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The LISA-Taiji Network:Precision Localization of Coalescing massive Black Hole Binaries

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Research 2021年第1期2021卷 316-322页

作者： Wen-Hong Ruan Chang Liu Zong-Kuan Guo Yue-Liang Wu Rong-Gen Cai CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesP.O.Box 2735Beijing 100190China School of Physical Sciences University of Chinese Academy of SciencesNo.19A Yuquan RoadBeijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

We explore a potential LISA-Taiji network to fast and accurately localize the coalescing massive black hole *** an equalmass binary located at redshift of 1 with a total intrinsic mass of 10^(5)M_(⊙),the LISA-Taiji network may achieve almost four orders of magnitude improvement on the source localization region compared to an individual *** precision measurement of sky location from the gravitational-wave signal may completely identify the host galaxy with low redshifts prior to the final black hole *** identification of the host galaxy is vital for the follow-up variability in electromagnetic emissions of the circumbinary disc when the binary merges to a new black hole and enables the coalescing massive black hole binaries to be used as a standard siren to probe the expansion history of the Universe.

关键词： galaxy massive gravitational

massive Sulphide Deposits Related to the Volcano-Passive Continental Margin in the Altay Region

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Acta Geologica Sinica(English Edition) 1999年第3期73卷 253-263页

作者： WANG Jingbin DENG Jiniu ZHANG Jinhong QIN Kezhang Beijing Institute of Geology for Mineral Resources State Bureau of Nonferrous Metal Industry Andingmenwai Beijing 100012

The Devonian volcano-passive continental margin in southern Altay is a significant volcanogenic massive sulphide metallogenic belt. Acidic volcanism has been dominant on the inner side of the volcano-passive continental margin, i.e., near the old land, resulting in a Pb-Zn metallogenic sub-belt, in which the ore deposits are hosted by sedimentary rocks in volcanic series, as represented by the large Koktal Pb-Zn deposits. In the central part of the margin far away from the old land, bimodal volcanic formations are well developed, forming volcanics-hosted Cu-Zn metallogenic sub-belts, e.g., the large-scale Ashele Cu-Zn deposit. The Qiaoxiahala sub-belt on the outer side of the margin near the ocean ridge is located at the spreading central trough, where ophiolite suites are developed. This type of deposits is rich in gold and copper, similar to the Cyprus-type Fe-Cu-Au metallogenic sub-belt in metallogenic environment (represented by the Qiaoxiahala medium-scale Fe-Cu-Au deposit). From the old land to the ocean, the mineralizing age becomes younger, i.e., from Early Devonian→Early and Middle Devonian→Middle Devonian, forming a complete metallogenic zoning series on the volcano-passive continental margin. Comparative studies show that the massive sulphide deposits distributed on the volcano-passive continental margin are different from those formed under a plate subduction regime and oceanic ridge environment; the former have their unique features and wide distributions, representing a new type of volcanogenic massive sulphide deposits—the Altay type.

关键词： volcano-passive continental margin massive sulphide deposit Altay type Xinjiang

p-capture reaction cycles in rotating massive stars and their impact on elemental abundances in globular cluster stars: A case study of O, Na and Al

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Research in Astronomy and Astrophysics 2017年第8期17卷 31-46页

作者： Upakul Mahanta Aruna Goswami Hiralal Duorah Kalpana Duorah Department of Physics Bajali CollegePathsalaPIN 781325India Indian Institute of Astrophysics BengaluruPIN 560034India Department of Physics Gauhati UniversityGuwahatiPIN 781014India

Elemental abundance patterns of globular cluster stars can provide important clues for understanding cluster formation and early chemical *** origin of the abundance patterns,however,still remains poorly *** have studied the impact of p-capture reaction cycles on the abundances of oxygen,sodium and aluminium considering nuclear reaction cycles of carbon-nitrogenoxygen-fluorine,neon-sodium and magnesium-aluminium in massive stars in stellar conditions of temperature range 2×107to 10×107K and typical density of 102gm *** have estimated abundances of oxygen,sodium and aluminium with respect to Fe,which are then assumed to be ejected from those stars because of rotation reaching a critical *** ejected abundances of elements are then compared with their counterparts that have been observed in some metal-poor evolved stars,mainly giants and red giants,of globular clusters M3,M4,M13 and NGC *** observe an excellent agreement with[O/Fe]between the estimated and observed abundance values for globular clusters M3 and M4 with a correlation coefficient above 0.9 and a strong linear correlation for the remaining two clusters with a correlation coefficient above *** estimated[Na/Fe]is found to have a correlation coefficient above 0.7,thus implying a strong correlation for all four globular *** far as[Al/Fe]is concerned,it also shows a strong correlation between the estimated abundance and the observed abundance for globular clusters M13 and NGC 6752,since here also the correlation coefficient is above 0.7 whereas for globular cluster M4 there is a moderate correlation found with a correlation coefficient above *** sources of these discrepancies are discussed.

