Wetland landscape patterns are the result of various ecological and hydrological processes. Based on land use types from 1980 to 2017, a transfer matrix, pattern analysis index, principal component were used analyze evolution in Xiong’an New Area China, which has large area with lake river wetlands. The results showed that wetland changed greatly since 2000 beach decreased greatly, while wetlands increased slightly. Beach was dominant type wetland. degree slightly decreasing trend, patches...

Abstract Sound induced by arrays of $10\times 4$ roughness elements in low-Mach-number turbulent boundary layers at ${\mathit{Re}}_{\theta } = 3065$ is studied with Lighthill’s theory and large-eddy simulation. Three fetches consisting hemispheres, cuboids short cylinders are considered. The different shapes have the same height $0. 124\delta $ , element-to-element spacing 727\delta flow blockage area. acoustically compact their images wall radiate sound primarily as acoustic dipoles plane...

As a first step toward predicting rough-wall boundary-layer noise, the sound radiated from single hemispherical roughness element and pair of elements in turbulent boundary layer atRe 7500 is investigated. The height 3.6%of thickness, or 95wall units. flowfield obtained large-eddy simulation, results are validated against experimental measurements. Acoustic calculations performed based on Curle–Powell integral solution to Lighthill equation for an acoustically compact hemisphere. radiation...

The proper orthogonal decomposition (POD) method was applied to analyzing the database obtained from direct numerical simulation (DNS) of supersonic plane mixing layers. effect different forms inner products in POD investigated. It observed that mean flow contributes a predominant part total energy, and energy spectrum turbulence fluctuations covers wide range modes. patterns leading (high energy) modes reveal structures exhibit spanwise counter rotating rolls, as well oblique vortices....

The cold regions of China (CRC) are important and vulnerable freshwater recharge areas on land, any changes in them related to the survival millions people East Asia. However, for nearly half a century, regions, extreme temperature response global warming is still poorly understood. In this study, we systematically studied since 1961 discussed possible circulation factors detail. results showed that 1) magnitudes nights warm greater than those days days, decreases increases appeared almost...

As a first step toward predicting rough-wall boundary layer noise, the sound radiation from single hemispherical roughness element and pair of elements in turbulent at Re� = 7500 is investigated. The height 3.6% thickness, or 95 wall units. flow field simulated with large-eddy simulation, results are validated against experimental measurements. Acoustic calculations performed based on Curle-Powell integral solution to Lighthill’s equation for an acoustically compact hemisphere. dominated by...

Roughness noise generation mechanisms are investigated using data from large-eddy simulations of turbulent boundary layers at Re� = 3065 over arrays 10 × 4 roughness elements. Three types elements, including hemispheres, short cylinders and cuboids considered, which share the same height 0.124�, element-to-element spacing 0.727� flow blockage area. The streamwise dipole sound spectra a common peak fh/U∞ 0.17. surface pressure in fetch elevated all frequencies have smaller correlation length...

Abstract Currently, the weakened connectivity of wetland ecosystems is most important factor leading to destruction, degradation, and disappearance wetlands. Studying changes in enables understanding hydrological processes provides significant support for study ecological water demand. However, recent research on has primarily focused intuitive Heilongjiang River Basin China (HRBC) terms hydrology geomorphology, while impact habitats been ignored. The present applied an innovative method...

The sound radiation by turbulent boundary-layer flow over an array of 10× 4 roughness elements is studied using large-eddy simulation and Lighthill’s theory. Two types elements, hemispheres cuboids the same height, are considered. height 12.4% boundary layer thickness 17% spacing between neighboring in both directions. Reynolds number based on momentum 3065. acoustically compact their images wall radiate primarily as acoustic dipoles plane wall. characteristics found to be strongly dependent...

Abstract The water level of marsh wetlands is a dominant force controlling the wetland ecosystem function, especially for aquatic habitat. For different species, requirements vary in time and space, therefore ensuring suitable levels periods crucial maintenance biodiversity wetlands. Based on hydrodynamic modelling habitat suitability assessment, we determined dynamic considering service at two‐dimensional model was used to simulate temporal spatial variation level. target species various...

Emergency ecological water replenishment(EEWR) has become a major strategy for recovering degraded wetland ecosystems worldwide. However, the actual replenishment process mainly depended on tradeoff and experience between managers of Taoer River Xianghai Wetland, which is very random lacks theoretical guidance. Thus, there urge to assessing effect help optimize process. With contrasting results as different ecosystem elements respond differently, optimization should be based improvement...

Wetlands have powerful runoff regulation functions, which can effectively store and retain surface runoff. The function of wetlands is affected by wetland areas, affect the capacity flood control. To explore law area change main Naolihe River Basin (MWNRB), visual interpretation method was used to extract wetlands. identify reasons for changes in MWNRB, maximum likelihood method, minimum distance neural network were classify land use types from remote sensing images; M-K variation point test...

The selection of representative fishes is the first problem to be solved in ecological scheduling conducted by downstream cascade reservoir Jinsha River for protection fish species Yangtze Upstream National Nature Reserve Rare and Endemic Fishes (hereinafter referred as "the Reserve"). This paper has presented basic steps determine established evaluation index system representativeness that serves ecosystem hydrology regulation. result showed Acipenser dabryanus Myxocyprinus asiaticus could...

A computational study is carried out to predict rough-wall boundary layer noise and elucidate generation mechanisms. As a first step, the sound radiation from single hemispherical roughness element in turbulent at Reθ=7500 investigated. The height 3.6% of thickness, or 95 wall units. flow field computed by large-eddy simulation. velocity statistics show reasonable agreement with experimental data measured Virginia Tech. Acoustic calculations are performed based on Curle-Powell integral...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation Qin Yang, Yulu Liu, Haijun Zhang, Chuncheng Zuo; Derivation of generalized Maxwell velocity slip model. AIP Conf. Proc. 9 December 2014; 1628 (1): 382–387. https://doi.org/10.1063/1.4902618 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar...

This paper measures companies' credit risks and qualitatively analyzes the relationship between as well capital structures by calculating distance to default of listed companies. It draws a conclusion that corporate risk correlates closely structure ratio. The more liabilities company are, less possibility for it repay its debt will be, which mean, larger risks. Meanwhile, higher assets-liability ratio is, corresponding equity rights interests multiplier are.

In the face of status quo credit risk measurement academic research and practical in China, banks' can be divided into interior integral these two levels. Through analysis, it is found that most suitable objective conditions commercial internal method China KMV model, with strong theoretical significance.

To examine the relationship of morphological characters sagittal otolith and age Liza haematocheila in Yangtze Estuary, we analyzed parameters 324 pairs otoliths extracted from 358 L. specimens Estuary February to June 2017. The results showed that had rostrum, antirostrum obvious central notch. size shape significantly changed with their growth, regular melon seeds outline long narrow leaf increasing irregular wavy outline. average density was 1.52 mg·mm-2. rectangularity 0.68. length...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation Qin Yang, Haijun Zhang, Yulu Liu; Assessment of a modified slip boundary condition the Navier-Stokes equation for oscillatory Couette flows. AIP Conf. Proc. 9 December 2014; 1628 (1): 765–769. https://doi.org/10.1063/1.4902670 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley...