最新刊期
      卷 59 ， 期 1 ， 2020
      • Vol. 59, Issue 1, Pages: 1-8(2020) DOI: 10.13471/j.cnki.acta.snus.2020.01.001
        摘要：A brief introduction of Landau-Ginzburg A model (LG Amodel) in homological mirror symmetry is given. Firstly, a short review of the general picture of the homological mirror symmetry is given. Then the background of Landau-Ginzburg model and its role in homological mirror symmetry are discussed. Finally,  a brief introduction of our recent work on the Fukaya category of LG model is included. Both mathematical and physical backgrounds are tried to include in this introduction as much as posible.  
        关键词：Fukaya category;Landau-Ginzburg model   
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      • ZHANG Chunxia
        Vol. 59, Issue 1, Pages: 9-14(2020) DOI: 10.13471/j.cnki.acta.snus.2020.01.002
        摘要：The relative and generalized Tate cohomology with respect to balanced pairs are studied. An Avramov-Martsinkovsky type exact sequence is obtained.  
        关键词：balanced pair;relative cohomology;generalized Tate cohomology;Avramov-Martsinkovsky type exact sequence   
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      • GAO Zhizhong
        Vol. 59, Issue 1, Pages: 15-23(2020) DOI: 10.13471/j.cnki.acta.snus.2020.01.003
        摘要：In order to generate complex hyperchaotic, a new fourdimensional Tang hyperchaotic system based on Tang system is built. The phase diagram，bifurcation diagram and Lyapunov exponents spectrum diagram of the system are analyzed by means of numerical simulations．Numerical simulations show that the new systems dynamics behavior can be periodic, quasiperiodic, chaotic and hyperchaotic as the parameter varies. Compared to the previous hyperchaotic, the system possess the large change range with new parameterskand the system changes withkandpshow the same dynamic behavior and a certain proportion. Linear controller is designed to realize synchronization of the hyperchaotic system. Results demonstrate that the method is correct and effective. Finally, a corresponding experimental circuit is designed. The hyperchaotic dynamical behavior of the circuit system and synchronization results of the driver system as well as response system are observed by an oscilloscope. The results are basically consistent with those of digital simulation.  
        关键词：novel hyperchaotic system;phase diagram;bifurcation diagram;Lyapunov exponents spectrum;linear feedback synchronization;experimental circuit   
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      • XIAO Longjiang,HUANG Jianliang
        Vol. 59, Issue 1, Pages: 24-34(2020) DOI: 10.13471/j.cnki.acta.snus.2020.01.004
        摘要：This study investigates nonlinear dynamics of a fixedfixed buckled beam with1∶3internal resonance in the first two symmetric modes subject to uniform base harmonic excitation. The Galerkin method is employed to discretize the governing equation, the traditional incremental harmonic balance (IHB) method with single time scale is used to track periodic responses of the buckled beam，and the Floquet theory is used to analyze stability and bifurcation of the solution. It is found that the antisymmetric modes can be excited with increasing the excitation amplitude due to1∶3internal resonance, continuously increasing the excitation amplitude, Hopf bifurcation occurs which leads to quasi-periodic motion whose spectrum contains uniformly spaced sidebands around integer multiples of excitation frequency with increasing the excitation amplitude. The IHB method with two timescales is used to investigate quasi-periodic motion, whose solutions are in good agreement with those from numerical integration using the fourth-order Runge-Kutta method.  
        关键词：buckled beam;internal resonance;quasi-periodic motion;uniformly spaced sidebands;incremental harmonic balance method with two time-scales   
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      • Vol. 59, Issue 1, Pages: 35-42(2020) DOI: 10.13471/j.cnki.acta.snus.2020.01.005
        摘要：Key words:non-conservative system,differential variational principle of Herglotz type,adiabatic invariants,phase space  
        关键词：non-conservative system;differential variational principle of Herglotz type;adiabatic invariants;phase space   
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      • PAN Tiancheng,LV Zhongrong,WANG Li
        Vol. 59, Issue 1, Pages: 43-49(2020) DOI: 10.13471/j.cnki.acta.snus.2020.01.006
        摘要：The heat source identification problem that aims to identify the spatial locations and strengths of point heat sources and know well about the heat source properties of actual engineering structure in time belongs to the field of Inverse Heat Conduction Problem (IHCP). The heat source identification problem is generally illposed, that is, the identified results are very sensitive to the measurement noise when the measured data is insufficient. In order to overcome the ill-posedness, additional constraints need to be introduced. In this paper, a novel point heat source identification approach based on sparse regularization is proposed where the sparsity of point heat sources in space is mainly considered. Due to the existence of measurement noise, a weak enforcement of measured data through a penalty term is introduced into the objective function. Moreover, to well corporate with the sparse regularization, the alternating minimization is used to iteratively solve the separated variables of temperature and heat source, and the threshold setting method is proposed to quickly and accurately find an appropriate regularization parameter. At last, a numerical example on a twodimensional steadystate case shows that the proposed approach can quickly and accurately identified both the locations and the strengths of heat source and is insensitive to measurement noise.  
