检索结果-内蒙古大学图书馆

arXiv 2021年

作者： Sirunyan, A.M. Tumasyan, A. Adam, W. Bergauer, T. Dragicevic, M. Erö, J. Escalante Del Valle, A. Frühwirth, R. Jeitler, M. Krammer, N. Lechner, L. Liko, D. Madlener, T. Mikulec, I. Pitters, F.M. Rad, N. Schieck, J. Schöfbeck, R. Spanring, M. Templ, S. Waltenberger, W. Wulz, C.-E. Zarucki, M. Chekhovsky, V. Litomin, A. Makarenko, V. Suarez Gonzalez, J. Darwish, M.R. de Wolf, E.A. Di Croce, D. Janssen, X. Kello, T. Lelek, A. Pieters, M. Rejeb Sfar, H. van Haevermaet, H. van Mechelen, P. van Putte, S. van Remortel, N. Blekman, F. Bols, E.S. Chhibra, S.S. D'Hondt, J. de Clercq, J. Lontkovskyi, D. Lowette, S. Marchesini, I. Moortgat, S. Morton, A. Python, Q. Tavernier, S. van Doninck, W. van Mulders, P. Beghin, D. Bilin, B. Clerbaux, B. de Lentdecker, G. Dorney, B. Favart, L. Grebenyuk, A. Kalsi, A.K. Makarenko, I. Moureaux, L. Pétré, L. Popov, A. Postiau, N. Starling, E. Thomas, L. Vander Velde, C. Vanlaer, P. Vannerom, D. Wezenbeek, L. Cornelis, T. Dobur, D. Gruchala, M. Khvastunov, I. Niedziela, M. Roskas, C. Skovpen, K. Tytgat, M. Verbeke, W. Vermassen, B. Vit, M. Bruno, G. Bury, F. Caputo, C. David, P. Delaere, C. Delcourt, M. Donertas, I.S. Giammanco, A. Lemaitre, V. Mondal, K. Prisciandaro, J. Taliercio, A. Teklishyn, M. Vischia, P. Wertz, S. Wuyckens, S. Alves, G.A. Hensel, C. Moraes, A. Aldá Júnior, W.L. Belchior Batista Das Chagas, E. Brandao Malbouisson, H. Carvalho, W. Chinellato, J. Coelho, E. da Costa, E.M. da Silveira, G.G. de Jesus Damiao, D. Fonseca De Souza, S. Martins, J. Matos Figueiredo, D. Medina Jaime, M. Mora Herrera, C. Mundim, L. Nogima, H. Rebello Teles, P. Sanchez Rosas, L.J. Santoro, A. Silva Do Amaral, S.M. Sznajder, A. Thiel, M. Torres Da Silva De Araujo, F. Vilela Pereira, A. Bernardes, C.A. Calligaris, L. Fernandez Perez Tomei, T.R. Gregores, E.M. Lemos, D.S. Mercadante, P.G. Novaes, S.F. Padula, Sandra S. Aleksandrov, A. Antchev, G. Atanasov, I. Hadjiiska, R. Iaydjiev, P. Misheva, M. Rodozov, M. Shopova, M. Sultanov, G. Bonchev, M. Dimitrov, A. Ivanov, T. Litov, L. Pavlov, B. Petkov, Yerevan Physics Institute Yerevan Armenia Institut für Hochenergiephysik Wien Austria Institute for Nuclear Problems Minsk Belarus Universiteit Antwerpen Antwerpen Belgium Vrije Universiteit Brussel Brussel Belgium Université Libre de Bruxelles Bruxelles Belgium Ghent University Ghent Belgium Université Catholique de Louvain Louvain-la-Neuve Belgium Centro Brasileiro de Pesquisas Fisicas Rio de Janeiro Brazil Universidade do Estado do Rio de Janeiro Rio de Janeiro Brazil Universidade Estadual Paulista São Paulo Brazil Universidade Federal do ABC São Paulo Brazil Institute for Nuclear Research and Nuclear Energy Bulgarian Academy of Sciences Sofia Bulgaria University of Sofia Sofia Bulgaria Beihang University Beijing China Department of Physics Tsinghua University Beijing China Institute of High Energy Physics Beijing China State Key Laboratory of Nuclear Physics and Technology Peking University Beijing China Sun Yat-Sen University Guangzhou China Institute of Modern Physics Key Laboratory of Nuclear Physics and Ion-beam Application MOE Fudan University Shanghai China Zhejiang University Hangzhou China Universidad de Los Andes Bogota Colombia Universidad de Antioquia Medellin Colombia University of Split Faculty of Electrical Engineering Mechanical Engineering and Naval Architecture Split Croatia University of Split Faculty of Science Split Croatia Institute Rudjer Boskovic Zagreb Croatia University of Cyprus Nicosia Cyprus Charles University Prague Czech Republic Escuela Politecnica Nacional Quito Ecuador Universidad San Francisco de Quito Quito Ecuador Academy of Scientific Research and Technology of the Arab Republic of Egypt Egyptian Network of High Energy Physics Cairo Egypt Center for High Energy Physics CHEP-FU Fayoum University El-Fayoum Egypt National Institute of Chemical Physics and Biophysics Tallinn Estonia Department of Physics University of Helsinki Helsinki Finland Helsinki Institute of Physics Helsinki Finland Lappe

A search for Wγ resonances in the mass range between 0.7 and 6.0 TeV is presented. The W boson is reconstructed via its hadronic decays, with the final-state products forming a single large-radius jet, owing to a high Lorentz boost of the W boson. The search is based on proton-proton collision data at √s = 13 TeV, corresponding to an integrated luminosity of 137 fb-1, collected with the CMS detector at the LHC in 2016–2018. The Wγ mass spectrum is parameterized with a smoothly falling background function and examined for the presence of resonance-like signals. No significant excess above the predicted background is observed. Model-specific upper limits at 95% confidence level on the product of the cross section and branching fraction to the Wγ channel are set. Limits for narrow resonances and for resonances with an intrinsic width equal to 5% of their mass, for spin-0 and spin-1 hypotheses, range between 0.17 fb at 6.0 TeV and 55 fb at 0.7 TeV. These are the most restrictive limits to date on the existence of such resonances over a large range of probed masses. In specific heavy scalar (vector) triplet benchmark models, narrow resonances with masses between 0.75 (1.15) and 1.40 (1.36) TeV are excluded for a range of model parameters. Model-independent limits on the product of the cross section, signal acceptance, and branching fraction to the Wγ channel are set for minimum Wγ mass thresholds between 1.5 and 8.0 TeV. © 2021, CC BY.

关键词： Resonance

来源：评论

学校读者我要写书评

暂无评论

Code Level Context Sensitivity Exploration Algorithm

Code Level Context Sensitivity Exploration Algorithm

引用

2015 4th International Conference on Computer, Mechatronics, Control and Electronic engineering (ICCMCEE 2015)

作者： Yan Lijing Shan Zheng Xu Xiaoyan Xue Fei The State Key Laboratory of Mathematical Engineering and Advanced Computing Information Engineering University

ISBN: (纸本)9781510813465

The context sensitivity is an important property in program analysis which can improve the analysis accuracy of the function call context of the source codes and helps to improve the abilities of the compiler optimization and verification procedures. The automata model based on the function call of the program source code is an effective method of modeling the behaviors of the current software, but this method does not consider the context sensitivity of the software function calls. To solve this problem, on the base of high-performance open source compiler Open64, we achieve a source code level context sensitivity exploration algorithm to analyze the relationships between the points of the function calls. Using the iterator, by the circulating way, the algorithm traverses the calling relationships between functions and obtains the context sensitive information analysis results. With this method, it can guide the source code modeling of using the single context sensitivity or the mixed context sensitivity models. In the benchmark sets SPEC2006 and NPB3.3.1, we verify the correctness of the algorithm, and the results show that the proposed algorithm can detect the context sensitivity of the source code level, and the hybrid context sensitivity modeling approach which we used, comparing with other modeling methods, has had a higher accuracy.

关键词： Behavior model Function call graph Context sensitivity Source code level Inter-procedure analysis

来源：评论

学校读者我要写书评

暂无评论

First search for exclusive diphoton production at high mass with tagged protons in proton-proton collisions at √s= 13 TeV

arXiv

引用

arXiv 2021年

作者： Sirunyan, A.M. Tumasyan, A. Adam, W. Bergauer, T. Dragicevic, M. Erö, J. Escalante Del Valle, A. Frühwirth, R. Jeitler, M. Krammer, N. Lechner, L. Liko, D. Madlener, T. Mikulec, I. Pitters, F.M. Rad, N. Schieck, J. Schöfbeck, R. Spanring, M. Templ, S. Waltenberger, W. Wulz, C.-E. Zarucki, M. Chekhovsky, V. Litomin, A. Makarenko, V. Suarez Gonzalez, J. Darwish, M.R. de Wolf, E.A. Di Croce, D. Janssen, X. Kello, T. Lelek, A. Pieters, M. Rejeb Sfar, H. van Haevermaet, H. van Mechelen, P. van Putte, S. van Remortel, N. Blekman, F. Bols, E.S. Chhibra, S.S. D’Hondt, J. de Clercq, J. Lontkovskyi, D. Lowette, S. Marchesini, I. Moortgat, S. Morton, A. Python, Q. Tavernier, S. van Doninck, W. van Mulders, P. Beghin, D. Bilin, B. Clerbaux, B. de Lentdecker, G. Dorney, B. Favart, L. Grebenyuk, A. Kalsi, A.K. Makarenko, I. Moureaux, L. Pétré, L. Popov, A. Postiau, N. Starling, E. Thomas, L. Vander Velde, C. Vanlaer, P. Vannerom, D. Wezenbeek, L. Cornelis, T. Dobur, D. Gruchala, M. Khvastunov, I. Niedziela, M. Roskas, C. Skovpen, K. Tytgat, M. Verbeke, W. Vermassen, B. Vit, M. Bruno, G. Bury, F. Caputo, C. David, P. Delaere, C. Delcourt, M. Donertas, I.S. Giammanco, A. Lemaitre, V. Mondal, K. Prisciandaro, J. Taliercio, A. Teklishyn, M. Vischia, P. Wertz, S. Wuyckens, S. Alves, G.A. Hensel, C. Moraes, A. Aldá Júnior, W.L. Belchior Batista Das Chagas, E. Brandao Malbouisson, H. Carvalho, W. Chinellato, J. Coelho, E. da Costa, E.M. da Silveira, G.G. de Jesus Damiao, D. Fonseca De Souza, S. Martins, J. Matos Figueiredo, D. Medina Jaime, M. Mora Herrera, C. Mundim, L. Nogima, H. Rebello Teles, P. Sanchez Rosas, L.J. Santoro, A. Silva Do Amaral, S.M. Sznajder, A. Thiel, M. Torres Da Silva De Araujo, F. Vilela Pereira, A. Bernardes, C.A. Calligaris, L. Fernandez Perez Tomei, T.R. Gregores, E.M. Lemos, D.S. Mercadante, P.G. Novaes, S.F. Padula, Sandra S. Aleksandrov, A. Antchev, G. Atanasov, I. Hadjiiska, R. Iaydjiev, P. Misheva, M. Rodozov, M. Shopova, M. Sultanov, G. Bonchev, M. Dimitrov, A. Ivanov, T. Litov, L. Pavlov, B. Yerevan Physics Institute Yerevan Armenia Institut für Hochenergiephysik Wien Austria Institute for Nuclear Problems Minsk Belarus Universiteit Antwerpen Antwerpen Belgium Vrije Universiteit Brussel Brussel Belgium L'Université libre de Bruxelles Bruxelles Belgium Ghent University Ghent Belgium Université Catholique de Louvain Louvain-la-Neuve Belgium Centro Brasileiro de Pesquisas Fisicas Rio de Janeiro Brazil Universidade do Estado do Rio de Janeiro Rio de Janeiro Brazil Universidade Estadual Paulista São Paulo Brazil Universidade Federal do ABC São Paulo Brazil Institute for Nuclear Research and Nuclear Energy Bulgarian Academy of Sciences Sofia Bulgaria University of Sofia Sofia Bulgaria Beihang University Beijing China Department of Physics Tsinghua University Beijing China Institute of High Energy Physics Beijing China State Key Laboratory of Nuclear Physics and Technology Peking University Beijing China Sun Yat-Sen University Guangzhou China Institute of Modern Physics and Key Laboratory of Nuclear Physics and Ion-beam Application MOE Fudan University Shanghai China Zhejiang University Hangzhou China Universidad de Los Andes Bogota Colombia Universidad de Antioquia Medellin Colombia University of Split Faculty of Electrical Engineering Mechanical Engineering and Naval Architecture Split Croatia University of Split Faculty of Science Split Croatia Institute Rudjer Boskovic Zagreb Croatia University of Cyprus Nicosia Cyprus Charles University Prague Czech Republic Escuela Politecnica Nacional Quito Ecuador Universidad San Francisco de Quito Quito Ecuador Academy of Scientific Research and Technology of the Arab Republic of Egypt Egyptian Network of High Energy Physics Cairo Egypt Center for High Energy Physics CHEP-FU Fayoum University El-Fayoum Egypt National Institute of Chemical Physics and Biophysics Tallinn Estonia Department of Physics Uníversity of Helsinki Helsinki Finland Helsinki Institute of Physics Helsinki Finland

A search for exclusive two-photon production via photon exchange in proton-proton collisions, pp → pγγp with intact protons, is presented. The data correspond to an integrated luminosity of 9.4 fb−1 collected in 2016 using the CMS and TOTEM detectors at a center-of-mass energy of 13 TeV at the LHC. Events are selected with a diphoton invariant mass above 350 GeV and with both protons intact in the final state, to reduce backgrounds from strong interactions. The events of interest are those where the invariant mass and rapidity calculated from the momentum losses of the forward-moving protons matches the mass and rapidity of the central, two-photon system. No events are found that satisfy this condition. Interpreting this result in an effective dimension-8 extension of the standard model, the first limits are set on the two anomalous four-photon coupling parameters. If the other parameter is constrained to its standard model value, the limits at 95% CL are |ζ1| -13 GeV−4 and |ζ2| -13 GeV−4 © 2021, CC BY.

关键词： Germanium compounds

来源：评论

学校读者我要写书评

暂无评论

Preparation of logically labeled pure states with only two turns for bulk quantum computation

arXiv

引用

arXiv 2017年

作者： Xin, Tao Hao, Liang Hou, Shi-Yao Feng, Guan-Ru Long, Gui-Lu State Key Laboratory of Low-dimensional Quantum Physics and Department of Physics Tsinghua University Beijing100084 China Tsinghua National Laboratory of Information Science and Technology Beijing100084 China Institute of Applied Physics and Computational Mathematics Beijing100094 China Microsystem and Terahertz Research Center China Academy of Engineering Physics Chengdu610200 China Institute of Electronic Engineering China Academy of Engineering Physics Mianyang621999 China Institute for Quantum Computing WaterlooONN2L 3G1 Canada Department of Physics and Astronomy University of Waterloo WaterlooONN2L 3G1 Canada Innovative Center of Quantum Matter Beijing100084 China

Quantum state preparation plays an equally important role with quantum operations and measurements in quantum information processing. The previous methods of preparing initial state for bulk quantum computation all have inevitable disadvantages, such as, requiring multiple experiments, causing loss of signals, or requiring molecules with restrictive structure. In this work, three kinds of quantum circuits are introduced to prepare the pseudo-pure states of (n − 1) qubits in the Hilbert space of n coupled spins which merely need the assist of one ancilla spin and two experiments independent of n. Being without gradient fields effectively avoids the reduction of the signals. Our methods have no special requirements on the structure of the used molecules. To test these methods more comprehensively, we experimentally demonstrate the preparation of the labeled pseudo-pure states using heteronuclear 2-qubit and homonuclear 4-qubit nuclear magnetic resonance quantum information processor. Copyright © 2017, The Authors. All rights reserved.

关键词： Molecules

来源：评论

学校读者我要写书评

暂无评论

Omnidirectional chargability with directional antennas

Omnidirectional chargability with directional antennas

引用

International Conference on Network Protocols

作者： Haipeng Dai Xiaoyu Wang Alex X. Liu Fengmin Zhang Yang Zhao Guihai Chen State Key Laboratory for Novel Software Technology Nanjing University Nanjing Jiangsu CHINA Department of Computer Science and Engineering Michigan State University East Lansing MI USA Shanghai key Laboratory of Scalable Computing and Systems Shanghai Jiao Tong University Shanghai CHINA

ISBN: (纸本)9781509032822

Wireless Power Transfer (WPT) has received more and more attentions because of its convenience and reliability. In this paper, we first propose the notion of omnidirectional charging by which an area is omnidirectionally charged if a device with directional antennas at any position in the area with any orientation can be charged by directional chargers with power being no smaller than a given threshold. We present our empirical charging model based on field experimental results using off-the-shelf WPT products. Next, we consider the problem of detecting whether the target area achieves omnidirectional charging given a deterministic deployment of chargers. We develop piecewise constant approximation and area discretization techniques to partition the target area into subareas and approximate powers from chargers as constants. Then we propose the Minimum Coverage Set extraction technique which reduces the continuous search space to a discrete one and thereby allows a fast detection algorithm. Moreover, we consider the problem of determining the probability that the target area achieves omnidirectional charging given a random deployment of chargers. We first replace the target area by grid points on triangular lattices to reduce the search space from infinite to finite, then approximate chargers' power with reasonable relaxation, and derive an upper bound of the omnidirectional charging probability. Finally, we conduct both simulation and field experiments, and the results show that our algorithm outperforms comparison algorithms by at least 120%, and the consistency degree of our theoretical results and field experimental results is larger than 93.6%.

关键词： Wireless sensor networks Wireless communication Directional antennas Adaptation models Joining processes Conferences Protocols

来源：评论

学校读者我要写书评

暂无评论

Optimization of integrity measurement algorithm based on multi-thread pipeline paralleling 5

Optimization of integrity measurement algorithm based on mul...

引用

5th International Conference on Computer engineering and Networks, CENet 2015

作者： Wang, Yinhao Shan, Zheng Fan, Chao Xue, Fei State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou Henan450002 China

With the continuous development of trusted computing, the integrity measurement has gradually been practical;but the popularization and application of the existing measurement tools are still restricted by their own measurement algorithm's performance. Considering the insufficient of existing measurement tools' performance, we propose an optimization method of integrity measurement algorithm based on multi-thread and pipeline paralleling. We analyze shortage of the existing measurement tools and provide an optimized method based on multi-thread technology and pipeline paralleling technology. Experiments show that this method can significantly improve the performance of SHA-1 and is also applicable to a variety of hash algorithms. © Copyright owned by the author(s) under the terms of the Creative Commons.

关键词： Pipelines

来源：评论

学校读者我要写书评

暂无评论

Constraints on dark photon dark matter using data from LIGO’s and Virgo’s third observing run

引用

Physical Review D 2022年第6期105卷 063030-063030页

作者： R. Abbott T. D. Abbott F. Acernese K. Ackley C. Adams N. Adhikari R. X. Adhikari V. B. Adya C. Affeldt D. Agarwal M. Agathos K. Agatsuma N. Aggarwal O. D. Aguiar L. Aiello A. Ain P. Ajith T. Akutsu S. Albanesi A. Allocca P. A. Altin A. Amato C. Anand S. Anand A. Ananyeva S. B. Anderson W. G. Anderson M. Ando T. Andrade N. Andres T. Andrić S. V. Angelova S. Ansoldi J. M. Antelis S. Antier S. Appert Koji Arai Koya Arai Y. Arai S. Araki A. Araya M. C. Araya J. S. Areeda M. Arène N. Aritomi N. Arnaud S. M. Aronson K. G. Arun H. Asada Y. Asali G. Ashton Y. Aso M. Assiduo S. M. Aston P. Astone F. Aubin C. Austin S. Babak F. Badaracco M. K. M. Bader C. Badger S. Bae Y. Bae A. M. Baer S. Bagnasco Y. Bai L. Baiotti J. Baird R. Bajpai M. Ball G. Ballardin S. W. Ballmer A. Balsamo G. Baltus S. Banagiri D. Bankar J. C. Barayoga C. Barbieri B. C. Barish D. Barker P. Barneo F. Barone B. Barr L. Barsotti M. Barsuglia D. Barta J. Bartlett M. A. Barton I. Bartos R. Bassiri A. Basti M. Bawaj J. C. Bayley A. C. Baylor M. Bazzan B. Bécsy V. M. Bedakihale M. Bejger I. Belahcene V. Benedetto D. Beniwal T. F. Bennett J. D. Bentley M. BenYaala F. Bergamin B. K. Berger S. Bernuzzi D. Bersanetti A. Bertolini J. Betzwieser D. Beveridge R. Bhandare U. Bhardwaj D. Bhattacharjee S. Bhaumik I. A. Bilenko G. Billingsley S. Bini R. Birney O. Birnholtz S. Biscans M. Bischi S. Biscoveanu A. Bisht B. Biswas M. Bitossi M.-A. Bizouard J. K. Blackburn C. D. Blair D. G. Blair R. M. Blair F. Bobba N. Bode M. Boer G. Bogaert M. Boldrini L. D. Bonavena F. Bondu E. Bonilla R. Bonnand P. Booker B. A. Boom R. Bork V. Boschi N. Bose S. Bose V. Bossilkov V. Boudart Y. Bouffanais A. Bozzi C. Bradaschia P. R. Brady A. Bramley A. Branch M. Branchesi J. E. Brau M. Breschi T. Briant J. H. Briggs A. Brillet M. Brinkmann P. Brockill A. F. Brooks J. Brooks D. D. Brown S. Brunett G. Bruno R. Bruntz J. Bryant T. Bulik H. J. Bulten A. Buonanno R. Buscicchio D. Buskulic C. Buy R. L. Byer L. Cadonati G. Cagnoli C. Cahillane J. Calderón Bustillo J. D. Callaghan T. A. Callis LIGO Laboratory California Institute of Technology Pasadena California 91125 USA Louisiana State University Baton Rouge Louisiana 70803 USA Dipartimento di Farmacia Università di Salerno I-84084 Fisciano Salerno Italy INFN Sezione di Napoli Complesso Universitario di Monte S. Angelo I-80126 Napoli Italy OzGrav School of Physics and Astronomy Monash University Clayton 3800 Victoria Australia LIGO Livingston Observatory Livingston Louisiana 70754 USA University of Wisconsin-Milwaukee Milwaukee Wisconsin 53201 USA OzGrav Australian National University Canberra Australian Capital Territory 0200 Australia Max Planck Institute for Gravitational Physics (Albert Einstein Institute) D-30167 Hannover Germany Leibniz Universität Hannover D-30167 Hannover Germany Inter-University Centre for Astronomy and Astrophysics Pune 411007 India University of Cambridge Cambridge CB2 1TN United Kingdom Theoretisch-Physikalisches Institut Friedrich-Schiller-Universität Jena D-07743 Jena Germany University of Birmingham Birmingham B15 2TT United Kingdom Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) Northwestern University Evanston Illinois 60208 USA Instituto Nacional de Pesquisas Espaciais 12227-010 São José dos Campos São Paulo Brazil Gravity Exploration Institute Cardiff University Cardiff CF24 3AA United Kingdom INFN Sezione di Pisa I-56127 Pisa Italy International Centre for Theoretical Sciences Tata Institute of Fundamental Research Bengaluru 560089 India Gravitational Wave Science Project National Astronomical Observatory of Japan (NAOJ) Mitaka City Tokyo 181-8588 Japan Advanced Technology Center National Astronomical Observatory of Japan (NAOJ) Mitaka City Tokyo 181-8588 Japan INFN Sezione di Torino I-10125 Torino Italy Università di Napoli “Federico II” Complesso Universitario di Monte S. Angelo I-80126 Napoli Italy Université de Lyon Université Claude Bernard Lyon 1 CNRS Institut Lumière Matière F-69622 Villeurbanne Franc

We present a search for dark photon dark matter that could couple to gravitational-wave interferometers using data from Advanced LIGO and Virgo’s third observing run. To perform this analysis, we use two methods, one based on cross-correlation of the strain channels in the two nearly aligned LIGO detectors, and one that looks for excess power in the strain channels of the LIGO and Virgo detectors. The excess power method optimizes the Fourier transform coherence time as a function of frequency, to account for the expected signal width due to Doppler modulations. We do not find any evidence of dark photon dark matter with a mass between mA∼10−14–10−11 eV/c2, which corresponds to frequencies between 10–2000 Hz, and therefore provide upper limits on the square of the minimum coupling of dark photons to baryons, i.e., U(1)B dark matter. For the cross-correlation method, the best median constraint on the squared coupling is ∼1.31×10−47 at mA∼4.2×10−13 eV/c2; for the other analysis, the best constraint is ∼2.4×10−47 at mA∼5.7×10−13 eV/c2. These limits improve upon those obtained in direct dark matter detection experiments by a factor of ∼100 for mA∼[2–4]×10−13 eV/c2, and are, in absolute terms, the most stringent constraint so far in a large mass range mA∼2×10−13–8×10−12 eV/c2.

