最新刊期
卷 54 ， 期 3 ， 2015
- 摘要：Based on Biot seepage consolidation theory and wave diffraction theory, the analytical solutions to the diffracted water wave potentials and the waveinduced seepage pressures referring to porous compound vertical circular cylinder resting on permeable elastic seabed are derived by applying the eigenfunction expansion approach, and then the wave-induced lift force and overturn moment caused by the seepage pressure on the bottom of compound vertical circular cylinder are accordingly evaluated and are compared with direct diffracted wave force and moment. The results demonstrate that the porosity of the lateral surface of the circular column resting on a circular base will lead an obvious reduction in direct horizontal wave loads on compound cylinder and certain reduction in seepage overturn moment on the bottom of compound cylinder, and having slight influence on direct vertical wave loads and waveinduced seepage uplift force on compound cylinder .The variation of ocean condition and structure geometry condition may have some influence on waveinduced seepage loads, especially on seepage moment. In certain condition, wave-induced seepage loads may have same order of magnitude as the direct wave loads.关键词：porous compound circular cylinder;wave diffraction;wave force;seabed;wave-induced seepage uplift force and moment
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发布时间：2023-12-11 - 摘要：A distributed damage identification approach under moving vehicle loads is presented based on dynamic response sensitivity. Numerical studies are carried out on a simply supported beam under a vehicle with nonlinear springs for identication of distributed damage due to the crack. Combined Newmark direct integration method and Runge-kutta method are used to calculate the dynamic responses of the coupled bridge-vehicle system. The numerical results show that the distributed damage(s) can be identified accurately even with 5% noise in the measured acceleration data. And more accelerometers are needed if there are multiple cracks in the bridge.关键词：bridge-vehicle system;dynamic response;nonlinear springs;damage detection;sensitivity.
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发布时间：2023-12-11 - 摘要：To reduce the cost and difficulty of chip testing, also improve quality and yield, memory build-in self-test (MBIST) mode and scan chain test mode are included in mass-production chips. As more functions are integrated on a single chip, multiple different clocks are adopted in design. The solution presented is a physical design method named Mix-mode, which realize normalization of multi-mode based on changing the timing constraints. The method was applied in design of a video processing chip based on 130 nm process and IC Compiler (ICC) used for placement and routing. The results showed that the physical layout was better in terms of runtime, timing, power consumption, area and total wire length than that obtained from the Multi-mode method provided by ICC.关键词：multi-mode;multi-clock domain;clock domain crossing paths;physical design
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发布时间：2023-12-11 - 摘要：A method to optimize the transfer waiting time of the waterbuses is presented. The operation time and frequencies of waterbuses are assumed to be fixed, a mathematical program model is built to coordinate the arrival times of different waterbus lines at the given wharf so that the total waiting time is minimized. The genetic algorithm is proposed to solve the model. The Xidi Wharf of Guangzhou Waterbus is chosen to test the model. The result indicates that the total transfer waiting time is significantly reduced. The proposed genetic algorithm is a fast and efficient method to solve the model with acceptable error.关键词：waterbus;transfer optimization;transfer waiting time;genetic algorithm
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发布时间：2023-12-11 - 摘要：General dynamic fuzzy neural network (GD-FNN) algorithm is proposed based on the elliptic basis function (EBF). Fuzzy rules generated from the algorithm are intelligibility. It can be used as a modeling tool. and a tool of knowledge extraction. Because of a novel on-line parameter allocation mechanism for allevialing the random selection in initialization without relation to different input variable range, the proposed GD-FNN based on fuzzy ε-completeness is more easy to construct a good fuzzy system in performance.The simulation program is also developed based on the GD-FNN algorithm and ideal results are achieved by simulation in specific design case.关键词：generalized dynamic fuzzy neural network(GD-FNN);dynamic fuzzy neural network(D-FNN);radial basis function(RBF);elliptic basis function(EBF)