        关键词：heat source identification;sparse regularization;alternating minimization method;regularization parameter;threshold setting method   
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      • LUO Yinping,CHEN Tong,DING Hui,CHEN Jincai,LIU Yonghong,QU Xinming
        Vol. 59, Issue 1, Pages: 50-63(2020) DOI: 10.13471/j.cnki.acta.snus.2020.01.007
        摘要：Based on hourly observation data ofPM2.5andNO2concentrations at Beijing traffic stations during the Spring Festival from 2014 to 2018, the effects of vehicle emission reduction and fireworks forbidden and the impacts of emissions from fireworks and meteorological conditions on air quality were analyzed by comparing concentration characteristics and ratio ofPM2.5to CO The results showed that characteristics ofPM2.5andNO2concentrations were different during the Spring Festival. The averagePM2.5concentrations from 2014-2018 were 103.6 μg/m3and 25.3% higher than those before and after the Spring Festival. Significantly affected by vehicle emission reduction at traffic stations, theNO2concentration was 53.8 μg/m3and 19.5% lower than those before and after the Spring Festival. The concentrations ofPM2.5during the Spring Festival was lowest in 2014, and decreased year by year from 2015-2018. The burning of fireworks had relatively greater impacts onPM2.5thanNO2During the New Years Eve, the maximum contribution of hourlyPM2.5concentration from burning fireworks was 283.4-704.1 μg/m3Compared with the average of the previous four years, the concentrations ofPM2.5decreased by 25.2% andNO2reduced by only 2.4%, which impliedPM2.5pollution was improved significantly by the measures of banning fireworks within the Fifth Ring Road in 2018. Under the meteorological conditions unfavorable to atmospheric diffusion, the maximum contribution ofPM2.5concentration during the New Year’s Eve was still 45.0% lower than that of the previous four years, indicating great reduction effect of fireworks prohibition measures. The effect of meteorological conditions on thePM2.5during the Spring Festival was more significant than those ofNO2. The meteorological condition favorable for atmospheric diffusion was the main reason for the great improvement ofPM2.5pollution in 2014.  
        关键词：Spring Festival period;traffic stations;pollutants;fireworks;meteorological condition   
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      • MA Yunlong,GAO Yihang
        Vol. 59, Issue 1, Pages: 64-72(2020) DOI: 10.13471/j.cnki.acta.snus.2020.01.008
        摘要：According to the damage and failure mode of the Reusable Launch Vehicle （RLV）cryogenic tank insulation structure, combined with the NDT technology of adiabatic structure debonding，a technical solution of insulating structure debonding detection and monitoring was proposed based on ultrasonic guided waves. Also the adiabatic structure debonding (specimen stage) was detected in the temperature-load combined loading test, while the feasibility of the system was preliminarily measured by principle verification test, which provided support to the design, performance assessment and maintenance of RLV cryogenic tank insulation structure.  
        关键词：adiabatic structure;ultrasonic guided waves;damage detection;temperature-load combined test   
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      • Vol. 59, Issue 1, Pages: 71-76(2020) DOI: 10.13471/j.cnki.acta.snus.2020.01.009
        摘要：Porous materials are usually used for acoustic absorption applications.Different kinds of pore size and pore shapes were prepared by 3D printing. And the sound absorption properties of them are evaluated by both the numerical calculation using the Comsol Multiphysics software and the experimental measurement as well. It is found that the sound absorption coefficient increases with increasing the title angle of the conical holes, then reaches the maximum value when the pore angle is 45°. A further increase in the title angle of the conical holes lowers the sound absorption coefficient.  Meanwhile, the sound absorption coefficient increases gradually with increasing the pore depth from 2mm to 5mm. However, when the depth of the pores increases from 5mm to 7mm, the sound absorption coefficient doesn't have obvious change anymore.  
