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Table of Content

    25 August 2015, Volume 54 Issue 4
    A Review of Evaluation of External Costs in Road Transport
    CAI Ming;ZHOU Zhanhong
    2015, 54(4):  1-7. 
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    External costs in road transport are important indicators that evaluate the impacts on bystanders brought by road transport activities. They play significant roles in assessing comprehensive value of road transport infrastructures and policies. By reviewing the advanced literature of evaluation of external costs in road transport, the evaluation methods of external congestion cost, external accident cost, air pollution cost, noise cost and global warming cost in road transport are summarized systematically. Then, the advantages, disadvantages and applicability of different evaluation methods of each external cost are analyzed in detail. At last, the emphases and difficulties of conducting evaluation of exteranl costs in road transport are discussed and some suggestions about carring out evaluation study of external costs in road transport in Chinese urban area are offered. In these suggestions, the actuality of evaluation research of external costs in road transport in China is taken into account.

    A High Order Symplectic Algorithm Based on Weighted Residual Method
    LU Kelang;FU Minghui;LI Weihua; LI Renfei
    2015, 54(4):  8-12. 
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    A new way to construct high order symplectic algorithms is proposed based on weighted residual method. Firstly, in the time subdomain, the corresponding integral equation of Galerkin method for Hamilton dual equation based on the idea of weighted residual method is proposed, then the generalized displacement and momentum are approximated by the same Lagrange interpolation within the time subdomain, which are substituted into the corresponding integral equation. By numerical integration, the original initial value problem of dynamics is expressed as algebraic equations with displacement and momentum at the interpolation points as unknown variables. For nonlinear dynamic systems, a simple scheme of choosing initial values, which can significantly improve the computational efficiency for NewtonRaphson method, is presented. Finally, the symplecticity and performance of the proposed algorithms are discussed in detail. Compared with the same order symplectic RungeKutta methods, the accuracy of the two methods are almost the same, but the proposed algorithms are much simpler and less computational expense. The numerical results illustrate that the proposed algorithms show good performance in accuracy and efficiency.

    Comparative Analysis of Vortex-Induced Vibration of Submerged Floating Tunnel Tether under Two Different Boundary Conditions
    LIU Bin; LIU Zuoqiu;WU Zhiwen
    2015, 54(4):  13-18. 
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    In order to analyze the vibration stability of submerged floating tunnel tether under two different boundary conditions, the vibration equation of tether was set up. The equation was simplified by Galerkin method. The vibration stability of tether was judged by Lyapunov exponent method. Effects of damping ratio , bending stiffness and span of tether , current velocity and vortex-induced frequency on vibration stability of tether were analyzed and compared under different boundary conditions. It may be concluded that  tether is been gradually from stable state to unstable state as the current velocity increases under two different boundary conditions. The tether tends to be stable as the damping ratio, bending stiffness of tether increases, when the vortex-induced frequency  under two different boundary conditions is close to the tether. It will occur vortex-induced resonance and the tether is easy to be unstable, and the unstable region expands gradually as the current velocity increases under two different boundary conditions, but the unstable region is larger which under the combination sliding boundary.

    Structural Damage Identification Based on Cuckoo Search Algorithm
    XU Haojie;LIU Jike; Lv Zhongrong
    2015, 54(4):  19-22. 
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    Cuckoo search (CS) algorithm is an emerging approach to solve structural damage detection . By utilizing the modal assurance criteria(MAC),the objective function of the certain structure is built. Then the CS algorithm is adopted to solve the certian objective function to achieve the damage location and extent of the system. A dual-span beam and a truss are uesd as numerical simulation cases to prove the validity of the CS algorithm. The simulation results show that the CS algorithm is efficient and accurate even under measurement noise.

    Parameter Optimization of Agent PID Motion Controller Based on Pole Assignment
    ZHANG Guanglei;QI Hong;JIA Heming
    2015, 54(4):  23-28. 
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    Aimed at the problem of motion control of intelligent agent, the surface ship anti rolling was taken as an example with using the classical PID controller,  which is easy to implement in engineering. A kind of accumulation and the performance indexes of the absolute error in time by the roll and yaw of the simplex optimization algorithm were proposed to solve the controller parameters optimization positive problem According to the actual system output,  the controller parameters  were deried  for the optimization of the basis. The optimal roll and yaw control was ultimately achieved, and  the practicability of the proposed controller was gratly improved. At the same time,due to the difference between the frequency characteristics of the roll and yaw,  the high pass filter has better solved the rudder roll stabilization of course impact problem. The simulation results illustrated that the controller parameters of the simplex algorithm optimization of the control effect increased with the high pass filter and reduced the impact on the course of the rudder roll stabilization.