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发布时间：2023-12-11 - 摘要：The periodic load on the arch, in general, only causes the symmetric in-plane vibration of the arch. However, under certain conditions, it can cause in-plane anti-symmetric vibration and out-of-plane symmetric vibration with large amplitude, which is so-called the instability problem of an arch structure due to the parametric resonance. Aimed at studying the out-of-plane dynamic stability problem of circular shallow arch, the experimental work is conducted trying to explore mechanism of the out-of-plane dynamic instability under concentrated periodic load. By applying APS series vibrator, the single point harmonic excitation at vault was simulated. The B&K modal testing system was used to gain the transverse vibration response of circular arch including its vibration mode shape and damping ratio. The boundaries of unstable domain were distinguished by way of constant frequency back-and-forth sweep. The experimental results were compared with those from theory analysis, and the results show that remarkable transverse parameter resonance of the structure appears when the frequency of external excitation is about twice of the structural frequencies. The parameter resonance occurs only when the external excitation amplitude is greater than the critical excitation force.Tthe existence of the damping affects the value of the critical excitation force. The greater is the excitation, the easier does the parameter resonance phenomenon occur. The experimental work reported verifies the accuracy of calculating the outofplane dynamic instability domain of the circular shallow arch, and presents that research has reference value for the design of dynamic stability of arch structure.关键词：circular shallow arch;periodic load;parametric resonance;out-of-plane dynamic stability;vibration experiment;dynamic instability domain
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发布时间：2023-12-11 - 摘要：A mathematical model of immune cells inhibiting tumor immune evasion is studied. The model involves strongly coupled parabolic PDEs. Applying the Lptheory, Schauder-estimate and Banach Fixed Point Theorem, it is proven that the problem has an unique local solution. Then by extension method, that the local solution is global is proven.关键词：tumor growth;strongly coupled PDEs;global solution;existence and uniqueness
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发布时间：2023-12-11 - 摘要：To suppress the vibration and improve the vibration control for a flexible manipulator with the system parametric uncertainty and unknown boundary disturbance uncertainty, a robust adaptive boundary control with boundary disturbance observer is proposed by using adaptive control and boundary control technologies based on the manipulator's parameter estimation to suppress the vibration of the manipulator. With the proposed control scheme, system parameter uncertainty can be compensated and the control spillover problem can be avoided, and the boundary disturbance observer can attenuate and track the unknown boundary disturbance. The stability and uniform boundedness of the control system are both proved by Lyapunov's synthesis method. Simulation results demonstrate the effectiveness of the proposed control method to suppress the manipulator's vibration.关键词：flexible manipulator;boundary control;robust adaptive control;boundary disturbance observer
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发布时间：2023-12-11 - 摘要：A delayed SEIR epidemic model with saturation incidence rate is proposed and analyzed, and the basic reproductive number R0is defined. By analyzing the corresponding characteristic equations, the local stability of a diseasefree equilibrium P0and an endemic equilibrium P*are discussed. Further, by the comparison principle and constructing Lyapunov functions, it is found that if R0<1, the disease free equilibrium P0is globally asymptotically stable, and if R0>1, the endemic equilibrium P*is permanent.关键词：SEIR epidemic model;saturation incidence rate;time delay;basic reproductive number;global stability
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发布时间：2023-12-11 - 摘要：The problems of uniqueness concerning difference operators are studied. And some results on two general difference operators of meromorphic functions shared a value are obtained.关键词：meromorphic function;shared value;difference operators;uniqueness
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发布时间：2023-12-11 - 摘要：A highly sensitive mean-reverting stochastic differential equation is a kind of widely used financial model. A Markovian switching mechanism is added into this model, and resulting in general financial model (RS CKLS for short). The purpose is to study the Euler numerical solution of RS CKLS and apply RS CKLS to study financial issues. Firstly, it is proved that there exists a unique positive global solution for a RS CKLS under appropriate conditions. Then it is shown that the Euler numerical solution of a RS CKLS converges to its real solution in the sense of probability. Finally a RS CKLS is applied to conduct empirical analysis of 7-day Shanghai interbank offered rates. Maximum likelihood method is used to estimate model parameters, and hypothesis test results show that the RS CKLS has a better performance in fitting 7-day Shanghai interbank offered rates compared with a CKLS.关键词：Markovian switching;highly sensitive and mean-reverting stochastic process;Euler numerical solution;maximum likelihood estimation
