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	Access to hospitals: Potential vs. observed 期刊论文 OAI收割 CITIES, 2020, 卷号: 100, 页码: 12 作者: Wang, Jiaoe; Du, Fangye; Huang, Jie; Liu, Yu \| 收藏 \| 浏览/下载：21/0 \| 提交时间：2021/03/23 Observed hospital accessibility Taxi trip Catchment area Travel behavior Big data
	Access to hospitals: Potential vs. observed 期刊论文 OAI收割 CITIES, 2020, 卷号: 100, 页码: 12 作者: Wang, Jiaoe; Du, Fangye; Huang, Jie; Liu, Yu \| 收藏 \| 浏览/下载：11/0 \| 提交时间：2021/03/23 Observed hospital accessibility Taxi trip Catchment area Travel behavior Big data
	Improving Princeton Forcing Dataset over Iran Using the Delta-Ratio Method 期刊论文 OAI收割 WATER, 2020, 卷号: 12, 期号: 3, 页码: 15 作者: Zhang, Qinghuan; Tang, Qiuhong; Liu, Xingcai; Hosseini-Moghari, Seyed-Mohammad; Attarod, Pedram \| 收藏 \| 浏览/下载：28/0 \| 提交时间：2021/03/23 Iran meteorological forcing data observed data precipitation wind speed
	Improving Princeton Forcing Dataset over Iran Using the Delta-Ratio Method 期刊论文 OAI收割 WATER, 2020, 卷号: 12, 期号: 3, 页码: 15 作者: Zhang, Qinghuan; Tang, Qiuhong; Liu, Xingcai; Hosseini-Moghari, Seyed-Mohammad; Attarod, Pedram \| 收藏 \| 浏览/下载：33/0 \| 提交时间：2021/03/23 Iran meteorological forcing data observed data precipitation wind speed
	No pulsed radio emission during a bursting phase of a Galactic magnetar 期刊论文 OAI收割 Nature, 2020, 卷号: 587, 页码: 63-65 作者: HXMT \| 收藏 \| 浏览/下载：47/0 \| 提交时间：2022/02/08 Astrophysics - High Energy Astrophysical Phenomena Abstract: Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances^1-3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources^4-13, but no convincing evidence has been collected so far¹⁴. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft íray bursts¹⁵. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft íray/hard-X-ray flare^18-21. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-íray repeater (SGR) bursts were detected in íray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB-SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.
	GRB 200415A: A Short Gamma-Ray Burst from a Magnetar Giant Flare? 期刊论文 OAI收割 The Astrophysical Journal, 2020, 卷号: 899, 页码: 106 作者: HXMT \| 收藏 \| 浏览/下载：41/0 \| 提交时间：2022/02/08 Gamma-ray bursts Soft gamma-ray repeaters Magnetars Gamma-ray transient sources 629 1441 992 1853 Astrophysics - High Energy Astrophysical Phenomena Abstract: The giant flares of soft gamma-ray repeaters (SGRs) have long been proposed to contribute to at least a subsample of the observed short gamma-ray bursts (GRBs). In this paper, we perform a comprehensive analysis of the high-energy data of the recent bright short GRB 200415A, which was located close to the Sculptor galaxy. Our results suggest that a magnetar giant flare provides the most natural explanation for most observational properties of GRB 200415A, including its location, temporal and spectral features, energy, statistical correlations, and high-energy emissions. On the other hand, the compact star merger GRB model is found to have difficulty reproducing such an event in a nearby distance. Future detections and follow-up observations of similar events are essential to firmly establish the connection between SGR giant flares and a subsample of nearby short GRBs.
	In-orbit Demonstration of X-Ray Pulsar Navigation with the Insight-HXMT Satellite 期刊论文 OAI收割 The Astrophysical Journal Supplement Series, 2019, 卷号: 244, 页码: 1 作者: HXMT \| 收藏 \| 浏览/下载：15/0 \| 提交时间：2022/02/08 pulsars: general techniques: miscellaneous Astrophysics - Instrumentation and Methods for Astrophysics Abstract: In this work, we report the in-orbit demonstration of X-ray pulsar navigation with Insight-Hard X-ray Modulation Telescope (Insight-HXMT) Satellite, which was launched on 2017 June 15. The new pulsar navigation method Significance Enhancement of Pulse-profile with Orbit-dynamics is adopted to determine the orbit with observations of only one pulsar. In this test, the Crab pulsar is chosen and observed by Insight-HXMT from 2017 August 31 to September 5. Using the five-day long observation data, the orbit of Insight-HXMT is determined successfully with the three telescopes onboard: High Energy X-ray Telescope, Medium Energy X-ray Telescope, and Low Energy X-ray Telescope, respectively. By combining all the data, the position and velocity of the Insight-HXMT are pinpointed to within 10 km (3ҩ and 10 m s^-1 (3ҩ, respectively.
	Application of adaptive Kalman filter technique in initial alignment of strapdown inertial navigation system (EI CONFERENCE) 会议论文 OAI收割 29th Chinese Control Conference, CCC'10, July 29, 2010 - July 31, 2010, Beijing, China 作者: Liu P. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 In order to improve the alignment precision and convergence speed of strap-down inertial navigation system but in the active system most noise statistical characteristics are unknown an initial alignment method based on Sage-Husa adaptive filter is presented. We also derived the exactitude alignment error model and adaptive Kalman filter equation in the azimuth of small misalignment angle. As usual in this case known the noise statistical characteristics we introduce the adaptive Kalman filter. It uses the information of observed data Kalman filter is suitable on-line estimation noise statistical characteristics and state simultaneously in order to improve the filter continuously so the filter has a higher estimation accuracy than the conventional Kalman filter. By simulating verifying the adaptive Kalman filter enhances the convergence speed and alignment accuracy effectively.
	Contribution of one-photon annihilation at gamma(2S) in e(+)e(-) experiment 期刊论文 OAI收割 HIGH ENERGY PHYSICS AND NUCLEAR PHYSICS-CHINESE EDITION, 2003, 卷号: 27, 期号: 6, 页码: 465-473 作者: 王平(实); Yuan ZZ(苑长征); Mo XH(莫晓虎); Wang, P; Yuan, CZ 收藏 \| 浏览/下载：18/0 \| 提交时间：2016/06/28 observed cross section resonance one-photon annihilation branching ratio BES data taking