    Research on Small-Scale Flame Propagation Combustion Mechanism
    QU Zhongwei;YAN Shilong;MA Honghao
    2015, 54(4):  29-36. 
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    Using a combination of experimental and numerical simulation methods to study the premixed gas deflagration flame propagation in the flat slit. In this paper, the use of high-speed digital camera system for catching the propagation principle, and the result shows that the extinguish length and the critical flame propagation speed displays approximately linear when there is a certain slot height. By studying the intrinsic link of the propagation exothermic chemical reaction, Wall heat dissipation and so on with the flame propagation and extinguish states, looking the inherent propagation and extinguish laws of premixed flame propagation in a flat slit. Judging whether the flame quenching slit to provide a reference.To provide theoretical support for the selection and design of the flame arrester core .

    Noether Quasi-Symmetry for Nonconservative Mechanical System in Phase Space Based on Fractional Models
    HE Shengxin, ZHU Jianqing
    2015, 54(4):  37-42. 
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    The fractional Noether symmetries and fractional conserved quantities for a non-conservative system in phase space are proposed and discussed. Firstly, the fractional Hamilton canonical equations for the non-conservative system are established. Secondly, based upon the invariance of the fractional Hamilton action under the infinitesimal transformations of group, the definitions and criterion of fractional Noether quasi-symmetric transformations are obtained, then the relationship between a fractional Noether symmetry and a fractional conserved quantity of nonconservative system in phase space is established, and the fractional conserved quantity is obtained. Finally, the special cases, which the generalized nonpotential forces are not exit or the gauge function is equal to zero, are discussed. At the end, two examples are given to illustrate the application of the results.

    Oscillation of Half-Linear Fractional Impulsive Differential Equations
    LU Wei;GAO Jie;WANG Qunfang
    2015, 54(4):  43-48. 
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    The oscillation for a class of semi-linear fractional impulsive differential equations with damping is studied. By means of the impulsive inequality and the generalized Riccati transformation, some new oscillation criteria are obtained for all solutions to the equation. An example is given to illustrate the results. This is the generalization of the application of Riccati technique in new field.

    The Model of Checking Method Based on  Improved Computation Tree Logic Possibility Measure
    CHEN Yansheng;ZHANG Zanbo;WU Zhongkun;REN Jiangtao
    2015, 54(4):  49-54. 
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    To settle various problems in computation tree logic possibility measure model validation process, such as high time complexity and low efficiency performance. The I-PM_CTL algorithm is proposed. The algorithm is based on the traditional model checking mark algorithm, so that it is adaptable to the need of mark detection of large-scale, highly complex formulas. The steps of the algorithm are as follows. Fristly, the logic tree formulas are calculated using relevant possibility measure, which is a preprocessing step to identify the uniqueness of the common sub-expressions. Secondly, it specifies the state of common sub-expressions and I-PM_CTL model, while maintaining the equilibrium of model checking space. Finally, this algorithm implements the verification, ensuring the I-PM_CTL formulas  verification to be completed in one time with high probability. The results of simulation experiments show that the IPM_CTL algorithm not only effectively reduces time complexity, but also improves the verification performance.

    Qualitative Analysis and Numerical Simulation of Positive Solutions for a Predator-Prey Model
    WANG Lijuan,JIANG Hongling
    2015, 54(4):  55-62. 
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    The steady state positive solutions of a predator-prey model with diffusion are studied. A priori estimate for positive solutions is obtained by using maximum principle. Applying to the local bifurcation theory, the existence of local bifurcation solutions is given. It follows from the global bifurcation theory that the local bifurcation solution can be extended to global bifurcation solution and the trend is obtained. Then a necessary and sufficient condition for the existence of positive solutions is obtained. By the stability theory, the stability of local bifurcation solutions is investigated. Finally, the theoretical results are verified and complemented by the numerical simulation.

