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The accurate analysis of the elemental composition plays a crucial role for the research of functional materials. The emitting characteristic X-ray Fluorescence (XRF) photons can be used for precisely discriminating the specified element. The detection accuracy of conventional XRF methodology using semiconductor detector is limited by the energy resolution, thus poses a challenge on accurately scaling the actual energy of each XRF photon. We adopt a novel high-resolution X-ray spectrometer based on the superconducting Transition-edge Sensor (TES) for the XRF spectroscopy measurement of different elements. Properties including high energy resolution, high detection efficiency and precise linearity of the new spectrometer will bring significant benefits in analyzing elemental composition via XRF. In this paper, we study the L-edge emission line profiles of three adjacent rare earth elements with the evenly mixed sample of their oxide components: Terbium, Dysprosium and Holmium. Two orders of magnitude better energy resolution is obtained compared to a commercial silicon drift detector. With this TES-based spectrometer, the spectral lines overlapped or interfered by background can be clearly distinguished, thus making the chemical component analysis more accurate and quantitative. A database of coefficient values for line strength of the spectrum can then be constructed thereafter. Equipped with the novel XRF spectrometer and an established coefficient database, a direct analysis of the composition proportion of a certain element in an unknown sample can be achieved with high accuracy.

Electrochemical energy storage is a process that utilizes chemical reactions to store and release electrical energy in the form of chemical energy. These include lead-acid, lithium-ion, flow, sodium-sulfur batteries, etc., while electrochemical energy storage materials and technologies are the keys to solving the utilization, conversion, and storage of clean energy. In order to solve the problem that the current energy storage technology has an extensive range of energy storage frequency fluctuations in the application process, this paper conducts research on a comprehensive micro-energy storage technology based on multi-type electrochemistry, which improves the stability of energy storage. Based on the introduction of multi-type electrochemical technology, MXene (Ti3C2) was selected as the dispersion liquid, and PVA was used as the gel electrolyte to complete both preparations. The device’s fabrication and assembly are completed based on calculating the rated power, rated capacity, and other parameters of the micro energy storage capacitor. Aiming at the ultra-low frequency oscillation problem that may exist in the energy storage process, this paper develops a micro energy storage control method that participates in primary frequency modulation. The comparison experiment proves that the frequency fluctuation of the new energy storage technology is within the controllable range in practical application, which can effectively improve the stability of energy storage.

By using spatial autoregressive models, this paper mainly studied the limited factors and spatio-temporal prediction of harmful algal blooms (HAB). The environmental factors of sea surface temperature (SST), dissolved organic matter (DOM) and suspended sediment concentration (SSC) were used to model the chlorophyll a (Cha) distribution and the occurrence of HAB. The results indicated that SST had no significant influence on the growth of phytoplankton in May and June, but higher SST in July and August decreased the frequency of occurrence of HAB. SSC was the main limited factor of HAB, and considerably and positively influenced the algal growth and HAB. HAB in Yangtze estuary was mainly caused by nutrients not DOM. The predicted spatial pattern in July 2010 was more dispersed than the actual clustered pattern. This clustered pattern should be driven by the combined impacts of coastal current, Taiwan Worm current and the northward seasonal.

At present, the supply mode of fossil fuel as energy in China has caused more and more damage to the environment. In order to meet the demand for sustainable development, research on the construction of new energy microgrids for wind power generation based on green and low-carbon is proposed. Firstly, the equivalent model of the wind power generation system is established, and then the wind power generation new energy microgrid with a wind turbine as the core is built based on the specific value calculated by the model. Finally, the conventional new energy microgrid construction scheme is selected as the comparative object, and the comparative experiment is carried out to prove the practicability of the method. The comparative experimental results show that the microgrid constructed by the proposed green and low-carbon wind power generation new energy microgrid construction method is superior to the traditional construction scheme in operating power, can meet the green and low-carbon energy development needs, and can provide a reference value for similar research schemes.