关键词： Galaxy globular cluster individual(M3,M4,M13,NGC 6752)—stars abundances—stars massive

Low-Complexity Channel Reconstruction Methods Based on SVD-ZF Precoding in massive 3D-MIMO Systems

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China Communications 2015年第S1期12卷 49-57页

作者： REN Yuwei SONG Yang SU Xin Beijing University of Posts and Telecommunications State Key Laboratory of Wireless Mobile Communications China Academy of Telecommunications Technology

In this paper, we study the low-complexity channel reconstruction methods for downlink precoding in massive multiple-Input multiple-Output(MIMO) systems. When the user is allocated less streams than the number of its antennas, the base station(BS) or user usually utilizes the singular value decomposition(SVD) to get the effective channels, whose dimension is equal to the number of streams. This process is called channel reconstruction and done in BS for time division duplex(TDD) mode. However, with the increasing of antennas in BS, the computation burden of SVD is getting incredible. Here, we propose a series of novel low-complexity channel reconstruction methods for downlink precoding in 3D spatial channel model. We consider different correlations between elevation and azimuth antennas, and divide the large dimensional matrix SVD into two kinds of small-size matrix SVD. The simulation results show that the proposed methods only produce less than 10% float computation than the traditional SVD zero-forcing(SVD-ZF) precoding method, while keeping nearly the same performance of 1Gbps.

关键词： channel reconstruction SVD 3D-MIMO massive MIMO

User Assisted Cooperative Relaying in Beamspace massive MIMO NOMA Based Systems for Millimeter Wave Communications

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China Communications 2019年第6期16卷 103-113页

作者： Jaipreet Kaur Maninder Lal Singh Department of Electronics Technology Guru Nanak Dev University

A novel scheme‘user assisted cooperative relaying in beamspace massive multiple input multiple output(M-MIMO)non-orthogonal multiple access(NOMA)system’has been proposed to improve coverage area,spectrum and energy efficiency for millimeter wave(mmWave)communications.A downlink system for M users,where base station(BS)is equipped with beamforming lens antenna structure having NRF radio frequency(RF)chains,has been considered.A dynamic cluster of users is formed within a beam and the intermediate users(in that cluster)between beam source and destination(user)act as relaying *** the use of successive interference cancellation(SIC)technique of NOMA within a cluster,the relaying stations relay the symbols with improved power to the *** maximizing achievable sum rate,transmit precoding and dynamic power allocation for both intra and inter beam power optimization are *** for performance evaluation are carried out to validate that the proposed system outperforms the conventional beamspace M-MIMO NOMA system for mmWave communications in terms of spectrum and energy efficiency.

关键词： cooperative relaying system(CRS) millimeter wave(mmWave) massive multiple input multiple output(M-MIMO) non-orthogonal multiple access(NOMA) power allocation sum rate

Evaluation of seismic potential in a longwall mine with massive sandstone roof under deep overburden

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International Journal of Mining Science and Technology 2018年第1期28卷 115-119页

作者： Mark A.Van Dyke Wen H.Su Joe Wickline Ground Control Branch NIOSHPittsburgh15236 PAUSA Coronado Coal LLC BeckleyWVUSA

A recent seismic event was recorded by a deep longwall mine in Virginia at 3.7 ML on the local magnitude scale and 3.4 MMS by the United States Geological Survey(USGS) in *** investigations by the National Institute for Occupational Safety and Health(NIOSH) and Coronado Coal researchers have shown that this event was associated with geological features that have also been associated with other, similar seismic events in *** mapping and geological exploration in the mining area has made it possible to forecast possible locations for future seismic *** order to use the geology as a forecaster of mining-induced seismic events and their energy potential, two primary components are *** first component is a long history of recorded seismic events with accurately plotted *** second component is a high density of geologic data within the mining *** this case, 181 events of 1.0 MLor greater were recorded by the mine's seismic network between January, 2009, and October, *** the mining area, 897 geophysical logs, 224 core holes, and 1031 fiberscope holes were examined by mine *** this information, it was found that overburden thickness, sandstone thickness, and sandstone quality contributed greatly to seismic *** the data was analyzed, a pattern became apparent indicating that the majority of seismic events occurred under specific *** forecast maps were created based on geology of previous seismic *** forecast maps have shown an accuracy of within 74%–89% when compared to the recorded 181 events that were1.0 MLor greater when considering three major geological criteria of overburden thickness of 579.12 m or greater, 6.096–12.192 m of sandstone within 15.24 m of the Pocahontas number 3 seam, and a longwall caving height of 4.572 m or less.