    Oscillation of Higher Order Emden-Fowler Functional Differential Equations with Damping
    YANG Jiashan;QIN Xuewen
    2015, 54(4):  63-68. 
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    In order to develop and improve the theory about oscillation of functional differential equations, oscillatory behavior of a class of higher-order nonlinear variable delay Emden-Fowler functional differential equations with damping is studied. By using the generalized Riccati transformation, the H-lder inequality and some necessary analytic techniques, some new criteria for the oscillation of the equations are proposed. These criteria improve and generalize some corresponding known results. Some examples are given to illustrate the importance of the results.

    On Some New Upper Bounds of Domination Numbers in Graphs
    XU Baogen;LI Chunhua;FAN Zhizhu
    2015, 54(4):  69-71. 
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    Let G=(V,E) be a graph, a subset DV is said to be a dominating set of G if v∈V-D, there exists u∈V such that uv∈E. The domination number of G is defined as the minimum value of |D| taken over all dominating set D of G. By the method of choosing vertex domination, some important results on domination number of a graph are obtained, some new upper bounds of domination numbers in graphs are given, and some known results are generalized.

    Ruin Probability of Surrender Dependent Multi-Type Risk Model in Sparse Process
    WEI Jing;GE Shigang;LIU Haisheng
    2015, 54(4):  72-74. 
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    With the diversity of insurance business, the process of risk model by describing with single risk has limitation. So multi-type insurance risk model is particularly necessary. Considering the possibility of premium randomness and surrender risk, a multitype random risk model is established with the times of premium and claim being Poisson processes, and the surrender being a random q-sparse process of the premium process. By analyzing the properties of the surplus process, it is obtained the expression of ultimate ruin probability and the Lundberg inequality for ruin probability upper bound.

    The Secondary Metabolites of the Crinoid(Comanthina schlegeli)  Epipsymbiosis Fungus Alternaria brassicae 93
    LI Yongfang;WANG Hongwei;XU Jiayi;LI Jing;LIU Lan
    2015, 54(4):  75-78. 
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    Secondary metabolities of the crinoid epipsymbiosis fungus Altermaria brassicae 93 from South China Sea were studied. The metabolities of Alternaria brassicae 93 were isolated by silica gel column chromatography,Sephadex LH-20 gel column chromatography and HPLC, the structures of compounds were eventually identified and confirmed on the basis of physicochemical properties, spectral data and compared with the published spectral information. Five compounds were isolated from marine fungi for the first time and their structures were identified as clavatol(1),3R,14S-ochratoxin A(2),3R,14S-ochratoxin B(3),chaetoquadrin F(4) and entcycloechinulin(5).

    Synthesis of A Series of Substituted 2-Amino-2′-Hydroxy-1,1′-Binaphthyl Compounds Catalyzed by Copper-Amine Complex
    CHEN Zhipeng, LIU Shuwen
    2015, 54(4):  79-83. 
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    A serious of substituted NOBIN compounds were synthesized from substituted 2-naphthol and 2-naphthylamine in methanol solvent at room temperature, using the CuCl2·2H2O/benzylamine complex with molar ratio of 1∶4 as a catalyst. The product with mediate yields was purified by precipitation. The chemical structure was characterized using NMR spectroscopy and FAB-MS analysis.

    Secondary Metabolites of Endophytic Cladosporium sp.J6 from Endangered Chrysosplenium carnosum
    MA Yanhong;JIANG Siping;XU Aiguo;PUBU Duoji;CHEN Bin;WANG Jun
    2015, 54(4):  84-86. 
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    To study the secondary metabolites of endophytic Cladosporium sp.J6 from endangered Chrysosplenium carnosum from Tibet. The chemical constituents were isolated and purified by silica gel, Sephadex LH-20, ODS-18 column chromatography, and HPLC; their structures were identified by NMR and MS analysis, or comparison with literatures. Five compounds were isolated from the fermentation products of Cladosporium sp.J6; their structures were identified as alternariol (1), alternariol 5-O-methyl ether (2), β-carboline (3), uracil (4), and uridine (5). This report was about secondary metabolites of endophytic fungus from Chrysosplenium Tourn. ex L. for the first time.

    DFT Investigation of the Adsorption of CO, N2O and NH3 Gases On  (Cu,N)/TiO2(001)
    WANG Xia;YANG Xiaohong;LI Xiugang; XUE Xishi
    2015, 54(4):  87-92. 
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    The adsorption energies ΔEads of CO, NO2 and NH3 gases on the anatase TiO2(001) surface, which co-doped by Cu and N atoms, were obtained while the strongest adsorption energies and optimized structures were given out by the density functional method. Through analysis of the PDOS, the adsorption mechanisms were given out. All the adsorptions of the studied gases on the anatase (Cu,N)/TiO2 (001) surfaces were compared with the former experiments and other calculations.

