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EFFECTS OF IRRIGATION METHODS AND SCHEDULING ON WATER AND ONION PRODUCTIVITY IN SEMI-ARID AREAS OF ETHIOPIA 期刊论文  OAI收割
APPLIED ENGINEERING IN AGRICULTURE, 2023, 卷号: 39, 期号: 3, 页码: 291-301
作者:  
Gebremicael, Tesfay Gebretsadkan;  Haile, Gebremedhin Gebremeskel;  Kifle, Mulubrhan;  Gebremedhin, Teferi;  Deitch, Matthew J.
  |  收藏  |  浏览/下载:5/0  |  提交时间:2023/10/09
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
  |  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.
  
A Heuristic Method for Certifying Isolated Zeros of Polynomial Systems 期刊论文  OAI收割
MATHEMATICS, 2018, 卷号: 6, 期号: 9, 页码: 18
作者:  
Dou, Xiaojie;  Cheng, Jin-San
  |  收藏  |  浏览/下载:24/0  |  提交时间:2019/01/11
Detecting drug-induced changes in ECG parameters using jacketed telemetry: Effect of different data reduction techniques 期刊论文  OAI收割
JOURNAL OF PHARMACOLOGICAL AND TOXICOLOGICAL METHODS, 2017, 卷号: 85, 页码: 38-48
作者:  
Skinner, Matthew;  Xing, Guozhen;  Lu, Jing;  Ren, Jin;  Oldman, Karen
  |  收藏  |  浏览/下载:50/0  |  提交时间:2019/01/08
Effects of group housing on ECG assessment in conscious cynomolgus monkeys 期刊论文  OAI收割
JOURNAL OF PHARMACOLOGICAL AND TOXICOLOGICAL METHODS, 2015, 卷号: 75, 页码: 44-51
作者:  
Xing, Guozhen;  Lu, Jing;  Hu, Miaomiao;  Wang, Shaodong;  Zhao, Li
  |  收藏  |  浏览/下载:36/0  |  提交时间:2019/01/08
Structure buckling load interval analysis of supercavitating projectile (EI CONFERENCE) 会议论文  OAI收割
2011 9th International Conference on Reliability, Maintainability and Safety: Safety First, Reliability Primary, ICRMS'2011, June 12, 2011 - June 15, 2011, Guiyang, China
作者:  
Zhou L.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
As a result of supercavitating projectiles with high underwater velocity  their structures undergo high longitudinal force. It is necessary to perform structure buckling load interval analysis because the uncertainty of structural own parameters should be considered. Critical buckling load of supercavitating projectiles is calculated by Galerkin method. The partial matrixes of critical buckling load implicit function to each uncertainty variable are deduced  and the interval of structure critical buckling load is calculated by interval analysis and convex model methods. Numerical results show that the nominal value  lower and upper bounds of critical buckling load increase with the increment of the ratio of base diameter to cavitator diameter. And the uncertainty degree of basic variables should be controlled as far as possible in the project for high reliability. 2011 IEEE.  
A baseline-free procedure for transformation models under interval censorship 期刊论文  OAI收割
LIFETIME DATA ANALYSIS, 2005, 卷号: 11, 期号: 4, 页码: 473-488
作者:  
Gu, MG;  Sun, LQ;  Zuo, GX
  |  收藏  |  浏览/下载:22/0  |  提交时间:2018/07/30