Full list of authors: Georgiev, Boris; Pesce, Dominic W.; Broderick, Avery E.; Wong, George N.; Dhruv, Vedant; Wielgus, Maciek; Gammie, Charles F.; Chan, Chi-kwan; Chatterjee, Koushik ; Emami, Razieh; Mizuno, Yosuke; Gold, Roman; Fromm, Christian M.; Ricarte, Angelo; Yoon, Doosoo; Joshi, Abhishek V.; Prather, Ben; Cruz-Osorio, Alejandro; Johnson, Michael D.; Porth, Oliver; Olivares, Héctor; Younsi, Ziri; Rezzolla, Luciano; Vos, Jesse; Qiu, Richard; Nathanail, Antonios; Narayan, Ramesh; Chael, Andrew; Anantua, Richard; Moscibrodzka, Monika; Akiyama, Kazunori; Alberdi, Antxon; Alef, Walter; Algaba, Juan Carlos; Asada, Keiichi; Azulay, Rebecca; Bach, Uwe; Baczko, Anne-Kathrin; Ball, David; Baloković, Mislav; Barrett, John; Bauböck, Michi; Benson, Bradford A.; Bintley, Dan; Blackburn, Lindy; Blundell, Raymond; Bouman, Katherine L.; Bower, Geoffrey C.; Boyce, Hope; Bremer, Michael; Brinkerink, Christiaan D.; Brissenden, Roger; Britzen, Silke; Broguiere, Dominique; Bronzwaer, Thomas; Bustamante, Sandra; Byun, Do-Young; Carlstrom, John E.; Ceccobello, Chiara; Chatterjee, Shami; Chen, Ming-Tang; Chen, Yongjun; Cheng, Xiaopeng; Cho, Ilje; Christian, Pierre; Conroy, Nicholas S.; Conway, John E.; Cordes, James M.; Crawford, Thomas M.; Crew, Geoffrey B.; Cui, Yuzhu; Davelaar, Jordy; De Laurentis, Mariafelicia; Deane, Roger; Dempsey, Jessica; Desvignes, Gregory; Dexter, Jason; Doeleman, Sheperd S.; Dougal, Sean; Dzib, Sergio A.; Eatough, Ralph P.; Falcke, Heino; Farah, Joseph; Fish, Vincent L.; Fomalont, Ed; Ford, H. Alyson; Fraga-Encinas, Raquel; Freeman, William T.; Friberg, Per; Fuentes, Antonio; Galison, Peter; García, Roberto; Gentaz, Olivier; Goddi, Ciriaco; Gómez-Ruiz, Arturo I.; Gómez, José L.; Gu, Minfeng; Gurwell, Mark; Hada, Kazuhiro; Haggard, Daryl; Haworth, Kari; Hecht, Michael H.; Hesper, Ronald; Heumann, Dirk; Ho, Luis C.; Ho, Paul; Honma, Mareki; Huang, Chih-Wei L.; Huang, Lei; Hughes, David H.; Ikeda, Shiro; Impellizzeri, C. M. Violette; Inoue, Makoto; Issaoun, Sara; James, David J.; Jannuzi, Buell T.; Janssen, Michael; Jeter, Britton; Jiang, Wu; Jiménez-Rosales, Alejandra; Jorstad, Svetlana; Jung, Taehyun; Karami, Mansour; Karuppusamy, Ramesh; Kawashima, Tomohisa; Keating, Garrett K.; Kettenis, Mark; Kim, Dong-Jin; Kim, Jae-Young; Kim, Jongsoo; Kim, Junhan; Kino, Motoki; Koay, Jun Yi; Kocherlakota, Prashant; Kofuji, Yutaro; Koch, Patrick M.; Koyama, Shoko; Kramer, Carsten; Kramer, Michael; Krichbaum, Thomas P.; Kuo, Cheng-Yu; La Bella, Noemi; Lauer, Tod R.; Lee, Daeyoung; Lee, Sang-Sung; Lehner, Luis; Leung, Po Kin; Levis, Aviad; Li, Zhiyuan; Lico, Rocco; Lindahl, Greg; Lindqvist, Michael; Lisakov, Mikhail; Liu, Jun; Liu, Kuo; Liuzzo, Elisabetta; Lo, Wen-Ping; Lobanov, Andrei P.; Loinard, Laurent; Lonsdale, Colin J.; Lu, Ru-Sen; Mao, Jirong; Marchili, Nicola; Markoff, Sera; Marrone, Daniel P.; Marscher, Alan P.; Martí-Vidal, Iván; Matsushita, Satoki; Matthews, Lynn D.; Menten, Karl M.; Michalik, Daniel; Mizuno, Izumi; Moran, James M.; Moriyama, Kotaro; Müller, Cornelia; Mus, Alejandro; Musoke, Gibwa; Myserlis, Ioannis; Nadolski, Andrew; Nagai, Hiroshi; Nagar, Neil M.; Nakamura, Masanori; Narayanan, Gopal; Natarajan, Iniyan; Navarro Fuentes, Santiago; Neilsen, Joey; Neri, Roberto; Ni, Chunchong; Noutsos, Aristeidis; Nowak, Michael A.; Oh, Junghwan; Okino, Hiroki; Ortiz-León, Gisela N.; Oyama, Tomoaki; Palumbo, Daniel C. M.; Paraschos, Georgios Filippos; Park, Jongho; Parsons, Harriet; Patel, Nimesh; Pen, Ue-Li; Piétu, Vincent; Plambeck, Richard; PopStefanija, Aleksandar; Pötzl, Felix M.; Preciado-López, Jorge A.; Pu, Hung-Yi; Ramakrishnan, Venkatessh; Rao, Ramprasad; Rawlings, Mark G.; Raymond, Alexander W.; Ripperda, Bart; Roelofs, Freek; Rogers, Alan; Ros, Eduardo; Romero-Cañizales, Cristina; Roshanineshat, Arash; Rottmann, Helge; Roy, Alan L.; Ruiz, Ignacio; Ruszczyk, Chet; Rygl, Kazi L. J.; Sánchez, Salvador; Sánchez-Argüelles, David; Sánchez-Portal, Miguel; Sasada, Mahito; Satapathy, Kaushik; Savolainen, Tuomas; Schloerb, F. Peter; Schonfeld, Jonathan; Schuster, Karl-Friedrich; Shao, Lijing; Shen, Zhiqiang; Small, Des; Sohn, Bong Won; SooHoo, Jason; Souccar, Kamal; Sun, He; Tazaki, Fumie; Tetarenko, Alexandra J.; Tiede, Paul; Tilanus, Remo P. J.; Titus, Michael; Torne, Pablo; Traianou, Efthalia; Trent, Tyler; Trippe, Sascha; Turk, Matthew; van Bemmel, Ilse; van Langevelde, Huib Jan; van Rossum, Daniel R.; Wagner, Jan; Ward-Thompson, Derek; Wardle, John; Weintroub, Jonathan; Wex, Norbert; Wharton, Robert; Wiik, Kaj; Witzel, Gunther; Wondrak, Michael F.; Wu, Qingwen; Yamaguchi, Paul; Young, André; Young, Ken; Yuan, Feng; Yuan, Ye-Fei; Zensus, J. Anton; Zhang, Shuo; Zhao, Guang-Yao; Zhao, Shan-Shan.--This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited., We present a framework for characterizing the spatiotemporal power spectrum of the variability expected from the horizon-scale emission structure around supermassive black holes, and we apply this framework to a library of general relativistic magnetohydrodynamic (GRMHD) simulations and associated general relativistic ray-traced images relevant for Event Horizon Telescope (EHT) observations of Sgr A*. We find that the variability power spectrum is generically a red-noise process in both the temporal and spatial dimensions, with the peak in power occurring on the longest timescales and largest spatial scales. When both the time-averaged source structure and the spatially integrated light-curve variability are removed, the residual power spectrum exhibits a universal broken power-law behavior. On small spatial frequencies, the residual power spectrum rises as the square of the spatial frequency and is proportional to the variance in the centroid of emission. Beyond some peak in variability power, the residual power spectrum falls as that of the time-averaged source structure, which is similar across simulations; this behavior can be naturally explained if the variability arises from a multiplicative random field that has a steeper high-frequency power-law index than that of the time-averaged source structure. We briefly explore the ability of power spectral variability studies to constrain physical parameters relevant for the GRMHD simulations, which can be scaled to provide predictions for black holes in a range of systems in the optically thin regime. We present specific expectations for the behavior of the M87* and Sgr A* accretion flows as observed by the EHT. © 2022. The Author(s). Published by the American Astronomical Society., The Event Horizon Telescope Collaboration thanks the following organizations and programs: National Science Foundation (awards OISE-1743747, AST-1816420, AST-1716536, AST-1440254, AST-1935980); the Black Hole Initiative, which is funded by grants from the John Templeton Foundation and the Gordon and Betty Moore Foundation (although the opinions expressed in this work are those of the author(s) and do not necessarily reflect the views of these foundations); NASA Hubble Fellowship grant HST-HF2-51431.