关键词： Seismic Mapping Deep overburden massive sandstone

massive presacral bleeding during rectal surgery: From anatomy to clinical practice

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World Journal of Gastroenterology 2013年第25期19卷 4039-4044页

作者： Zheng Lou Wei Zhang Rong-Gui Meng Chuan-Gang Fu Department of Colorectal Surgery Changhai Hospital

AIM: To investigate control of two different types of massive presacral bleeding according to the anatomy of the presacral venous system. METHODS: A retrospective review was performed in 1628 patients with middle or low rectal carcinoma who were treated surgically in the Department of Colorectal Surgery, Changhai Hospital, Shanghai, China from January 2008 to December 2012. In four of these patients, the presacral venous plexus (n = 2) or basivertebral veins (n = 2) were injured with massive presacral bleeding during mobilization of the rectum. The first two patients with low rectal carcinoma were operated upon by a junior associate professor and the source of bleeding was the presacral venous plexus. The other two patients with recurrent rectal carcinoma were both women and the source of bleeding was the basivertebral ***: Two different techniques were used to con-trol the bleeding. In the first two patients with massive bleeding from the presacral venous plexus, we used suture ligation around the venous plexus in the area with intact presacral fascia that communicated with the site of bleeding (surrounding suture ligation). In the second two patients with massive bleeding from the basivertebral veins, the pelvis was packed with gauze, which resulted in recurrent bleeding as soon as it was removed. Following this, we used electrocautery applied through one epiploic appendix pressed with a long Kelly clamp over the bleeding sacral neural foramen where was felt like a pit Electrocautery adjusted to the highest setting was then applied to the clamp to "weld" closed the bleeding point. Postoperatively, the blood loss was minimal and the drain tube was removed on days 4-7. CONCLUSION: Surrounding suture ligation and epiploic appendices welding are effective techniques for controlling massive presacral bleeding from presacral venous plexus and sacral neural foramen, respectively.

关键词： massive presacral bleeding Rectal surgery Suture ligation Welding

High-Velocity H_(2)O Masers Associated massive Star Formation Regions

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Chinese Physics Letters 2001年第12期18卷 1663-1665页

作者： XU Ye JIANG Dong-Rong ZHENG Xing-Wu GU Min-Feng YU Zhi-Yao PEI Chun-Chuan Shanghai Astronomical Observatory National Astronomical ObservatoriesChinese Academy of SciencesShanghai 200030 Department of Astronomy Nanjing UniversityNanjing 210093 Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008

We report on the results of ^(12)CO (1-0) emission associated with H2O masers and massive star formation regions to identify high-velocity H2O masers. Several masers have a large blueshift, even up to 120km·s^(-1), with respect to the CO peak, but no large redshifted maser appears. This result suggests that high-velocity H_(2)O masers can most probably occur in high mass star-forming regions and quite a number of masers stem from the amplifications of a background source, which may enable those undetectable weak masers to come to an observable level.

关键词： massive probably source

Diseases and compromised health states of massive Porites spp. in the Gulf of Thailand and the Andaman Sea

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Acta Oceanologica Sinica 2019年第1期38卷 118-127页

作者： Watchara Samsuvan Thamasak Yeemin Makamas Sutthacheep Sittiporn Pengsakun Juthamart Putthayakool Monthaphat Thummasan Department of Biology Faculty of Science Ramkhamhaeng University

In this study, we assess coral health by detecting the severity of coral diseases and compromised health states on massive Porites. Field surveys are conducted at twenty-two sites covering the eastern, inner and western Gulf of Thailand as well as the Andaman Sea during 2010–2015. A total of nine coral diseases and signs of compromised health are observed in the waters of Thailand, consisting of pigmentation responses(pink lines, pink patches,pink spots and pink borers), white syndromes(white patches, white bands and ulcerative white spots), growth anomalies, and unusual bleaching patterns. The highest severity of all observed coral diseases and signs of compromised health are found at Ko Khang Khao in the inner Gulf of Thailand, while that observed in the Andaman Sea is relatively low. Composition of the diseases vary across the study sites. Four groups of study sites,in which there is an 80% similarity of diseases or signs of compromised health composition, are clustered and detected based on the Bray-Curtis similarity. The canonical analysis of principal coordinates reveal that most study sites in the Gulf of Thailand, especially the inner Gulf of Thailand, tend to show a high severity of the diseases. The association of disease severity and composition and the level of human impact are also *** study sites located near the shores and/or the areas with intensive tourism tend to have higher human impact, especially on poor water quality, which may be linked to the higher severity and composition of coral diseases and signs of compromised health in the Gulf of Thailand. Fish bites are also observed in many study *** severity of fish bites in the Gulf of Thailand is much lower compared to the Andaman Sea. Ko Rawi exhibits the highest severity, following by Ko Surin Nua and Ko Butang. The study sites within marine national park boundaries have a significantly higher severity of fish bites than those outside of the marine national park boundaries. This

关键词： coral diseases fish bites massive Porites management Gulf of Thailand Andaman Sea