中国科学院机构知识库网格系统: 检索

Climate-Vegetation Coverage Interactions in the Hengduan Mountains Area, Southeastern Tibetan Plateau, and Their Downstream Effects 期刊论文 OAI收割
ADVANCES IN ATMOSPHERIC SCIENCES, 2024, 页码: 16
作者: Fang, Congxi; Chen, Jinlei; Ouyang, Chaojun; Wang, Lu; Sun, Changfeng

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收藏 | 浏览/下载：52/0 | 提交时间：2024/03/25

Hengduan Mountains Area normalized difference vegetation index climate change net heat flux downstream effects

An underlying clock in the extreme flip-flop state transitions of the black hole transient Swift J1658.2-4242 期刊论文 OAI收割
Astronomy and Astrophysics, 2020, 卷号: 641, 页码: A101
作者: HXMT

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收藏 | 浏览/下载：58/0 | 提交时间：2022/02/08

accretion accretion disks black hole physics X-rays: binaries time Astrophysics - High Energy Astrophysical Phenomena Abstract:
Aims: Flip-flops are top-hat-like X-ray flux variations, which have been observed in some transient accreting black hole binary systems, and feature simultaneous changes in the spectral hardness and the power density spectrum (PDS). They occur at a crucial time in the evolution of these systems, when the accretion disc emission starts to dominate over coronal emission. Flip-flops remain a poorly understood phenomenon, so we aim to thoroughly investigate them in a system featuring several such transitions.
Methods: Within the multitude of observations of Swift J1658.2-4242 during its outburst in early 2018, we detected 15 flip-flops, enabling a detailed analysis of their individual properties and the differences between them. We present observations by XMM-Newton, NuSTAR, Astrosat, Swift, Insight-HXMT, INTEGRAL, and ATCA. We analysed their light curves, searched for periodicities, computed their PDSs, and fitted their X-ray spectra, to investigate the source behaviour during flip-flop transitions and how the interval featuring flip-flops differs from the rest of the outburst.
Results: The flip-flops of Swift J1658.2-4242 are of an extreme variety, exhibiting flux differences of up to 77% within 100 s, which is much larger than what has been seen previously. We observed radical changes in the PDS simultaneous with the sharp flux variations, featuring transitions between the quasi-periodic oscillation types C and A, which have never been observed before. Changes in the PDS are delayed, but more rapid than changes in the light curve. Flip-flops occur in two intervals within the outburst, separated by about two weeks in which these phenomena were not seen. Transitions between the two flip-flop states occurred at random integer multiples of a fundamental period of 2.761 ks in the first interval and 2.61 ks in the second. Spectral analysis reveals the high and low flux flip-flop states to be very similar, but distinct from intervals lacking flip-flops. A change of the inner temperature of the accretion disc is responsible for most of the flux difference in the flip-flops. We also highlight the importance of correcting for the influence of the dust scattering halo on the X-ray spectra.

The Automatic Detection of the Continuum Problem in the Stellar Spectra Based on Distance Metric 期刊论文 OAI收割
SPECTROSCOPY AND SPECTRAL ANALYSIS, 2017, 卷号: 37, 期号: 7, 页码: 2246-2249
作者: Yu Jing-jing; Pang Jing-chang; Meng Fan-long; Wei Peng

收藏 | 浏览/下载：24/0 | 提交时间：2017/09/06

Continum problem Lick indices Template matching Subclass matching Continuum normalization Flux difference

Preventing numerical oscillations in the flux-split based finite difference method for compressible flows with discontinuities, II 期刊论文 OAI收割
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, 2016, 卷号: 80, 期号: 5, 页码: 306-316
作者: He ZW; Zhang YS; Li XL(李新亮); Tian BL

收藏 | 浏览/下载：30/0 | 提交时间：2016/03/21

contact discontinuity material interface finite difference method flux vector splitting local characteristic decomposition equation of state WENO

Preventing numerical oscillations in the flux-split based finite difference method for compressible flows with discontinuities 期刊论文 OAI收割
JOURNAL OF COMPUTATIONAL PHYSICS, 2015, 卷号: 300, 页码: 269-287
作者: He ZW; Zhang YS; Li XL(李新亮); Li L; Tian BL

收藏 | 浏览/下载：45/0 | 提交时间：2016/01/08

Compressible flows Contact discontinuity Material interface Numerical oscillations Finite difference method Flux vector splitting WENO

Quantifying the heat flux regulation of metropolitan land use/land cover components by coupling remote sensing modeling with in situ measurement SCI/SSCI论文 OAI收割
2015
作者: Kuang W. H.; Dou, Y. Y.; Zhang, C.; Chi, W. F.; Liu, A. L.

收藏 | 浏览/下载：35/0 | 提交时间：2015/12/09

urban urban heat island heat flux Bowen ratio land use land cover components surface-energy balance difference vegetation index urban surface impervious surface temperature retrieval longwave radiation thematic mapper regional-scale soil-moisture local-scale

Net ecosystem productivity of temperate grasslands in northern China: An upscaling study 期刊论文 OAI收割
AGRICULTURAL AND FOREST METEOROLOGY, 2014, 卷号: 184, 页码: 71-81
作者: Zhang, Li; Guo, Huadong; Jia, Gensuo; Wylie, Bruce; Gilmanov, Tagir

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收藏 | 浏览/下载：10/0 | 提交时间：2023/03/30

Flux tower Moderate resolution imaging spectroradiometer (MODIS) Net ecosystem production (NEP) Normalized difference vegetation index (NDVI) Piecewise regression

Evaluating one- and two-source energy balance models in estimating surface evapotranspiration from Landsat-derived surface temperature and field measurements SCI/SSCI论文 OAI收割
2013
Tang R. L.; Li Z. L.; Jia Y. Y.; Li C. R.; Chen K. S.; Sun X. M.; Lou J. Y.

收藏 | 浏览/下载：36/0 | 提交时间：2014/12/24

sensible heat-flux radiometric temperature profile relationships vegetation evaporation difference algorithm range water soil

Thermal Analysis of a New Type Langmuir Probe Based on Numerical Simulation and Experimental Studies 期刊论文 OAI收割
JOURNAL OF FUSION ENERGY, 2012, 卷号: 31, 期号: 1, 页码: 79-83
作者: Wang, Tao; Yao, Lieming; Zhou, Yong; Yan, Shengmei

收藏 | 浏览/下载：30/0 | 提交时间：2015/07/10

Heat flux Thermal state Thermal contact resistance Langmuir Probe (LP) Temperature difference

Upwind compact finite difference scheme for time-accurate solution of the incompressible Navier-Stokes equations 期刊论文 OAI收割
APPLIED MATHEMATICS AND COMPUTATION, 2010, 卷号: 215, 期号: 9, 页码: 3201-3213
作者: Shah, Abdullah; Yuan, Li; Khan, Aftab

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收藏 | 浏览/下载：31/0 | 提交时间：2018/07/30

Incompressible Navier-Stokes equation Artificial compressibility method Upwind compact finite difference Flux-difference splitting Dual-time stepping Kovasznay flow problem Oscillating plate Taylor's decaying vortices Doubly periodic shear layer