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555; the Academy of Finland (projects 274477, 284495, 312496, 315721); the Agencia Nacional de Investigación y Desarrollo (ANID), Chile via NCN19_058 (TITANs) and Fondecyt 1221421, the Alexander von Humboldt Stiftung; an Alfred P. Sloan Research Fellowship; Allegro, the European ALMA Regional Centre node in the Netherlands, the NL astronomy research network NOVA and the astronomy institutes of the University of Amsterdam, Leiden University, and Radboud University; the Institute for Advanced Study; the China Scholarship Council; Consejo Nacional de Ciencia y Tecnología (CONACYT, Mexico, projects U0004-246083, U0004-259839, F0003-272050, M0037-279006, F0003-281692, 104497, 275201, 263356); the Delaney Family via the Delaney Family John A. Wheeler Chair at Perimeter Institute; Dirección General de Asuntos del Personal Académico-Universidad Nacional Autónoma de México (DGAPA-UNAM, projects IN112417 and IN112820); the European Research Council Synergy Grant "BlackHoleCam: Imaging the Event Horizon of Black Holes" (grant 610058); the Generalitat Valenciana postdoctoral grant APOSTD/2018/177 and GenT Program (project CIDEGENT/2018/021); MICINN Research Project PID2019-108995GB-C22; the European Research Council for advanced grant "JETSET: Launching, propagation and emission of relativistic jets from binary mergers and across mass scales" (grant No. 884631); the Istituto Nazionale di Fisica Nucleare (INFN) sezione di Napoli, iniziative specifiche TEONGRAV; the two Dutch National Supercomputers, Cartesius and Snellius (NWO grant 2021.013); the International Max Planck Research School for Astronomy and Astrophysics at the Universities of Bonn and Cologne; DFG research grant "Jet physics on horizon scales and beyond" (grant No. FR 4069/2-1); Joint Princeton/Flatiron and Joint Columbia/Flatiron Postdoctoral Fellowships, with research at the Flatiron Institute supported by the Simons Foundation; the Japanese Government (Monbukagakusho: MEXT) Scholarship; the Japan Society for the Promotion of Science (JSPS) Grant-in-Aid for JSPS Research Fellowship (JP17J08829); the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (CAS, grants QYZDJ-SSW-SLH057, QYZDJ-SSW-SYS008, ZDBS-LY-SLH011); the Leverhulme Trust Early Career Research Fellowship; the Max-Planck-Gesellschaft (MPG); the Max Planck Partner Group of the MPG and the CAS; the MEXT/JSPS KAKENHI (grants 18KK0090, JP21H01137, JP18H03721, JP18K13594, 18K03709, JP19K14761, 18H01245, 25120007); the Malaysian Fundamental Research Grant Scheme (FRGS) FRGS/1/2019/STG02/UM/02/6; the MIT International Science and Technology Initiatives (MISTI) Funds; the Ministry of Science and Technology (MOST) of Taiwan (103-2119-M-001-010-MY2, 105-2112-M-001-025-MY3, 105-2119-M-001-042, 106-2112-M-001-011, 106-2119-M-001-013, 106-2119-M-001-027, 106-2923-M-001-005, 107-2119-M-001-017, 107-2119-M-001-020, 107-2119-M-001-041, 107-2119-M-110-005, 107-2923-M-001-009, 108-2112-M-001-048, 108-2112-M-001-051, 108-2923-M-001-002, 109-2112-M-001-025, 109-2124-M-001-005, 109-2923-M-001-001, 110-2112-M-003-007-MY2, 110-2112-M-001-033, 110-2124-M-001-007, and 110-2923-M-001-001); the Ministry of Education (MoE) of Taiwan Yushan Young Scholar Program; the Physics Division, National Center for Theoretical Sciences of Taiwan; the National Aeronautics and Space Administration (NASA, Fermi Guest Investigator grant 80NSSC20K1567, NASA Astrophysics Theory Program grant 80NSSC20K0527, NASA NuSTAR award 80NSSC20K0645); the National Institute of Natural Sciences (NINS) of Japan; the National Key Research and Development Program of China (grant 2016YFA0400704, 2017YFA0402703, 2016YFA0400702); the National Science Foundation (NSF, grants AST-0096454, AST-0352953, AST-0521233, AST-0705062, AST-0905844, AST-0922984, AST-1126433, AST-1140030, DGE-1144085, AST-1207704, AST-1207730, AST-1207752, MRI-1228509, OPP-1248097, AST-1310896, AST-1555365, AST-1614868, AST-1615796, AST-1715061, AST-1716327, AST-2034306); the Natural Science Foundation of China (grants 11650110427, 10625314, 11721303, 11725312, 11873028, 11933007, 11991052, 11991053, 12192220, 12192223); NWO grant No. OCENW.KLEIN.113; a fellowship of China Postdoctoral Science Foundation (2020M671266); the Natural Sciences and Engineering Research Council of Canada (NSERC, including a Discovery Grant and the NSERC Alexander Graham Bell Canada Graduate Scholarships-Doctoral Program); the National Youth Thousand Talents Program of China; the National Research Foundation of Korea (the Global PhD Fellowship Grant: grants NRF-2015H1A2A1033752, the Korea Research Fellowship Program: NRF-2015H1D3A1066561, Basic Research Support grant 2019R1F1A1059721, 2022R1C1C1005255); the Dutch Organization for Scientific Research (NWO) VICI award (grant 639.043.513) and Spinoza Prize SPI 78-409; and the YCAA Prize Postdoctoral Fellowship. L.M. gratefully acknowledges support from an NSF Astronomy and Astrophysics Postdoctoral Fellowship under award no. AST-1903847. T.K. is supported by MEXT as "Program for Promoting Researches on the Supercomputer Fugaku" (Toward a unified view of the universe: from large-scale structures to planets, JPMXP1020200109) and JICFuS. R.P.D. and I.N. acknowledge funding by the South African Research Chairs Initiative, through the South African Radio Astronomy Observatory (SARAO, grant ID 77948), which is a facility of the National Research Foundation (NRF), an agency of the Department of Science and Innovation (DSI) of South Africa. We thank the Onsala Space Observatory (OSO) national infrastructure, for the provisioning of its facilities/observational support (OSO receives funding through the Swedish Research Council under grant 2017-00648); the Perimeter Institute for Theoretical Physics (research at Perimeter Institute is supported by the Government of Canada through the Department of Innovation, Science and Economic Development and by the Province of Ontario through the Ministry of Research, Innovation and Science); the Spanish Ministerio de Ciencia e Innovación (grants PGC2018-098915-B-C21, AYA2016-80889-P, PID2019-108995GB-C21, PID2020-117404GB-C21); the University of Pretoria for financial aid in the provision of the new Cluster Server nodes and SuperMicro (USA) for a SEEDING GRANT approved toward these nodes in 2020; the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award for the Instituto de Astrofísica de Andalucía (SEV-2017-0709); the Toray Science Foundation; the Consejería de Economía, Conocimiento, Empresas y Universidad of the Junta de Andalucía (grant P18-FR-1769), the Consejo Superior de Investigaciones Científicas (grant 2019AEP112); the M2FINDERS project, which has received funding by the European Research Council (ERC) under the European Union's Horizon 2020 Research and Innovation Programme (grant agreement No. 101018682); the US Department of Energy (USDOE) through the Los Alamos National Laboratory (operated by Triad National Security, LLC, for the National Nuclear Security Administration of the USDOE (contract 89233218CNA000001); the European Union's Horizon 2020 research and innovation program under grant agreement No. 730562 RadioNet; Shanghai Pilot Program for Basic Research, Chinese Academy of Science, Shanghai Branch (JCYJ-SHFY-2021-013); ALMA North America Development Fund; the Academia Sinica; Chandra DD7-18089X and TM6-17006X; and the GenT Program (Generalitat Valenciana) Project CIDEGENT/2018/021. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), supported by NSF grant ACI-1548562, and CyVerse, supported by NSF grants DBI-0735191, DBI-1265383, and DBI-1743442. The XSEDE Stampede2 resource at TACC was allocated through TG-AST170024 and TG-AST080026N. The XSEDE JetStream resource at PTI and TACC was allocated through AST170028. The simulations were performed in part on the SuperMUC cluster at the LRZ in Garching, on the LOEWE cluster in CSC in Frankfurt, and on the HazelHen cluster at the HLRS in Stuttgart. This research was enabled in part by support provided by Compute Ontario (http://computeontario.ca), Calcul Quebec (http://www.calculquebec.ca), and Compute Canada (http://www.computecanada.ca). C.C. acknowledges support from the Swedish Research Council (VR). We thank the staff at the participating observatories, correlation centers, and institutions for their enthusiastic support. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2016.1.01154.V. ALMA is a partnership of the European Southern Observatory (ESO; Europe, representing its member states), NSF, and National Institutes of Natural Sciences of Japan, together with National Research Council (Canada), Ministry of Science and Technology (MOST; Taiwan), Academia Sinica Institute of Astronomy and Astrophysics (ASIAA; Taiwan), and Korea Astronomy and Space Science Institute (KASI; Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, Associated Universities, Inc. (AUI)/NRAO, and the National Astronomical Observatory of Japan (NAOJ). The NRAO is a facility of the NSF operated under cooperative agreement by AUI. This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under contract No. DE-AC05-00OR22725. We also thank the Center for Computational Astrophysics, National Astronomical Observatory of Japan. Support for this work was also provided by the NASA Hubble Fellowship grant HST-HF2-51431.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555. H.O. and G.M. were supported by Virtual Institute of Accretion (VIA) postdoctoral fellowships from the Netherlands Research School for Astronomy (NOVA). APEX is a collaboration between the Max-Planck-Institut für Radioastronomie (Germany), ESO, and the Onsala Space Observatory (Sweden). The SMA is a joint project between the SAO and ASIAA and is funded by the Smithsonian Institution and the Academia Sinica. The JCMT is operated by the East Asian Observatory on behalf of the NAOJ, ASIAA, and KASI, as well as the Ministry of Finance of China, Chinese Academy of Sciences, and the National Key Research and Development Program (No. 2017YFA0402700) of China and Natural Science Foundation of China grant 11873028. Additional funding support for the JCMT is provided by the Science and Technologies Facility Council (UK) and participating universities in the UK and Canada. Simulations were performed in part on the SuperMUC cluster at the LRZ in Garching, on the LOEWE cluster in CSC in Frankfurt, on the HazelHen cluster at the HLRS in Stuttgart, and on the Pi2.0 and Siyuan Mark-I at Shanghai Jiao Tong University. The computer resources of the Finnish IT Center for Science (CSC) and the Finnish Computing Competence Infrastructure (FCCI) project are acknowledged. J.O. was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2021R1A6A3A01086420; 2022R1C1C1005255). We thank Martin Shepherd for the addition of extra features in the Difmap software that were used for the CLEAN imaging results presented in this paper. The computing cluster of Shanghai VLBI correlator supported by the Special Fund for Astronomy from the Ministry of Finance in China is acknowledged. This work was supported by the Brain Pool Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (019H1D3A1A01102564). This research is part of the Frontera computing project at the Texas Advanced Computing Center through the Frontera Large-Scale Community Partnerships allocation AST20023. Frontera is made possible by National Science Foundation award OAC-1818253. This research was carried out using resources provided by the Open Science Grid, which is supported by the National Science Foundation and the U.S. Department of Energy Office of Science. The LMT is a project operated by the Instituto Nacional de Astrófisica, Óptica, y Electrónica (Mexico) and the University of Massachusetts at Amherst (USA). The IRAM 30 m telescope on Pico Veleta, Spain, is operated by IRAM and supported by CNRS (Centre National de la Recherche Scientifique, France), MPG (Max-Planck-Gesellschaft, Germany), and IGN (Instituto Geográfico Nacional, Spain). The SMT is operated by the Arizona Radio Observatory, a part of the Steward Observatory of the University of Arizona, with financial support of operations from the State of Arizona and financial support for instrumentation development from the NSF. Support for SPT participation in the EHT is provided by the National Science Foundation through award OPP-1852617 to the University of Chicago. Partial support is also provided by the Kavli Institute of Cosmological Physics at the University of Chicago. The SPT hydrogen maser was provided on loan from the GLT, courtesy of ASIAA. Support for this work was provided by NASA through the NASA Hubble Fellowship grant No. HST-HF2-51494.001 awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5–26555. Jongho Park acknowledges financial support through the EACOA Fellowship awarded by the East Asia Core Observatories Association, which consists of the Academia Sinica Institute of Astronomy and Astrophysics, the National Astronomical Observatory of Japan, Center for Astronomical Mega-Science, Chinese Academy of Sciences, and the Korea Astronomy and Space Science Institute. The EHTC has received generous donations of FPGA chips from Xilinx Inc., under the Xilinx University Program. The EHTC has benefited from technology shared under open-source license by the Collaboration for Astronomy Signal Processing and Electronics Research (CASPER). The EHT project is grateful to T4Science and Microsemi for their assistance with Hydrogen Masers. This research has made use of NASA's Astrophysics Data System. We gratefully acknowledge the support provided by the extended staff of the ALMA, both from the inception of the ALMA Phasing Project through the observational campaigns of 2017 and 2018. We would like to thank A. Deller and W. Brisken for EHT-specific support with the use of DiFX.