    Synthesis and Fluorescence Properties of Quinolinone-Based Rare Earth Complexes
    WANG Huizhen;YANG Weiqing;YANG Haijun;ZHANG Junqing;LIU Yuejia
    2015, 54(4):  93-98. 
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    Quinolinonebased rare earth complexes were synthesized from carboxylic acid derivatives of quinolinone (1). Their structures were characterized by FTIR, TG, MS analyses, and the complexes were determined to be [Ln(C16H15N3O6)X]·nH2O (Ln=Ce,Tb). The fluorescence properties of complexes and compound 1 were investigated. The result showed that the fluorescence intensity of cerium complex (2)〗 was 3.0 times as the compound 1. Meanwhile,the maximum fluorescence emission wavelength of complex 2 exhibited red shift (46 nm) compared to that of compound 1. The maximum fluorescence emission wavelength of terbium complex (3) exhibited red shift (46 nm) compared to that of compound 1. The peak pattern of the two lanthanide metal complexes was superior compared to that of compound 1 and metal ions. On the base of these results,the complexes have a good application prospect in optoelectronic field, and are significant to the technological development in biological detection and fluorescence imaging.

    Secondary Metabolites of Mangrove Endophytic Fungus Aspergillus sp.9H in the South China Sea
    WANG Yanlei;LAN Xiong;HUANG Huarong; ZHANG Kun
    2015, 54(4):  99-101. 
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    Seven compounds, including brefeldin A (1), methoxyvermistatin (2), 6-demethylvermistatin (3), purpurester A (4), and glycerollhendecanoate (5), were isolated from the mangrove endophytic fungus Aspergillus sp. 9H, obtained from the Kandeliacandel (Linn.) Druce, collected from Yangjiang, Guangdong. Their structures were identified through mass analysis and NMR spectroscopy. Compounds 2,4,5 were isolated from marine fungus Aspergillus sp. for the first time.

    Mangrove Community Classification Based on WorldView-2 Image and SVM Method
    TANG Huanli;LIU Kai;ZHU Yuanhui;WANG Shugong;LIU Lin;SONG Sha
    2015, 54(4):  102-111. 
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    Using remote sensing technology in Mangrove Community Classification is very significant for surveying, taking advantage of and protecting Mangrove resource. In this study, based on the spectrum characteristics of mangroves, vegetation index and texture information calculated from WorldView-2 satellite imagery, we used object-oriented classification method, SVM (Support Vector Machine), in conjunction with field surveys to map mangrove forest at communities-level in Daweiwan District, Qi'ao Island, Zhuhai. The single-scale and multi-scale classification were also compared. The results indicated that WorldView-2 data, a very high-resolution satellite remote sensing imagery with 8 bands are very suitable for mangrove forest classification using objectoriented and SVM method. The overall accuracy and Kappa indices for mangrove forest classification at the species level in the study area were 84.2% and 0.794 for multi-scaled analysis and 69.8% and 0.616 for the single-scaled.

    Morphology and Genetic Diversity Analysis of Pelteobagrus fulvidraco Populations in Zhujiang River
    XIE Tanghui, ZHAO Huihong;YANG Huirong;LIU Li;HAN Xingpeng;YANG Xiankuang;CHEN Yibin;LIU Lijie
    2015, 54(4):  112-120. 
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    Genetic differences of Pelteobagrus fulvidraco populations from Zhujiang River were compared by morphological and molecular biological methods. The scatter diagram of principal component analysis revealed that the populations from Duliujiang River and Lijiang River pooled into one group, while those from Dongjiang River separated from Duliujiang River and Lijiang River. It indicated that Dongjiang River population had a certain morphological differentiations compared to other two populations,while there were few morphological differentiation between Duliujiang River and Lijiang River.The mtDNA D-loop sequence analysis of three populations showed that 176 variable sites and 36 haploid types were detected, there were similar base compositions among three populations, the content of A + T (59.6%) was higher than the content of G + C (40.4%), the average gene flow was 3.234, there was a large gene exchange between three populations.The NJ tree of haploid type shows that the populations Lijiang River and Duliujiang River formed the first cluster which together with the populations from Dongjiang River formed the second cluster. The analyzed result of 21 microsatellite loci in three populations showed that 15 loci were high polymorphic(PIC>0.5),the clustering result of three populations was in accordance with the result of mtDNA D-loop marker, all clustering results had a certain correlation with their geographical distribution. From the result of morphological and molecular analysis,a conclusion can be drawn that the morphology in three populations had certain difference,there was rich genetic diversity among populations.

