j.issn.2095-6134.2006.4.015

Abstract ( 1313 ) PDF (KB) ( 0 )

The traditional algorithm for AVL tree rebalancing is the rotation method, which uses methods of left-rotation, right-rotation, left first rotation then right and right first rotation then left to deal with the different unbalance structures respectively. In fact, it is more simple to solve imbalance using the obvious characteristic of AVL tree that "middle for the root, smaller for the left and bigger for the right", and the balance-factors can be found directly. Based on this idea we propose the selection method, which chooses the smaller, middle and bigger nodes from the unbalanced structure and reform them to that balanced state. We have a symmetry analyzation and description on both inserting and deleting. The whole algorithm is non-recursion. Our experimental result verifies that the construction time of the selection method decreases over 20% than that of the rotation method and the destruction time decreases over 13% when the number of nodes exceeds 100,000.

An Analyse of Packet Sampling Strategy of Network-based Intrusion Detection System

WANG Wei-Ping, ZHU Wei-Wei, CHEN Wen-Hui, LIANG Liang

2006, 23 (4): 534-542. DOI: 10.7523/j.issn.2095-6134.2006.4.016

Abstract ( 1204 ) PDF (KB) ( 0 )

Intrusion detection is an important part of the information security research, and the network-based intrusion detection system accomplish the detection by examine the network packets. Since sampling entails incurring network costs for real-time packet sampling and packet examination hardware, we would like to develop a network packet sampling strategy to effectively detect network intrusions while not exceeding the velocity of the packet examination. We consider this problem in a game theoretic framework and introduce sampling schemes that are optimal in this game theoretic setting by the Minimax theorem and the max-flow min-cut theorem. According to the limitation and scarcity of this single intrusion node method, We introduce a method of risk management and extend the solution to more complex cases to solve the choice of sampling strategy while facing more various environments. At last, we provide an empirical study to exemplify our improved method.

Research in the Method of Population Estimation in Urban District Based on EO data

YANG Si-Quan, LIU Hua

2006, 23 (4): 543-547. DOI: 10.7523/j.issn.2095-6134.2006.4.017

Abstract ( 1190 ) PDF (KB) ( 0 )

In this paper, a method to estimate population in urban district by using EO (Earth Observation) data has been studied and discussed. Firstly, residential district has been classified into three kinds，which are high-dense, middle-dense and low-dense, according to the investigation, and the area of each kind of district has been calculated by interpreting IKONOS. Then, the correlation between population and residential area has been studied by using linear analysis, and an equation showing the correlation between population and residential area has been determined. At last, the equation between population and residential area has been tested. Results show: it is a reasonable and adoptable way to estimate population by using EO data in some emergent situation in urban district.

Photosynthetic Characteristics of Quercus Mongolica in Region of Changbai Mountain

WU Jia-Bing, GUAN De-Xin, ZHANG Mi, SHI Ting-Ting, HAN Shi-Jie, JIN Chang-Jie

2006, 23 (4): 548-554. DOI: 10.7523/j.issn.2095-6134.2006.4.018

Abstract ( 1520 ) PDF (KB) ( 0 )

he Photosynthetic characteristics of Quercus mongolica were studies based on the measurement of leaves photosynthesis under artificial controlled conditions of light intensities and CO2 concentration in region of Changbai Mountain. For mature trees, the light compensation point (Lcp), light saturation point (Lsp) and apparent quantum efficiency (α) were 21μmol/m2/s, 1564μmol/m2/s and 0.045μmol/mol, respectively. For young trees, the values of Lcp, Lsp, α, and CO2 compensation point, CO2 saturation point were 29μmol/m2/s, 1581μmol/m2/s, 0.049μmol/mol, 73μmol/mol, 625μmol/mol, respectively. The photosynthesis assimilation of young trees was more active than mature trees. It suggested that the Quercus mongolica was intrinsically helophytic plant, but the use efficiency of light quantum was low in strong light condition. The results also showed that the diurnal variations of net photosynthetic rate of young trees assume a typical midday depression pattern. Strong light intensity and high VPD were the key influencing factors.

Design Principles of Fair Exchange Protocol

WANG Zhi-Ling, ZHANG Yu-Qing, YANG Bo

2006, 23 (4): 555-560. DOI: 10.7523/j.issn.2095-6134.2006.4.019

Abstract ( 1424 ) PDF (KB) ( 0 )

Fair exchange protocols are different from classical security protocols, which resulted in the differences in design principles between them. Therefore, when designing fair exchange protocol, the designer needs to reconsider some other factors. Based on the characteristics of fair exchange protocols, in this paper, the authors put forward four new design principles. In order to illuminate the importance of these principles, the authors give some attack examples. With these principles, the designer can consider the various possible vulnerabilities and errors at the beginning of fair exchange protocol design. Therefore, the quality of protocol design is improved greatly.

Spatial and Seasonal Variability of Methane Emission from Natural Wetlands

DING Wei-Xin, CAI Zu-Cong

2006, 23 (4): 561-568. DOI: 10.7523/j.issn.2095-6134.2006.4.020

Abstract ( 1360 ) PDF (KB) ( 0 )

Spatial and seasonal variabilities in methane emission from natural wetlands in the Sanjiang Plain, China were studied in the years 2001-2002 and the factors influencing methane emission were also evaluated. A seasonal variability of methane emission that increased with plant growth, reached maximum in August and then decreased was identified in freshwater marshes. This pattern was mainly affected by temperature and depth of standing water. Low methane emission at the early growth stage was due to low temperature rather than deficiency of substrate for methane production. Low temperature not only reduced directly methane production but also lowered the activity of aerobic microbes; the latter in turn left more oxygen in the rhizosphere for methanotrophs resulting in more methane to be oxidized. Methane emission in the freshwater marsh showed the following order: Carex lasiocarpa > Carex myeriana > Deyeuxia angustifolia. The Carex plants transported 72-86% of total methane emission, but only 28-31% for Deyeuxia angustifolia. Carex lasiocarpa accentuated methane oxidation rather than methane production in the rhizopshere and by contrast, Deyeuxia angustifolia stimulated methane production by excreting root exudates instead of methane oxidation by releasing oxygen. The higher methane concentration in porewater in the Carex lasiocarpa marsh than in Deyeuxia angustifolia marsh was mainly because of the deep standing water, which inundated more plant litters resulting in more organic carbon to be provided for methane production.

A Preliminary Study for Basic Approaches in Artificial Transportation Systems

TANG Shu-Ming, WANG Fei-Yue

2006, 23 (4): 569-575. DOI: 10.7523/j.issn.2095-6134.2006.4.021

Abstract ( 1714 ) PDF (KB) ( 0 )

This paper discusses basic approaches in artificial transportation systems. It starts a survey on the current developments of traffic simulation systems, addresses the ineffectiveness of the top-down reductionism in conventional traffic simulation methods, and proposes an effective tool of bottom-up holism artificial transportation systems to solve the problems of complex transportations systems. The main subject here will be metropolitan transportation systems that take both metropolitan logistics and ecosystems into consideration. We will adopt a bottom-up agent-based technology to build models and management and control strategies for metropolitan transportation, logistics and ecosystems. Meanwhile, we will also integrate artificial societies, computational experiments, parallel systems, traffic level of service index, and the hall for workshop of metasynthetic engineering from qualitative to quantitative analysis to find effective solutions to problems in metropolitan transportation, logistics and ecosystems and build a new approach and framework to facilitate integrated, coordinated, and sustainable development of metropolitan systems under the principle of continuous investigation and improvement.

Current Issue