With the development of cloud computing, the data center network is undergoing great changes. The traditional wired data center network needs a large number of wired links, so it takes huge resources to deploy. For the wireless data center network, although the line installation is simple and the maintenance cost is reduced, the wireless transmission signal is easily blocked. Therefore, this paper proposes a hybrid data center network VDCell based on VLC link, and designs a rule to connect wireless links. Compared with the original DCell topology, it has the following advantages: First of all, the VLC link can be directly installed and used, without centralized control in VDCell, so no additional equipment is needed. Secondly, it is only necessary to add wireless links to the original structure, and the design rules are used to construct the structure, which shortens the communication path length between servers and is very simple to deploy. The increase of data links makes the structure more fault-tolerant. In addition, this paper also proposes a unicast routing algorithm.

The microstructural responses of In0.32Ga0.68N and In0.9Ga0.1N films to 2.25 GeV Xe ion irradiation have been investigated using x-ray diffraction, Raman scattering, ion channeling and transmission electron microscopy. It was found that the In-rich In0.9Ga0.1N is more susceptible to irradiation than the Ga-rich In0.32Ga0.68N. Xe ion irradiation with a fluence of 7 × 1011 ions⋅cm−2 leads to little damage in In0.32Ga0.68N but an obvious lattice expansion in In0.9Ga0.1N. The level of lattice disorder in In0.9Ga0.1N increases after irradiation, due to the huge electronic energy deposition of the incident Xe ions. However, no Xe ion tracks were observed to be formed, which is attributed to the very high velocity of 2.25 GeV Xe ions. Point defects and/or small defect clusters are probably the dominant defect type in Xe-irradiated In0.9Ga0.1N.

