中国科学院机构知识库网格系统: 检索

Individual Discriminative Ability of Resting Functional Brain Connectivity is Susceptible to the Time Span of MRI Scans 期刊论文 OAI收割
NEUROSCIENCE, 2022, 卷号: 482, 页码: 43-52
作者: Ni, Huangjing; Song, Ming; Qin, Jiaolong; Jiang, Tianzi

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收藏 | 浏览/下载：24/0 | 提交时间：2022/06/10

individual identification brain connection individual differences imaging time span

Improving speech enhancement by focusing on smaller values using relative loss 期刊论文 OAI收割
IET SIGNAL PROCESSING, 2020, 卷号: 14, 期号: 6, 页码: 374-384
作者: Li, Hongfeng; Xu, Yanyan; Ke, Dengfeng; Su, Kaile

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收藏 | 浏览/下载：25/0 | 提交时间：2020/09/07

speech enhancement speech intelligibility performance evaluation learning (artificial intelligence) neural nets absolute differences speech quality relative loss single-channel speech enhancement noisy speech ideal ratio mask phase-sensitive mask mean square error loss function absolute error values magnitude spectra deep learning clean speech recovery short-time objective intelligibility signal-to-distortion ratio segmental signal-to-noise ratio performance evaluation

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：59/0 | 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.

An analysis of first-time and repeat visitors to Korean national parks from 2007 and 2013 期刊论文 OAI收割
Journal of Mountain Science, 2017, 卷号: 14, 期号: 12, 页码: 2527-2539
作者: Yunseon CHOE; Michael A. SCHUETT; Kyu-Won SIM

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收藏 | 浏览/下载：140/0 | 提交时间：2017/12/07

ThIs Paper ExamIned VIsiTors To Bukhansan NatiOnal Park In Korea Based On First-time And Repeat vIsitatiOn. Bukhansan NatiOnal Park Is Korea's Most Heavily vIsited NatiOnal Park With Annual vIsitatiOn Of Six milliOn VIsiTors In 2015. Data Used In ThIs Article Were Collected On-site In The Park In 2007 And 2013 By The Korea NatiOnal Park Service (Knps). The Study Variables Included Socio-demographics Travel Behavior Motivation And Satisfaction With Park Attributes Services And Facilities. Data Were Analyzed By Each Study Year For First-time And Repeat Visitors. Results Showed Significant Differences For Both First-time And Repeat Visitors.On Several Socio-demographic Travel Behavior And Motivation Variables Within Each Study Year. For Satisfaction With Park Attributes Facilities And Services First-time VisiTors Were Significantly Different From Repeat VisiTors On Seven Variables For Both Years. implicatiOns Are Given Regarding Programs And Services To Improve visiTor satisfactiOn And Sustain The Natural Cultural And HisTorical Resources At Bukhansan nAtional Park And Other nAtional Parks In Korea. Future Research Suggestions Are Provided To Learn More About visiTor Characteristics StAndards Of Quality And Preferences In The National Parks.

Time series decomposition of remotely sensed land surface temperature and investigation of trends and seasonal variations in surface urban heat islands SCI/SSCI论文 OAI收割
2016
作者: Quan J. L.; Zhan, W. F.; Chen, Y. H.; Wang, M. J.; Wang, J. F.

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收藏 | 浏览/下载：26/0 | 提交时间：2017/11/09

remote sensing land surface temperature urban heat island time series decomposition temporal variation climatology split-window algorithm satellite data energy-balance orbital drift humidity differences rural humidity vapor-pressure annual cycle emissivity climate

Chinese and Australians showed difference in mental time travel in emotion and content but not specificity 期刊论文 OAI收割
FRONTIERS IN PSYCHOLOGY, 2015, 卷号: 6, 期号: 0, 页码: 879
作者: Chen, Xing-Jie; Liu, Lu-Lu; Cui, Ji-Fang; Wang, Ya; Shum, David H. K.

收藏 | 浏览/下载：34/0 | 提交时间：2015/09/08

cultural differences future thinking mental time travel autobiographical memory Chinese Australian

Multiple-port inp/ingaasp square-resonator microlasers 期刊论文 iSwitch采集
Ieee journal of selected topics in quantum electronics, 2011, 卷号: 17, 期号: 6, 页码: 1656-1661
作者: Che, Kai-Jun; Yao, Qi-Feng; Huang, Yong-Zhen; Cai, Zhi-Ping; Yang, Yue-De

收藏 | 浏览/下载：40/0 | 提交时间：2019/05/12

Finite-differences time-domain (fdtd) Inp/ingaasp Metallically confined Multiple-port Square-resonator microlasers

Dynamic optimization of valveless micropump (EI CONFERENCE) 会议论文 OAI收割
2011 16th International Solid-State Sensors, Actuators and Microsystems Conference, TRANSDUCERS'11, June 5, 2011 - June 9, 2011, Beijing, China
Deng Y. B.; Wu Y. H.; Xuan M.; Korvink J. G.; Liu Z. Y.

收藏 | 浏览/下载：20/0 | 提交时间：2013/03/25

For the first time this paper reports on an effective topology optimization method to improve the output net flux for valveless micropumps. The micropump considered here is actuated by the vibration of membranes and can generate a net flow along the optimized rigid fluidic channel. The detailed layout of the micropump channel is optimized with respect to a number of factors which influence the output net flux of liquid such as the number of actuation elements the positions of actuation elements the driving phase differences and the driving frequency. Accordingly the layouts of several novel valveless micropumps are presented. 2011 IEEE.

Simulation and experiment of the static FTIR based on micro multi-step mirrors (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Sensor and Micromachined Optical Device Technologies, May 24, 2011 - May 26, 2011, Beijing, China
作者: Liang Z.-Z.; Zhang J.; Zhang J.; Zhang J.; Zhu W.-B.

收藏 | 浏览/下载：30/0 | 提交时间：2013/03/25

In recent years Fourier transform spectrometer (FTS) with small size and low mass is required in many applications with growing need for real-time and small platform spectral detection. In this paper a micro Fourier transform infrared spectrometer (FTIR) based on spatial modulation mode was designed. This spectrometer has the advantages of high stability and simplified configuration. It also promises optical path differences (OPD) with high precision as MOEMS technology is used in manufacturing the key components. The simulation and the experiments with regard to this FTIR configuration have been done. Firstly the diffraction effect of the micro multi-step mirrors (MMSMs) is studied. We discuss the influence to the reversed spectrum by different mirror widths and different diffraction distances. Secondly we simulate and analyze the influence of the source solid angle to the spectral resolution. Thirdly we set up the theoretical model of the collimation error which is mainly from the defocus of the optical system and analyze the result caused by the collimation error. Fourthly a new discrete Fourier transform arithmetic using least-squares cosines progression (LSCP) is proposed which can reconstruct the spectrum with nonuniform sampled signals. Finally the MMSMs are fabricated used the MOEMS technology and the structural parameters are tested. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

Experimental investigation on the J-pipe in offshore oilfield 会议论文 OAI收割
21st International Offshore and Polar Engineering Conference, ISOPE-2011, Maui, HI, United states, JUN 19-24, 2011
作者: Li ZY(李中阳); Lin M(林缅); Li ZY(李中阳)

收藏 | 浏览/下载：18/0 | 提交时间：2013/02/26

Dynamic response Fiber Bragg gratings Flow fields Offshore oil fields Velocity measurement Vibrations (mechanical) Vortex flow Vortex shedding Dynamic strain Experimental investigations J-pipe Particle image velocimetries Straight pipe Time-differences Vortex induced vibration