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Sea surface salinity-derived indexes for distinguishing two types of El Ni?o events in the tropical Pacific CNKI期刊论文 OAI收割
2021
作者: Hai ZHI; Pengfei LIN; Zhujun FANG; Hailong LIU; Rong-Hua ZHANG

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收藏 | 浏览/下载：0/0 | 提交时间：2024/12/18

Two types of El Ni?o Sea surface salinity indexes Tropical Pacific

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.

Analyzing the influences of two types of El Nino on Tropical Cyclone Genesis with a modified genesis potential index CNKI期刊论文 OAI收割
2017
作者: Wang FM(王法明); Yang YX(杨宇星); Yang L(杨磊)

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收藏 | 浏览/下载：1/0 | 提交时间：2024/12/18

two types of El Nino tropical cyclone(TC) modified genesis potential index

Analyzing the influences of two types of El Nino on Tropical Cyclone Genesis with a modified genesis potential index 期刊论文 OAI收割
CHINESE JOURNAL OF OCEANOLOGY AND LIMNOLOGY, 2017, 卷号: 35, 期号: 2, 页码: 452-465
作者: Yang Yuxing; Yang Lei; Wang Faming

收藏 | 浏览/下载：43/0 | 提交时间：2017/07/07

two types of El Nino tropical cyclone (TC) modified genesis potential index

Analyzing the influences of two types of El Nino on Tropical Cyclone Genesis with a modified genesis potential index 期刊论文 OAI收割
CHINESE JOURNAL OF OCEANOLOGY AND LIMNOLOGY, 2017, 卷号: 35, 期号: 2, 页码: 452-465
作者: Yang, YX; Yang, L; Wang, FM

收藏 | 浏览/下载：49/0 | 提交时间：2017/09/15

two types of El Nino tropical cyclone (TC) modified genesis potential index

A new method of target recognition based on rough set and support vector machine (EI CONFERENCE) 会议论文 OAI收割
2nd International Conference on Image Analysis and Signal Processing, IASP'2010, April 12, 2010 - April 14, 2010, Xiamen, China
作者: He X.

收藏 | 浏览/下载：18/0 | 提交时间：2013/03/25

Automatic target recognition (ATR) is an important task in image application. This paper concentrates on two key subroutines of ATR system: Pre-treatment and design of classifier. In the pre-treatment subroutine a new method based on Rough Set (RS) is proposed to partition the original sample set into some subsets and calculate their class membership so that some samples can be chosen by class membership to be trained. After pre-treatment an iterative algorithm based on Rough Set and Support Vector Machines (IRSSVM) is introduced to design a classifier for recognizing two types of targets. The experiment results show that IRSSVM needs less training time and the classifier is simpler and has more generalization and higher recognition rate. 2010 IEEE.

A method of aircraft image target recognition based on modified PCA features and SVM (EI CONFERENCE) 会议论文 OAI收割
9th International Conference on Electronic Measurement and Instruments, ICEMI 2009, August 16, 2009 - August 19, 2009, Beijing, China
Donghe W.; Xin H.; Wei Z.; Huilong Y.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

Automatic target recognition(ATR) is an important task in image application. This paper concentrates on two key subroutines of ATR system: Dimensionality reduction and Classifier. After pretreatment on original features a self-organizing neural network trained with the Hebbian rule is used to extract the principal component features. Then a classifier based on Directed Acyclic Graph Support Vector Machines(DAGSVM) is adopted to recognize more than two types of aircraft targets. The experiment results show the proposed method achieves better subset features and higher recognition rate. 2009 IEEE.

Rearrangeable nonblocking 88 matrix optical switches based on extended banyan network (EI CONFERENCE) 会议论文 OAI收割
作者: Zhang Y.

收藏 | 浏览/下载：27/0 | 提交时间：2013/03/25

Based on the CROSSBAR network (CN) and the BANYAN network (BN) 8 matrix optical switch two new rearrangeable nonblocking constructions of extended BANYAN network (EBN) are proposed for implementing 88 optical matrix switch. The interconnection characteristics of these two types of rearrangeable nonblocking EBN were studied optical insertion loss of 4.6 dB and the logic program for driving switching units was provided. The calculated insertion loss was 3.3 dB for 88 optical matrix switch. Silica waveguide 88 matrix optical switch was designed and fabricated according to the calculated results. The silica waveguide propagation loss of 0.1 dB/cm and waveguide-fiber coupling loss of 0.5dB/point were measured. With the fabricated 87times cross-talk of -38 dB polarization dependent loss of 0.4 dB averaged switching power of 1.6 W and switching time of 1 ms were achieved. A basic agreement between experimental results and theoretical calculated values was achieved.

Efficient excitations of radially and azimuthally polarized Nd ³⁺:YAG ceramic microchip laser by use of subwavelength multilayer concentric gratings composed of Nb2O5/SiO2 期刊论文 OAI收割
opt. express, 2008, 卷号: 16, 期号: 14, 页码: 10841, 10848
Li Jian-Lang; Ueda Ken-Ichi; Zhong Lan-Xiang; Musha Mitsuru; Shirakawa Akira; Sato Takashi

收藏 | 浏览/下载：1305/222 | 提交时间：2009/09/18

Axisymmetric Cylindrical vector beams Grating mirrors Laser diode (LD) Microchip lasers Multilayer gratings Nd:YAG ceramics Output couplers Sub wavelength Two types

Rearrangeable nonblocking 88 matrix optical switch based on silica waveguides and extended banyan network (EI CONFERENCE) 会议论文 OAI收割
Science and Technology of Dielectrics for Active and Passive Photonic Devices - 210th Electrochemical Society Meeting, October 29, 2006 - November 3, 2006, Cancun, Mexico
作者: Zhang Y.

收藏 | 浏览/下载：30/0 | 提交时间：2013/03/25

Based on the CROSSBAR network (CN) and the BANYAN network (BN) two new rearrangeable nonblocking constructions of extended BANYAN network (EBN) were proposed for implementing 88 optical matrix switch. The interconnection characteristics of these two types of rearrangeable nonblocking EBN were studied and the driver logic program of switching units was provided. The calculated insertion loss is 3.3 dB for 88 optical matrix switch. Silica waveguide 88 matrix optical switch was designed and fabricated according to the calculated results. The silica waveguide propagation loss of 0.1 dB/cm and waveguide-fiber coupling loss of 0.5dB/point were measured out. With the fabricated 88 matrix optical switch optical insertion loss of 4.6 dB cross-talk of -38 dB polarization dependent loss of 0.4 dB averaged switching power of 1.6 W and switching time of 1 ms were achieved. A basic agreement between experimental results and theoretical calculated values was achieved. copyright The Electrochemical Society.