A high-efficiency and high-power vertical-cavity surface-emitting laser (VCSEL) side-pumped rod Nd:YAG laser with temperature adaptability are demonstrated. The VCSEL side-pumped laser module is designed and optimized. Five VCSEL arrays are symmetrically located around the laser rod and a large size diffused reflection chamber is designed to ensure a uniform pump distribution. Furthermore, the absorbed pump power distribution of the rod is simulated to verify the uniformity of the pump absorption. Finally, a proof-of-principle experiment is performed in short linear cavity laser with single laser module. A continuous-wave output power of 658 W at 1064 nm is obtained, the corresponding optical-to-optical efficiency is 52.6%, and the power variations are ±0.7% over 400 s and ±3.1% over the temperature range from 16 °C to 26 °C. To the best of our knowledge, this is the highest output power and the highest optical-to-optical efficiency ever reported for VCSEL pumped solid-state lasers. By inserting a telescopic module into the cavity and optimizing the TEM00 mode volume, the average beam quality is measured to be M 2 = 1.34 under an output power of 102 W. The experimental results reveal that such a high power rod laser module with temperature stability is appropriate for field applications.

This work is to retrieve emission-line spectra from the “Unknown” data set in LAMOST DR7 V1.2, most of which are low signal-to-noise ratios spectra. In the work, we perform emission line search and redshift calculations on the Unknown data set to get possible emission line galaxy spectra. Taking the galaxy spectra released by LAMOST as templates, the Product Quantization (PQ) based approximate nearest neighbor (ANN) search is used to retrieve the nearest neighbors of each spectrum. We keep the spectra for which the calculated redshift and the published redshift of the template meet the threshold, and 16,188 spectra with emission lines are obtained from the LAMOST DR7 Unknown data set. After visual inspection of spectra 10,266 spectra are left, in which 5828 spectra are identified as emission-line galaxies, 1782 spectra show ionization nebula features, and other 2656 are not clearly classified. Among 5828 spectra, 5720 can be found in Strasbourg astronomical Data Center catalog, Sloan Digital Sky Survey catalog, or NASA/IPAC Extragalactic Database catalog. The 108 spectra (corresponding to 106 unique coordinates of R.A. and decl.) which have no record in these three databases are new discoveries; for the 1782 spectra showing ionization nebula features, most of them have radial velocities less than 150 kilometers per second. We check them with the latest version of WISE H ii catalog V2.0 (short for HIICat V2) and 985 out of the 1782 spectra belong to 72 H ii regions. Of these H ii regions, 43 were previously identified while the other 29 are newly identified in this work including 797 newly observed spectra. Besides, there are still 2656 spectra that cannot be clearly classified although they have obvious emission lines and with small redshift. Finally, 106 new emission-line galaxies and 29 new Galactic H ii regions are identified, and we conclude that the ANN method sped up by the PQ algorithm is efficient in solving the problem of pairing spectra with massive data set to figure out their classes. We present our result at the link http://paperdata.china-vo.org/LY_paper/Work2/pressWork2_last.zip.

In order to avoid the management blind area of environmental temperature, humidity and lighting in non daily office sites such as operation stations and reception centers. It is necessary to strengthen intelligent management and control. An intelligent control device based on narrow-band Internet of things is proposed to monitor the environmental temperature and humidity of the station on-line. The automatic regulation of ventilation and air conditioning devices is realized by intelligent algorithm. The intelligent control of lighting, temperature control and related auxiliary facilities of the site station can be realized, 4G cloud service can be realized, and remote monitoring and remote control can be realized.

Due to the fact that the space is becoming increasingly congested, there is a high requirement for the orbit prediction accuracy of space targets to support collision warning tasks. This is especially true for space debris with high area-to-mass ratio and low orbit altitude. This paper focuses on the along-track position error caused by the atmospheric density error and area-to-mass ratio error for targets with near-circular orbit in the orbit prediction. We derive a semi-analytical expression to describe the along-track position error, and the expression’s validity is evaluated by a goodness-of-fit index compared with the simulated “true” along-track position error. The simulation is based on Encke’s special perturbation method, in which the drag error is treated as a perturbation. The drag error is modeled by the difference between the JB2008 and MISIS density model and the sinusoidal oscillation error model concerning the inexact area-to-mass ratio. Furthermore, targets with various orbit altitudes ranging from 300km to 800km are selected to investigate whether the along-track position error can meet the collision warning requirements.

To improve the parameter robustness of the open-winding permanent magnet synchronous motor (OW-PMSM), this paper proposes an improved model-free predictive current control (MFPCC) method. First, the first-order ultra-local model of OW-PMSM is established, which does not contain any motor parameter. Secondly, a sliding mode observer (SMO) is introduced into the model to estimate the current in d-q-0 axis. Then, to suppress the torque ripple generated by the zero-sequence current (ZSC), the central hexagonal modulation strategy and the q-axis current injection method are combined, and the compensation current that needs to be injected into the q-axis is calculated according to the estimated value of ZSC. Finally, after considering the one-step delay, the voltage reference at the next instant is calculated based on the estimated values of d-q axis current and compensation current. Simulation and experimental results indicate that the proposed method can improve the parameter robustness of OW-PMSM, and the performance of current and torque has been improved under various parameter mismatch conditions.

Ballistic target tracking and identification is a key task for missile defense systems. A vital problem in ballistic target identification is how to estimate the target mass-to-drag ratio fast and accurately. The reentry phase of a ballistic missile is the last stage of its flight, and the reentry trajectory is significantly affected by the atmospheric drag. Based on the constraints of space flight dynamics, this paper proposes a two-stage algorithm to estimate the mass-to-drag ratio. This algorithm first estimates the position and velocity of the target in the free flight stage by using the least-squares method, and then estimates the mass-to-drag ratio of the target by using the radial range measurements from the reentry stage. Several trajectories of a ballistic target under different mass-to-drag ratios are simulated, and the proposed algorithm is verified using these simulated trajectories.

In order to reveal the hydraulic reasons for the uneven distribution of water flow and velocity in the high-efficiency clarification tank, and the hydraulic reasons for the deposition of sediment on one side, CFD was used to simulate the overall tank. The three-dimensional simulation results showed that without any baffle, the velocity was extremely uneven, and the rotation of the stirring blade around the axis produced a velocity loop, which resulted in a large backflow of the velocity. There were obvious differences in flocs and water flow through the two holes. After adding the existing baffles, the water flow and floc concentration could be much more uniform, but there was still sludge sediment on one side. After further lengthening the existing baffles outside the cylinder and adding 45° baffles in the transition section of the coagulation tank and the sedimentation tank, the inconsistency of flow velocity and floc concentration could be basically solved.