        关键词：porous material;3D print;pores shapes;pores size;acoustic absorption coefficient   
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      • CAO Xiaoshu,LUO Yi
        Vol. 59, Issue 1, Pages: 77-85(2020) DOI: 10.13471/j.cnki.acta.snus.2020.01.010
        摘要：Bikeshare is a green, healthy and flexible mode of transportation. While it benefits local residents, it causes some problems such as resource waste and allocation mismatch. Much research focused on the interaction between built environment and bikeshare in cities, but few studies explore the relationship between built environment and bikeshare allocation at a large scale. In this paper, the relationship between built environment and bikeshare allocation in the mainland of China and how the spatial heterogeneity of bikeshare allocation was affected by built environment variables were studied by using multiple regression analysis and with the Geographically Weighted Regression model, respectively. The results show that: 1) Built environment and bikeshare allocation are correlated. The number of retail salespersons and road density are positively related with bikeshare allocation, while income level and urban area are negatively associated with bikeshare allocation. 2) Bikeshare allocation shows a significant spatial heterogeneity. The number of retail salespersons, road density and income level increasingly affect bikeshare allocation from east to west. The urban area has a negative effect on bikeshare allocation within most cities, and its impact decreases gradually from core to periphery.  
        关键词：built environment;bikeshare allocation;geographic weighted regression   
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      • XIE Linhuan,JIANG Tao,CAO Yingjie,LI Kun,TANG Changyuan
        Vol. 59, Issue 1, Pages: 86-95(2020) DOI: 10.13471/j.cnki.acta.snus.2020.01.011
        摘要：Atmospheric precipitation is the main input source of the water cycle system, and the stable isotope compositions (δDδ18O) are greatly influenced by regional meteorological and geographical factors and are very sensitive to environmental changes. Stable oxygen and hydrogen isotope technique is widely used to study the characteristics of the global and local water circulation. The Dongjiang River Basin is located in the Pearl River Delta, China. The monsoon circulation controls the time and space distributions of precipitation by affecting the distribution of water vapor transport field. The lower reaches of the Dongjiang River was taken as the research object to study the mechanism of regional precipitation. Daily precipitation samples were collected in 2017, δD andδ18Owere measured and the relationships between δDδ18Oand temperature, precipitation were analyzed. The HYSPLIT backward trajectory model was used to trace water vapor sources and the transport of regional precipitation. The results show that the δD andδ18Ovalues ranged from -105.10‰ to +9.98‰ and -14.80‰ to -0.55‰, respectively, and the annual weighted mean values were -57.88‰ and -8.61‰. Regional Meteoric Water Line was δD=8.60δ18O+16.51(R2=0.99). The maximumδ18Oappeared in January, which was -3.47‰, and the minimum value appeared in August, which was -10.17‰. In the monthly scaleδ18Oshows “anti-temperature effect” and “quantity effect” The δD andδ18Oin precipitation which caused by water vapor in the Pacific Ocean were higher than those in the Indian Ocean. However, the δD andδ18Oin precipitation caused by the air masses from the South China Sea changed with the seasons, which weres significantly lower in summer and autumn than those in spring. There was obvious circulation effect of isotope in atmospheric precipitation.  
        关键词：hydrogen and oxygen isotopes;atmospheric precipitation;water vapor source;HYSPLIT;Dongjiang River   
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      • LI Miao,HU Mengmeng,XIA Beicheng
        Vol. 59, Issue 1, Pages: 96-104(2020) DOI: 10.13471/j.cnki.acta.snus.2020.01.012
        摘要：The Pearl River Delta (PRD) urban agglomeration is an important part of the Guangdong-Hong Kong-Macao Greater Bay. It is of great significance to study the ecological security and spatial pattern of the PRD urban agglomeration under the background of the national policy of implementing the construction of the Guangdong-Hong Kong-Macao Greater Bay. The ecological security evaluation system of urban agglomeration was constructed in the PRD based on the PSR conceptual model, and the set pair analysis and spatial autocorrelation analysis methods were applied to analyze the spatial heterogeneity and aggregation characteristics of urban agglomeration ecological security. The results show that the PRD is affected by urbanization, and the ecological security level shows an obvious spatial differentiation. The ecological security level of the central area, where it highly urbanized, is significantly lower than that of the peripheral area. The peripheral area forms an ecological barrier to the central area. The level of ecological security has a significant relationship with regional economic development, and the level of ecological security and economic development are negatively correlated in space. The clustering of ecological security in cities shows a “low-high” or “high-low” agglomeration situation. Cities with higher ecological security tend to be adjacent to cities with lower ecological security, showing a complementary spatial pattern. This spatial differentiation and aggregation characteristics have important guiding significance for the future ecological planning, urban ecological construction and ecological management of the urban agglomerations of the PRD and Guangdong-Hong Kong-Macao Greater Bay.  
          
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        发布时间：2023-12-12
      • MU Fengyun,YANG Meng,LIN Xiaosong,LONG Qiuyue,LI Mengmei,HE Yong
        Vol. 59, Issue 1, Pages: 105-113(2020) DOI: 10.13471/j.cnki.acta.snus.2020.01.013
        摘要：Kmeans model and ARMA model was applied to classify 12 369 runoff river reaches in Wushan County, and study the change of hydrological parameters in time series, and probes into the evolution of rainfall runoff process by using the machine learning algorithm RF model. Combined with the GIS spatial visualization technology and the geographical environment of the study are, the flood disaster scope is predicted and the spatial distribution of flood disasters is analyzed based on the RF model. The results show that: 1) The RF model can effectively predict the importance of parameters in the rainfallrunoff process. When the rainfall intensities are 125 mm and 150-175 mm, the change rate of water level and velocity is the largest; when the rainfall intensity is 100-175 mm, the change rate of velocity is the most intense. 2) The ARMA model is used to predict the river gradient, flow and other hydrological parameters with the best regression. Among the predicted parameters of lower level rivers, the change rate of water level and flow velocity is the most obvious, and the flow quantity has no obvious change. Compared with the change rate of water level, the change rate of flow rate is more intense, and the change rate of flow rate and water level is mainly concentrated in the river with higher grade. 3) The machine learning algorithm can effectively predict the flood prone degree in the study area. When characterizing the hydrological parameters of the study area, the change of water level is mainly concentrated in the northwest and the south central part, and the change rate of water level in the northeast and the south central part is significant. It is predicted that the water level in some areas can rise to 20 m in extremely dangerous condition.  
        关键词：machine learning;RF;K-means;ARMA;rainfall runoff;flood disaster   
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      • Vol. 59, Issue 1, Pages: 114-124(2020) DOI: 10.13471/j.cnki.jsysusse.2020.01.014
        摘要：To identify the genuine species of Hirudo (Whitmania pigraHirudo nipponica), DNA molecular method was established. Based on mitochondrial cytochromecoxidase subunit Ⅰ(COⅠ) gene, speciesspecific primers were designed forW. pigraandH. nipponicarespectively. Using three species-specific primers, PCR amplification was performed for the genuine species and the common adulterantPoecilobdella manillensisLesson, as well as the Naoxintong capsules. Results showed that both primers WF1R2 and WF2R2 could specifically amplify the DNA ofW. pigrawith amplicons of around 200 bp, while the primers HF1R2 could specifically amplify the DNA ofH. nipponicato generate amplicons of 142 bp. Besides, no amplification was obtained in the adulterantP. manillensiswith