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发布时间：2023-12-11 - 摘要：The traveling wave solutions of a competitive system with nonlocal delay are concerned. By combining fixed point theorem with generalized upper and lower solutions, the existence of traveling wave solutions is established. Then the asymptotic behavior of traveling wave solutions is obtained by the idea of contracting rectangles. Finally, the nonexistence of traveling wave solutions is proved by the theory of asymptotic spreading.关键词：contracting rectangle;asymptotic spreading;invasion and coexistence
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发布时间：2023-12-11 - 摘要：The qualitative and quantitative determination of gases released from SF6 electrical equipments plays an important role in diagnosing the failure of SF6 electric equipments. In this work, 17 gases were determined based on a dualchannel gas chromatography (GC) equipped with a helium ionization detector in GIS (Gas Insulated Switchgear), including CO, CF4CH4CO2C2F6C2H2COS, C2H4C2H8H2S, SO2F2C3F8C3H6C3H8CS2SO2and S2OF10. Gases were transported into channel A and channel B of the instrument. Channel A was composed of a 05 nm column and a Poropak Q column while channel B was made up of HP-5 capillary chromatographic column. As a result, target compounds could be separated completely. Moreover, the limit of detection (LOD) of these gases was approximate 10-8and the relative standard deviation (RSD) was less than 7%. Therefore, the proposed method was sensitive, precise and was finally applied to determine 15 gases in real samples from GIS. SO2and SO2F2could be detected in the GIS, which indicated the spark discharge inside the equipment.关键词：gases from SF6electrical equipments;gas chromatography (GC);pulsed discharge helium ionization detector (PDHID)
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发布时间：2023-12-11 - 摘要：Eight compounds 1-8 were obtained from the fermentation broth and mycelium of B-2 through modern methods for isolation and purification in order to research secondary metabolites from coral-derived endophytic bacteria Pelomonas puraquae sp. nov(B-2) . Their structures were analyzed by 1H and 13-C NMR, MS and physical methods. The results indicated that they were composed of 8 compounds including cyclo(Hyp-Phe)(1), cyclo(Pro-Tyr)(2), cyclo(Phe-Gly)(3), cyclo(Phe-Ala)(4), cyclo(Ala-Tyr)(5), cyclo(Leu-Gly)(6), cyclo(Gly-Val)(7) and cyclo(Ala-Val)(8). They were all cyclodipeptides and first acquired from the coralderived endophytic bacteria Pelomonas puraquae sp. nov(B-2).关键词：coral-derived endophytic bacteria;Pelomonas puraquae sp. nov(B-2);secondary metabolites;cyclo-dipeptides;identification
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发布时间：2023-12-11 - 摘要：The chiral transition mechanism of α-alanine confined in the armchair SWBNNT (9,9)/water complex environment was studied using the method of quantum chemistry (ONIOM(B3LYP/6-311++G(3df,3pd):UFF)∥ ONIOM(B3LYP/6-31+G(d,p):UFF)) in the paper. The result indicated that, compared s-type α-Ala and intermediate INT1 in the SWBNNT(9,9)/water complex environment with monomer molecules, the bond lengths between oxygen and hydrogen, as well as carbon and hydrogen involving hydrogen transfer were all slightly increased. However, the distance between oxygen and hydrogen was significantly shorten under the same condition. It was found that there were four reaction paths in SWBNNT(9,9). Furthermore, the processes of hydrogen transfer were all realized by the way which made one or two water molecules as bridge. The maximum energy barriers of every path were always coming from transition state where hydrogen transferred from chiral carbon to carbonyl through measurement of the potential energy surfaces of chiral reaction. The minimum of maximum energy barriers was 153.8 kJ·mol-1 in the process that Amino heterogeneous firstly, then successively hydrogen transferred inside the carboxyl and hydrogen transferred from chiral carbon to carbonyl oxygen through two water molecules as bridge. Corresponding to chiral transition of α-Ala in SWBNNT(9,9) only, the minimum of maximum energy barriers was 302.7 kJ·mol-1 which obviously reduced. Moreover, corresponding to chiral transition of αAla in water environment only, the minimum of maximum energy barriers was 167.8 kJ·mol-1 that also reduced. The results showed that the SWBNNT(9,9)/water complex environment provided a preferable catalytic action for chiral transition of α-Ala.关键词：boron nitride nanotubes;α-alanine;chiral transition;ONIOM method;density functional theory;transition state
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发布时间：2023-12-11 - 摘要：Using Zn2SO4·7H2O, NaOH as raw material, high-quality Zn2SO4(OH)2·2H2O and ZnO whisker was synthesized via liquid precipitation reaction and sintering methods process. The phase，granularity, structure of crystal morphology of whiskers samples were characterized by X-ray diffraction (XRD)，scanning electron microscopy (SEM) and thermal analysis (TGDTA). The SEM result revealed that :① the whiskers formed with fine dispersive capability, ② the crystal formed with good whisker quality, ③ the surface was smooth, and ④ the particle was dispersed in uniform distribution. From the point of growth units, the growth mechanism of Zn2SO4(OH)2·2H2O whisker was investigated in this work. The growth unit of Zn2SO4(OH)2·2H2O whisker is［Zn-(OH)6］4-. The growth process of whisker was determined to be ［Zn-(OH)6］4-and HSO-4piles up towards onedimensional direction and eventually forms whiskers. After thermal decomposition, the morphology was the same, and Zn2SO4(OH)2·2H2O whiskers eventually became the ZnO whiskers.关键词：zinc oxide;model of anion coordination polyhedron growth units;whisker;growth mechanism