At present, in terms of power marketing measurement training, there are problems such as measurement wiring discrimination inconvenience, drawing inconvenience, wiring display time consuming, resulting in the measurement wiring training is not in place. The article first of the three phase three line power meter and three phase four line power meter correct wiring mode and phasor diagram, and then a special tool for the vector analysis used in the training is designed, which can not only solve the above problems, but also replace the manual drawing of the vector map, which has a good practical effect on the power marketing measurement training, enables the students to learn the measurement wiring more intuitively.

Because ordinary users cannot quickly obtain the three-dimensional space position of aircraft in the airport terminal area through a two-dimensional display navigation map, the aircraft surveillance simulation system in the airport terminal area based on virtual reality technology is designed. Through analyzing the Automatic Dependent Surveillance-Broadcast (ADS-B) data, the aircraft motion model is established. The three-dimensional aircraft surveillance simulation system for the airport terminal area is realized by Unreal Engine 4 (UE4). Especially, the changes in flight track and flight attitude about aircraft in the three-dimensional scene are designed. The results show that the aircraft movements can be visualized smoothly and correctly based on ADS-B data. It is helpful for users to observe the aircraft of the airport terminal area and analyze the operation status of the plane.

This paper introduces the problems of poor signal condition of a single time source in time synchronization or error in time source switching in the power system. It adopts the two-clock mode timing scheme of BeiDou 2 synchronous satellite and GPS synchronous satellite to ensure the stable output of the main clock within a certain accuracy. The system takes full advantage of the field programmable gate array (FPGA) hardware method, aligns the internal clock lock signal with the input second pulse phase, and proposes an improved method for the problem of large clock synchronization deviation based on the network, which proves the effectiveness and superiority of the system to accurately output the pulse and provide reliable time synchronization for the power dispatching system.

Histopathology currently acts as a gold standard for human prostate cancer (PCa) diagnosis. However, the subjective nature of histopathology leads to inevitable discordance among pathologists. Specifically, the inter-observer discordance could be up to 40% for the differentiation between Gleason score 6 (low-grade) and 7 (high-grade) of PCa. According to clinical guidelines, patients with high-grade PCa need to be actively treated, while patients with low-grade PCa could undergo active surveillance due to its slowly growing feature. Therefore, differentiating high-grade and low-grade PCa is an urgent clinical need. By integrating stimulated Raman scattering microscopy and confocal Raman spectroscopy, our previous study found the aberrant cholesteryl ester (CE) accumulation in human PCa tissues. However, no significant difference in CE accumulation between the low-grade and high-grade PCa was found, primarily because the previous study only analyzed the composition of manually selected lipid droplets (LDs) without quantitative analysis of the whole field of view. Here, we employed hyperspectral stimulated Raman scattering (HSRS) microscopy to test the hypothesis of CE as a marker for differentiation of low-grade and high-grade human PCa. First, lipid, lipofuscin, and protein were quantitatively mapped in human prostate tissues based on HSRS imaging of C–H vibrational region and multivariate curve resolution analysis. Then, within the lipid channel, CE percentage and unsaturation level of LDs were quantitatively mapped according to the height ratio between Raman bands at 2870 and 2850 cm−1, and between Raman bands at 3006 and 2850 cm−1, respectively. In total of 6 normal prostate tissues, 9 low-grade and 9 high-grade PCa tissues from patients, we found lipofuscin accumulation in all the normal prostate but none in PCa. While all the high-grade PCa tissues had LD accumulation, only 3 low-grade PCa tissues had LD accumulation. Notably, among all the PCa tissues with LD accumulation, no significant difference in LD amount was found between low-grade and high-grade PCa. Fortunately, both CE percentage and unsaturation level of the LDs were significantly different between low-grade and high-grade PCa. Furthermore, it was shown that CE percentage could differentiate low-grade and high-grade PCa with high sensitivity and specificity. Taken together, our study may provide a new opportunity towards more accurate PCa diagnosis.

In this study, the effects of thermal-rate treatment (TRT) and modification of Ce on the microstructure and mechanical properties of A356 alloy were investigated. The results showed that the microstructure of A356 alloy was improved after TRT and modification of Ce. The α-Al was refined significantly and the eutectic Si transformed from needle-like shape to granular-like shape. When the content of Ce increased to 0.5%, the grain size of α-Al of A356 alloy began to increase and the dendrites became coarse. When the Ce content was 0.4%, the tensile strength and yield strength of A356 alloy were 183MPa and 124 MPa, respectively. The mechanism of (TRT+Ce) on the grain refinement of α-Al and modification of eutectic Si was discussed.

The LAMOST II survey began in the fall of 2018, and LAMOST formally released the obtained medium-resolution spectra (MRS) as well as catalogs of stellar parameters and radial velocities (RV) derived from the MRS in the seventh LAMOST data release (DR7). Compared with the RVs and parameters from high-resolution SDSS14/APOGEE spectra, nearly no RV discrepancy was found, with only dispersion around one km s−1. The T eff of MRS was 27.79 K systematically lower than that of APOGEE, and the 1σ difference was approximately 60.40 K. For metallicity, the [Fe/H] of the MRS was 0.11 dex poorer than that of APOGEE, with a dispersion of 0.07 dex. More apparently, the offset of log g was 0.14 dex, and the scatter was 0.23 dex. The gravities of APOGEE have been corrected through seismological data. Similarly, in this study, we tried to calibrate LAMOST MRS log g with the Kepler data for red clump stars and red giant branch stars based on two fitted calibration relations. In addition, we found log g of a small fraction late-K type giants mistakenly measured as dwarfs, and vice versa, on the HR diagram generated with LAMOST T eff and Gaia absolute magnitudes. This was because the MRS parameters were measured from blue band spectra only. The measurements of log g for late-K stars can be significantly improved by adding red spectra.

We present a cooling scheme with a tripod configuration atomic ensemble trapped in an optomechanical cavity. With the employment of two different quantum interference processes, our scheme illustrates that it is possible to cool a resonator to its ground state in the strong cavity–atom coupling regime. Moreover, with the assistance of one additional energy level, our scheme takes a larger cooling rate to realize the ground state cooling. In addition, this scheme is a feasible candidate for experimental applications.