    Structural Characteristics of Dissolved Organic Matter in the Rhizosphere Soil of Water Spinach Cultivars Differing in Cd Accumulation
    GONG Yulian;YANG Zhongyi;CHEN Aikui;ZENG Xiaolong;ZENG Bijian;WANG Pingjie;TANG Yuwei
    2015, 54(4):  121-126. 
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    Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (1H NMR and 13C NMR) were used to investigate the structural characteristics of dissolved organic matter (DOM) in the rhizosphere soil of a low-Cd cultivar (QLQ) and a high-Cd cultivar (T308) of water spinach (Ipomoea aquatica Forsk.). The results showed that carbohydrates were the main components of DOM in the rhizosphere soil of the two cultivars, and the contents of alkyl and aromatic substances were relatively low. There were obvious differences in the structural characteristics of DOM between the two cultivars. The relative contents of carboxylic C and longchain aliphatic C of DOM in the rhizosphere soil of QLQ were lower than those of T308, but that of aromatic substance of QLQ was higher. Alkyl substance of DOM in the rhizosphere soil of QLQ possessed the characteristics of relatively high content,short branched chain and high branched chain. Although carbohydrate H content of DOM in the rhizosphere soil of QLQ was lower than that of T308, carbohydrate C content was higher than that of T308, which suggested that there might be differences in the structure of carbohydrates of DOM in the rhizosphere soil between the cultivars. The results indicated that the structural characteristics of DOM in the rhizosphere soil of the low-Cd cultivar might influence Cd behavior and bioavailability, leading to relatively low ability to activate soil Cd, which would be associated with its low Cd accumulation.

    A New Species of Eurya (Theaceae) from Yunnan,China
    SHI Xianggang ;YE Chuangxing
    2015, 54(4):  127-128. 
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    Eurya makuanica Ye Chuangxing et Shi xianggang, a new species of Theaceae, from Yunnan, China, is described and illustrated. It is morphologically similar to E. wuliangshanensis Ming, but differs from the latter by the following characteristics: leaves thinly leathery to papery (vs leathery in E.wuliangshanensis), leaves blade ovateelliptic (vs oblong), apex caudate (vs acuminate), secondary veins obviously impressed above (vs slightly raised); sepals and petals suborbicular (vs ovate). The new species is rare and currently only known in the mountain nearby kashang forest farms in Yunnan province.

    Spatiotemporal Variations of Extreme Temperature Events over Xinjiang during 1961-2010
    CI Hui;ZHANG Qiang;ZHANG Jianghui;BAI Yungang
    2015, 54(4):  129-138. 
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    Spatiotemporal variations of extreme temperature events in Xinjiang have been analyzed based on daily average temperature, daily maximum temperature and daily minimum temperature data from 50 meteorological stations covering the period from 1961 to 2010 using statistical methods and 22 extreme temperature indices commonly used in extreme climate events researches. Daily temperature and mean annual temperature in Xinjiang increased significantly after 1996, minimum temperature in winter and summer rose significantly, and the warming magnitude in winter was greater than in summer. Except for GTmax, GTavg, DTR and TXx, TNx, TXn, TNn, all cold and warm indices are characterized by significant downward and upward trends respectively in the late 1990s. Overall, the magnitudes of warming tendency of cold indices, low temperature indices, night indices are obviously greater than those of warm indices, high temperature indices and day indices,and they are greater in basins than in mountains. The mutation of trend analysis of extreme cold indices occurred in the midandlate 1980s, and that of extreme warm indices occurred in the late 1990s. The warming tendency can be checked obviously no matter with average temperature indicators or changes of extreme temperature indices. Average temperature (GTavg) and maximum temperature (GTmax) during growing season are characterized by an upward trend. The increase of daily average temperature will enhance the intensity of heat wave days (HWDI) and lengthen the growing season. Growing season length is longer in southern Xinjiang than in the northern and eastern Xinjiang, and it is longer in basins than in mountains.