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发布时间：2023-12-11 - 摘要：The effect of hydroxyapatite (HA) particles with various grain sizes and dentifrice containing hydroxyapatite on aqueous cadmium adsorption was studied. Three kinds of suspensions were prepared by adding dentifrice to HA suspensions containing 3% HA with grain sizes of 20 nm, 60 nm and 12 μm with different concentrations. Cadmium ion solutions with initial concentration of 0.2 mg/L were mixed with HA suspensions and dentifrice suspensions respectively, and then were kept still for 24 h. The residual cadmium ion concentration of the supernatant was measured by inductively coupled plasma emission spectrometer, and the sorption rate of cadmium ion was calculated. The sorption rates of cadmium ion of HA particle with 3 grain sizes were above 70%, and 20 nm HA was the best.The sorption rates of cadmium ion of dentifrice containing HA were over 50% by average, and dentifrice containing 20nm HA was the highest. Pure HA and dentifrice containing HA could absorb cadmium ions. HA with size of 20 nm showed the best sorption property. The sorption property decreased by adding dentifrice.关键词：nano hydroxyapatite;dentifrice;adsorption;cadmium ion
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发布时间：2023-12-11 - 摘要：Phytoremediation uses plants to remove pollutants including heavy metals from the environment. The roots of the plant channel pollutants residing in soil or water in the environment to above-ground plant tissues for storage. Eventually, these pollutant-containing plant parts can be harvested and properly disposed. Plants thrive by photosynthesis making solar-driven in situ localized phytoremediation a very cost-effective and environmentally-friendly method to rid contaminants. Heavy metals are the undesirable products from industries such as mining and manufacturing and they are toxic to both man and animals. It has been reported that transgenic plants can be used to detoxify heavy metals like mercury, cadmium, arsenate, and selenate from the soil. However, few leadbinding proteins have been isolated from plants. Acyl-CoA-binding proteins (ACBPs) have been demonstrated to bind lead in vitro and in vivo and the potential in using ACBPs for the phytoremediation of lead in transformed plants will be discussed.关键词：Acyl-CoA-binding proteins;heavy metals;Pb-binding;phytoremediation;transgenic plants
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发布时间：2023-12-11 - 摘要：The study mainly focuses on cell transfection efficiency and cytotoxicity of a histidylated cationic copolymer in order to explore its potential as a gene carrier. A novel histidylated cationic copolymer，PEG-b-PLG-g-PEIs-HISs(GGIS),was synthesized by free radical polymerization．The chemistry structure of GGIS was confirmed by1H-NMR.Agarose gelelectrophoresis was performed to study the capacity of plasmid DNA condensation. Particle size and zeta potential were measured at various N/P ratios. Cytotoxicity of GGIS was determined by MTT assay in HEK 293T, Hela, BEL7402 and A549 cells lines .The transfection efficiency of GGIS was specifically evaluated and monitored by flow cytometry. When the N/P less than of 30. The size of the DNA/GGIS was approximately 100～200 nm and the zeta-potential was 10~30 mV.The MTT assay showed that the cytotoxicity of GGIS was obviously lower than PEI 25K. GGIS demonstrated significantly higher transfection efficiency than PEI 25K.Therefore,GGIS with high transfection efficiency and low cytotoxicity has great potential to be used as non-viral gene carriers．关键词：gene therapy;PEI;poly(β-benzyl-L-glutamate);histidine;gene delivery;gene transfection
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发布时间：2023-12-11 - 摘要：Consistency evaluation was processed between domestic clindamycin palmitate hydrochloride dispersible tables and the original oral solution. HPLC method was applied to detect related substances with acetate (A) and 5 mmol/L ammonium acetatesolutionacetonitrile (50:50) (B) as mobile phase eluting in gradient. Dissolution was conducted by stirring paddle method with w=0.4% SDS as dissolution medium, at the rotate speed of 75 r/min for quality comparison between two products.The results showed that the kinds and total contents of related substances in clindamycin palmitate hydrochloride dispersible tablets were lower than that of the original oral solution products and the dissolution rates of both products reached more than 94% in 20 minutes.关键词：clindamycin palmitate hydrochloride;related substances;dissolution