Phase modulation is a crucial step when the frequency-based wavefront optimization technique is exploited to measure the optical transmission matrix (TM) of a scattering medium. We report a simple but powerful method, direct digital frequency synthesis (DDS) technology to modulate the phase front of the laser and measure the TM. By judiciously modulating the phase front of a He–Ne laser beam, we experimentally generate a high quality focus at any targeted location through a 2 mm thick 120 grit ground glass diffuser, which is commercially used in laser display and laser holographic display for improving brightness uniformity and reducing speckle. The signal to noise ratio (SNR) of the clear round focus is ∼ 50 and the size is about 44 μm. Our study will open up new avenues for enhancing light energy delivery to the optical engine in laser TV to lower the power consumption, phase compensation to reduce the speckle noise, and controlling the lasing threshold in random lasers.

In recent years, with the continuous improvement of China’s economic level, Chinese people’s living standards are also improving, so that the vigorous development of the e-commerce industry and the number of the total amount of social logistics have increased year by year, which has brought great impetus to the development of the logistics industry. Based on the background, it requires a scientific and reasonable forecasting result of the total amount of logistics for the logistics industry investment. This paper employs an ARIMA and BPNN combined method to forecast the total logistics situation during the “14th Five-Year Plan” period, the results show that the combination forecasting method can take into account the advantages of each single forecast model, and its forecast effect is more ideal.

The USB universal serial bus is widely used in host computer control and data information transmission due to its plug-and-play, hot-swap support, and flexible use. However, due to cable loss and USB protocol restrictions, high-speed USB signals can only support a transmission distance of 5 meters. In this paper, there shows an engineering application design of the signal transmission scheme based on the USB signal processing chip CH317. Convert hi-speed USB signal into optical Ethernet signal to achieve long-distance transmission of high-speed USB signals. Since there is no test standard at the application layer for hi-speed USB signal, in this paper design a complete test scheme for this transmission method at the hardware layer and application layer according to the existing test standards of hi-speed USB signal and Ethernet. It has certain reference significance for the application of hi-speed USB signal long-distance transmission in engineering.

Pile foundation has unique advantage in reducing the settlement of the upper structure and improving the foundation bearing capacity, while Drilling with PHC Pipe Cased Pile (DPC Pile) is a newly developed non-extruded soil PHC tubular pile which integrates drilling-pile sinking-dumping simultaneously to solve the pile sinking problem of large diameter (800 ∼ 1400mm) pipe pile. It solves the problem of pile sinking caused by large pile diameter or hard soil layer, breaks the situation that the pipe pile foundation can only be limited to small diameter and size, and broadens the applicable scope of engineering geology of pipe pile. It realizes the full rock-socketed of the pile tip (which can enter the middle and weak weathering stratum), improves the bearing capacity of single pile, and gives full play to the advantages of pipe pile material with higher strength. It has little damage to the pipe pile and little noise, being relatively environmentally friendly, as well as plays a major demonstration role in leading the new direction of the development of green, energy-saving and environmental protection pile foundation, conforming with the advanced development trend of upgrading traditional advantageous industries to high-tech manufacturing and construction technology with promising market.

In recent years, with the application of Permanent-magnet synchronous motor (PMSM) has been wildly appeared in many industrial areas, sensorless control method of PMSM is being a research hotpot in last two decades. This paper propose a novel speed sensorless control method for SPMSM, which consists of model adaptive reference speed (MARS) sensorless method and Recursive Least Square (RLS) parameter identification method, we use RLS method to identify the inductance and take the estimated inductance value to MARS control and the fundamental control method, finally we use the estimated speed and position value as feedback to make a close loop control frame. This novel method can successfully make the whole control system operate using the estimated speed and position value as feedback meanwhile overcome the flaw that control frame is sensitive with the parameters. We use Matlab/Simulink to implement simulation and the results could prove this method’s feasibility.

With large number of wind power and grid-connected photovoltaic system, the ratios of renewable power greatly increase. However, random variations of the meteorological environment usually have a huge impact on the output of the renewable power, also the performance and stability of power grid. Hence, a local meteorology real-time monitoring technique is really needed. In this paper, a local micro-meteorological monitoring system is proposed, which takes temperature, wind speed, wind direction, and illumination intensity into account. The measurements would provide a reliable real-time meteorological data for power supply forecast and operation reference of distribution network. The hardware and software design are discussed. Finally, a prototype is developed.

A method combining CFD and field test is applied to study the influence of geometric parameters of double-storey sedimentation tank on hydraulic characteristics. The results show that the flow field of the sedimentation tank is close to the clear water sedimentation tank and the effect of particles on water flow is relatively small. Longer width, longer length, upper and lower stories with comparable depths, and longer sumps are beneficial for reducing the particle concentration at the outlet. The velocity of the bottom is small and the velocity of the upper storey is large. The floc particles in the front section are larger and the sedimentation speed is larger, and the flocs in the rear section are opposite.

The traditional end-to-end task-oriented dialogue models are based on complex recurrent or convolutional neural networks that include an encoder and a decoder. But in the case of large amounts of data, there are many types of questions. It performs poorly when answering multiple types of questions, memory information cannot effectively record all the sentence information of the context. In view of the above this, this article uses a modified transformer model to overcome the problems mentioned in dialogue tasks. Transformer is a model constructed using attention mechanisms, which completely discards the method of RNN (recurrent neural networks), and its structure includes two sub-parts of Encoder and decoder. It uses residual network, batch normalization, and self-attention mechanism to build the model structure, uses Positional Encoding to capture sentence information, which can speed up model training convergence and capture Longer sentence information. In this paper, we modified the activation function in the transformer and use label smoothing to optimize the training to make the model’s expressive ability better than previous.