    Analysis of Mineralogical Composition and Texture to Quantify the Mechanical Properties of Red Bed Soft Rock#br# ——A Case Study of Leipi Rock at World Heritage Site, Mt. Langshan in Hunan Province
    CHEN Zhi ;PENG Hua;GREIF Vladimir;YAN Luobin ;SIMONSON Scott;MA Ru
    2015, 54(4):  139-149. 
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    This study focuses on the mineralogical composition and texture of redbed soft rock. On the basis of the statistical analysis of the redbed soft rock characteristics, such as the composition, grain size observed under polarized light microscope, the effects of composition and texture on the mechanical properties were discussed respectively. The study on rock samples has shown that: ① the compressive strength and modulus of elasticity show a rising trend with the increase of mineralogy content and grain size; ② as average grain size increases, its compressive strength and modulus of elasticity become stronger accordingly. When the average grain size reaches a numerical range (diameter is about 025 mm), the compressive strength and modulus of elasticity would bump up at the same time, according to which we can speculate that mineralogical composition has a bigger effect on the mechanical properties than the grain size.

    Improving Bus Stop Redundancy Using Tabu Search Algorithm and SIC Model
    YANG Nana;ZHANG Qingnian;HUANG Jianfeng
    2015, 54(4):  150-157. 
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    The number of bus stops is a key factor for transit accessibility and system efficiency. Adding more stops along a route will increase coverage of potential riders, but slow down travel speeds, and then decrease system efficiency. The purpose of this study is to identify redundant stops and improve the quality of public transit services. We successfully integrate the tabu search algorithm (TS) and a GIS spatial optimization model called spatial interaction coverage (SIC) model to address this problem. This method can easily identify redundant stops without reducing the interaction between the demand areas and the transit facilities. In addition, a stop coverage ratio index (SCRI) is introduced as one of the indicators to access the attraction of the transit facilities. The proposed method has been tested in a bus route of Dongguan, China. The comparison experiment indicates that TS has better performance than SA especially in the computing time for bus stop selection. We believe that this method can be used as a planning tool to help traffic planners to improve public transit efficiency.

    The Influence of Atmospheric Boundary Layer -Structure on PM2.5  Concentration Over Dongguan Region
    WU Meng;WU Dui;FAN Shaojia;LIAO Zhiheng;FAN Qi
    2015, 54(4):  158-163. 
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    Based on the observational wind profile data, temperature sounding data and the hourly PM2.5 concentration data from the boundary layer observation experiment in Dongguan region during December 2013, the influence of atmospheric boundary layer structure on PM2.5 concentration in Dongguan region has been discussed. It was found that the PM2.5 air pollution weather occurred in winter of Dongguan region was mostly influenced by the weather system of weak southward moving cold air. Under the control of continental cold high, the evolution of atmospheric boundary layer structure was very typical. During the PM2.5 air pollution situation, the daily mean height of mixing layer in daytime was lower than 600 m sometimes, the pollutants accumulated persistently and its concentration increased gradually with the low atmospheric boundary layer height. The height of stable boundary layer in nighttime was about 100 m. By reason of the law height of stable boundary layer in nighttime, the peak PM2.5 concentration occurred in nighttime. The vertical wind field of Dongguan region had obvious three layer construction. The lower layer with slow wind speed made the pollutants accumulate inside atmospheric boundary layer and hard to diffuse. The middle layer which appeared in a very low height with slow wind speed gave rise to the pollutants be compression inside lower layer further. Under the control of continental cold high in winter, the inversion layer appeared frequently in Dongguan region during PM2.5 air pollution situation. The height of low altitude inversion base was about 700 m with a large thickness and intensity; the surface inversion occurred in nighttime frequently with a thickness of about 100 m.

    Region Difference of Economic Development in Guangdong Province Based on Spatial Statistical Analysis
    LI Hangfei
    2015, 54(4):  164-170. 
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    This paper takes 21 regions in Guangdong province as research object,and uses the index of per capita GDP to analyse spatialtemporal evolution of the economic development during 2000-2012 and 2018 in Guangdong Province by means of grey prediction,spatial autocorrelation and spatial regression. The characteristic of global spatial autocorrelation of the economic development level of different regions in Guangdong is obvious and the region difference of economic development in Guangdong is relatively small. The spatial pattern of region economic development in Guangdong is stable and the spatial difference is relatively small. The local spatial autocorrelation of the economic development level of different regions in Guangdong is not obvious and different gather centers have been formed. The spatial difference of economic development is influenced mainly by economic structure,urbanization economic development level and human resources.