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发布时间：2023-12-11 - 摘要：Poly (lactic-co-glycolic acid) (PLGA) microspheres loaded bovine serum albumin were prepared by WOW double emulsion method. The influence of homogenization speed during primary emulsion（5 000, 10 000, 15 000 r/min） on the physicochemical properties was investigated. Encapsulation efficiency, drug loading and particle size were used to evaluate the physicochemical properties of the microspheres. The surface and internal morphology of the microspheres was investigated by scanning electron microscopy (SEM). The structure parameters were analyzed by image analysis software. Confocal laser scanning microscopy was utilized to observe protein distribution within the skeletons of the microspheres. Finally, the connectivity of the microspheres was examined by the uptake experiments. Moreover, the release behaviors and the surface and internal structural evolution were also systematically studied. When the homogenization speed increased, the number of surface and internal pores increased, pore size of internal pores decreased. Besides, higher homogenization speed may result in slower drug release and degradation of the microspheres. But it caused no significant difference in the particle size and cross-sectioned porosity. In 10 000 r/min group, the microspheres showed highest encapsulation efficiency and lowest burst release rate in the first day and lowest surface pore connectivity. While in 5 000 r/min and 15 000 r/min group, microspheres released faster, with a higher burst release. The microspheres prepared at different homogenization speed showed different surface and internal morphology, which play a significant role in 〖WTBX〗in vitro〖WTBZ〗 release behaviors.关键词：microsphere;microscopic structure;sustained-release;poly lactic acid glycolic acid;homogenization speed
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发布时间：2023-12-11 - 摘要：Wild Allium victorialis L. in Changbai mountain was collected as raw materials to study its content variation of functional components in bulbs and leaves with different picking time, and find out the best lipid-decreasing time of Allium victorialis L. boiling liquid. Ultrasonic assisted extraction of flavones, saponins and polysaccharides in Allium victorialis L. and measured contents of the three substances individually, the bulbs and leaves boiling liquid in different picking time was taken and used for the experimental mice induced by high-fat diet. In late July, the bulbs and leaves boiling liquid has obviously decreased the content of triglyceride, total cholesterol and low density lipoprotein cholesterin. However, the liquid has obviously rise the high-density lipoprotein cholesterol. And in bulbs of this picking time: the content of flavones is 4.85 mg/g, the content of saponins is 9.54 mg/g, the content of polysaccharides is 56.91 mg/g. In leaves of this picking time: the content of flavones is 9.77 mg/g, the content of saponins is 10.94 mg/g, the content of polysaccharides is 34.24 mg/g. Wild Allium victorialis L. has a good effect of lipid-decreasing.关键词：Allium victorialis L.;flavone;saponin;polysaccharide;lipid-decreasing
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发布时间：2023-12-11 - 摘要：The relationship between the quasi-biweekly oscillation(QBW: here defined as a 10~25 day oscillation) abnormity of May-June rainfall over southern China and the QBW propagation from the tropics and mid-latitudes is studied based on the composite analysis. The results indicate distinct QBW propagations in different May-June rainfall abnormal cases. The strong QBW rainfall abnormal cases in May in southern China are linked to the QBW propagations not only from the Bay of Bengal but also from the mid-latitudes of northwestern China. However, the weak QBW rainfall abnormal cases in May are just linked to the QBW propagations from the tropics. In June, the strong and weak QBW rainfall abnormal cases in southern China are influenced by the QBW propagations from the Bay of Bengal and from the mid-latitudes，respectively.关键词：quasi-biweekly oscillation;first rainy season;rainfall;southern China
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发布时间：2023-12-11 - 摘要：Ground-based remote sensing can directly get the radiation characteristics of atmospheric aerosol, which can be used in the study of aerosol particle size distribution. Atmospheric monitoring experiment was carried out on the roof of Marine Station by using ASD spectrometer and the solar radiation was measured. Based on obtained data, this paper applies Monte Carlo to randomly generate the proportions of four aerosol components which are used to approximately solve the extinction equation to retrieve aerosol particle size distribution. The result shows that during the period of experiment the aerosol type of Yongxing Island is similar to the marine aerosol defined by the standard radiative atmosphere; the volume size distribution is bimodal distribution with the peaks at 0.01~0.1 and 1~10 μm respectively; the number concentration distribution is unimodal distribution with the peak at 0.001~0.01μm; the change rule of aerosol number concentration and volume concentration is relevant to both the movement of sea water and the deposition of aerosol particle; the correlation coefficients for number concentration and turbidity index, volume concentration and turbidity index are above 98%, which means that number and volume concentrations can be used to represent the atmospheric turbidity.关键词：maritime aerosol;Monte Carlo method;particle size distribution;Yongxing Island