above three pairs of primers. In addition, amplicons around 200 bp were obtained in Naoxintong capsules using primers WF1R2 or WF2R2, with the same sequences asW. pigrawhich is the genuine species that the company used. These results indicated that without sequencing, the primers WF1R2 (or WF2R2) and HF1R2 could specifically amplifyW. pigraandH. nipponica, respectively. Furthermore, the primers WF1R2 and WF2R2 could be applied to identify the genuine species in Naoxintong capsule. This DNA molecular identification method is simple, accurate, with high specificity and sensitivity, thus it could be used as a supplement to the conventional method for origin identification and further improve the quality control of Hirudo and the Hirudo in Naoxintong capsule  
        关键词：Hirudo;Naoxintong Capsule;origin identification;DNA molecular identification;COⅠ gene   
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      • ZHANG Xiuxiu,YU Yanqin,TIAN Wei,ZHANG Ting,WANG Chanjuan,SHAN Keren,HE Yan
        Vol. 59, Issue 1, Pages: 125-132(2020) DOI: 10.13471/j.cnki.jsysusse.2020.01.015
        摘要：The study aimed to determine single nucleotide polymorphism of 21Y-chromosomal loci in seven ethnic minorities, including Shui, Bouyei, Dong, Gelo, Zhuang, Maonan and Mulam, of Zhuang-Dong language in the Guizhou province of China, and explore differences in the polymorphism from other Language ethnics. The SNapShot method was used to detect the complex amplicons of the 21 Y-SNPs loci in 445 males from seven Guizhou Zhuang-Dong language ethnics. Frequencies of alleles, haplotypes, and haploid populations were calculated using a direct counting method. SPSS 24 was used for principal component analyses. The haplotype diversity values were 0.597 7, 0.945 6, 0.885 6, 0.886 9, 0.768 6, 0.358 7 and 0.707 8, respectively, in the seven ethnics. We performed principal component analyses based on the frequencies of haplogroups by comparing our data with those reported for other nine ethnic groups in China. The results showed that Zhuang-Dong Language and Hmong-Mien Language were clustered together. From the perspective of patrilineal genetics, the relationship of ZhuangDong Language to Hmong-Mien Language is relatively closer than those of other ethnics.  
        关键词：Zhuang-Dong Language;Y-chromosome;SNP;genetic polymorphism;Guizhou province   
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      • ZHENG Yinglin,TONG Yichen,SUN Yingying,PANG Jiyan
        Vol. 59, Issue 1, Pages: 133-143(2020) DOI: 10.13471/j.cnki.jsysusse.2020.01.016
        摘要：Seventeen compounds (1-17) were isolated from the marine fungusAspergillus sp. Their structures were determined by nuclear magnetic resonance (NMR) spectroscopy and mass spectrum (MS). Among them, compound 1 was first found as a naturally occurring compound and the known compounds2-17were confirmed via spectrum and literatures. The bioactivities of selected compounds were preliminarily evaluated. The compound 2 exhibited moderate inhibitory activities toward three cancer cells, RPMI8226, OCI-MY5, and MCF-7 cells, and compound10had significant protective effects on prolonging the survival life ofC. elegansunder heat stress. In addition, the compound9and16showed slight inhibition effects againstStreptococcus pyogenesand meanwhile the compound17possessed slightly inhibitory activity onStreptococcus pneumoniae.  
        关键词：marine fungus;natural products;cytotoxicity;neuroprotective effects;antibacterial effects   
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      • QIAO Chaoyang,YAN Hongyan,SUN Yongqing,LIU Yisi,LV Luyao,TONG Hua,WANG Zuocheng
        Vol. 59, Issue 1, Pages: 144-153(2020) DOI: 10.13471/j.cnki.jsysusse.2020.01.017
        摘要：Using the dispersion correction density functional ωB97X-D method, the MP2 method of perturbation theory and the SMD model method of selfconsistent reaction field, the title reaction of two stable conformations(Asp_1and Asp_2) of Asp was investigated. The study of reaction channel and potential energy surface showed that the chiral enantiomer transition was realized by a series of Asp transition states of Hatom abstraction of hydroxyl ion(water clusters) and α-carbon, as well as the rotation of αcarboxy hydroxyl, β-carboxy hydroxyl, β-carboxyl and R-group. The intrinsic energy barrier of the rate-determining step of optical isomerization ofAsp_1andAsp_2induced by α-H abstraction of hydroxyl ion and H abstraction of water molecule of αcarbon was about 27.0 kJ/mol, and the corresponding intrinsic energy barriers induced by H-atom abstraction of hydroxyl ion assisted with water molecule and H-atom abstraction of two water molecule of α-carbon were about 34.0 and 40.0 kJ/mol, respectively. It could accelerate the process of Asp chiral transition that proton attacks the α-carbon of intermediate carbon anion.  
        关键词：chiral enantiomer;aspartic;hydroxyl;water molecule;density functional theory;perturbation theory;SMD model;energy barrier   
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