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发布时间：2023-12-11 - 摘要：In order to solve the problem that logging curve identifying complex reservoir lithology has multiplicity and uncertainty, this paper uses logs to build principal component variables and takes the principal components with the cumulative variance greater than 85% as input information, ensuring that input variables are minimum and information loss is minimal. and then simplifies the data structure to identify lithology. Based on measured values of gamma ray (GR), deep resistivity (RES_BD), resistivity (RES_BM), shallow resistivity (RES_BS), neutron porosity (TNPH), bulk density (RHOB) and interval transit time (DTCO) in deep-water reservoir of the Qiongdongnan Basin, seven integrated variables were constructed. Principal component 1 and principal component 2, with the total explained variance of 85.11%, can effectively explain the comprehensive information of seven variables. Based on lithologic data obtained from sidewall core, siltstone, mudstone,and fine sandstone can be identified on the cross plot of principal component 1 and principal component 2. Additionally, the multi-fractal method was used to analyze the spectral function curves. The sandstone corresponds to spectral function curve leaning right and mudstone corresponds to spectral function curves leaning left, which can be used as valid evidence to distinguish sandstone and mudstone.关键词：southeast Qiong basin;deep-water area;lithology identification;principal component;multifractal;spectral function
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发布时间：2023-12-11 - 摘要：Hydrological processes of the Poyang Lake are significantly altered under the influences of human activities and climate changes. Ecological system has aological alterations indapted to the hydrological conditions before hydrological alterations in the Poyang Lake. Given this, we use various kinds of alterations diagnosis methods to test the lake water level. Then we use variable bandwidth kernel density estimation to fit respectively daily water level for each month before hydrological variations. We regard largest probability of water level as the ecological-level the Poyang Lake. The following results were obtained: ① The variation of water level in the Poyang Lake occured in 1979, with the increase of 0.5 meter in the mean water level. ② Variable bandwidth kernel density estimation is the best statistical method for studying of maximize density water level before hydrological alterations in the Poyang Lake. ③ After the hydrological variation, the fill rate of ecological-level reduced significantly. with an average value of ecological-level fill rate less than 50%. Runoff changes are the major factors influencing the ecological-level fill rate; Water conservancy projects and forest coverage can help to improve the low-flow, so the ecological-level fill would increased significantly in dry seasons after alterations. This research results will provide important scientific basis for the ecological conservation, water ecology and water management within in the Poyang Lake basin in a changing environment.关键词：ecological-level;hydrological alterations;kernel density estimation;variable bandwidth;Poyang Lake
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发布时间：2023-12-11 - 摘要：By using five different kinds of land surface parameterization schemes (SLAB, Noah, RUC, PleimXiu and SSiB) in WRF model and combining with the latest land cover data Globcover2009, the tests about boundary layer structural features were simulated in the Pearl River delta region from 28 to 29 April 2014. Meteorological parameters, including weed speed at 10m, temperature at 2 m, vertical profile of wind speed and temperature, were evaluated and compared to the observations from 18 surface weather stations and 1 sounding station in the research area. The results show that: ①compared with the USGS land use data, distribution of land use classes in Globcover2009 is more consistent with the current actual type of surface. The simulation precision of wind speed and temperature near the surface can be effectively improved by updating the land use data; ②WRF model can simulate the diurnal variations of surface meteorological parameters basically. Due to the lowly coastal terrain, the simulations of wind speed at 10m are more easily overestimated from these five schemes, while the results of temperature at 2m are underestimated to various degrees. Among them, the simulation result of wind speed in SLAB scheme is the best and the simulated temperature in Noah scheme is more accurate than others, the error between simulations and observations in SSiB scheme is the biggest. ③The vertical profiles of wind speed and temperature obtained by Noah, SLAB, RUC and PleimXiu are almost the same in variation trend and these simulations are in line with the actual situation. The characteristics of atmospheric boundary layer from SSiB scheme are not obvious for the reason that vertical stratification near the ground is set too sparsely.关键词：WRF model;land surface parameterization scheme;atmospheric boundary layer;Globcover2009;the Pearl River delta region
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发布时间：2023-12-11
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