关键词： Dark matter Gravitational wave detectors

来源：评论

学校读者我要写书评

暂无评论

Simulations of fractal star cluster formation: I. new insights for measuring mass segregation of star clusters with substructure

arXiv

引用

arXiv 2017年

作者： Yu, Jincheng Puzia, Thomas H. Lin, Congping Zhang, Yiwei Institute of Astrophysics Pontificia Universidad Católica de Chile Av. Vicuna Mackenna 4860 Macul Santiago7820436 National Astronomical Observatories Chinese Academy of Sciences 20A Datun Road Beijing100012 Center for Mathematical Science Huazhong University of Science and Technology 1037 Luoyu Road Wuhan4370074 Hubei Key Laboratory of Engineering Modeling and Scientific Computing Huazhong University of Science and Technology 1037 Luoyu road Wuhan430074 School of Mathematics and Statistics Huazhong University of Science and Technology 1037 Luoyu Road Wuhan4370074

We compare the existent methods including the minimum spanning tree based method and the local stellar density based method, in measuring mass segregation of star clusters. We find that the minimum spanning tree method reflects more the compactness, which represents the global spatial distribution of massive stars, while the local stellar density method reflects more the crowdedness, which provides the local gravitational potential information. It is suggested to measure the local and the global mass segregation simultaneously. We also develop a hybrid method that takes both aspects into account. This hybrid method balances the local and the global mass segregation in the sense that the predominant one is either caused either by dynamical evolution or purely accidental, especially when such information is unknown a priori. In addition, we test our prescriptions with numerical models and show the impact of binaries in estimating the mass segregation value. As an application, we use these methods on the Orion Nebula Cluster (ONC) observations and the Taurus cluster. We find that the ONC is significantly mass segregated down to the 20th most massive stars. In contrast, the massive stars of the Taurus cluster are sparsely distributed in many different subclusters, showing a low degree of compactness. The massive stars of Taurus are also found to be distributed in the high-density region of the subclusters, showing significant mass segregation at subcluster scales. Meanwhile, we also apply these methods to discuss the possible mechanisms of the dynamical evolution of the simulated substructured star clusters. Copyright © 2017, The Authors. All rights reserved.

关键词： Numerical methods

来源：评论

学校读者我要写书评

暂无评论

Reducing DRAM refreshing in an error correction manner

引用

Science China Chemistry 2015年第12期58卷 186-199页

作者： ZHU DanFeng WANG Rui WEI YanJiang QIAN DePei School of Computer Science and Engineering Beihang University State Key Laboratory of Mathematical Engineering and Advanced Computing

Dynamic random access memory(DRAM) is facing the challenge of technology scaling. The decreasing feature size makes it harder to make DRAM cells which can keep the current data-holding time. When DRAM cells cannot hold data for a long time, DRAM chips need a more frequent refreshing operation. Therefore, in the near future, time and energy cost on DRAM refreshing will be no longer trivial. In this paper, we propose DRAM Error Correction Pointer(ECP), an error-correction-manner framework, to reduce DRAM refreshes without data loss. We exploit the non-uniform feature of DRAM cells with respect to the data retention time. Compared with the conventional refreshing mechanisms, which refresh DRAM chips by the retention time of the leakiest cells, we refresh the chips much fewer times, and treat the not-in-time refreshed cells as fault elements. We use the structure of ECP as a fault tolerant element. By recording the data which are supposed to be written into the leaky cells in our DRAM-ECP structures, DRAM-ECP can significantly decrease refreshing frequency. When these data are to be read out, DRAM-ECP retrieves the data stored in ECPs and covers them to the corresponding position in the data row. Our experiments show that DRAM-ECP can reduce over 70%refreshing operations than the current refreshing mechanism and also get significant energy saving.

关键词： DRAM refreshing error correction DRAM-ECP counting bloom filter retention time

来源：评论

学校读者我要写书评

暂无评论

A improved sequential pattern mining algorithm based on PrefixSpan

A improved sequential pattern mining algorithm based on Pref...

引用

Proceedings of the Biannual World Automation Congress

作者： Xue Fei Shan Zheng Li-jing Yan Chao Fan State Key Laboratory of Mathematical Engineering and Advanced Computing China Line Adv. Comput. Zhengzhou Sci. & Technol. Inst. Zhengzhou China

In order to solve the problem of large space and time overhead in the PrefixSpan algorithm, a new sequential pattern mining algorithm based on PrefixSpan is proposed, which is PrefixSpan-x algorithm. The algorithm reduces unnecessary storage space and removes the non-frequent items, and combines AC automaton to optimize frequent sub-sequence mining, so as to improve the performance. Experiments prove that the performance of PrefixSpan-x algorithm is better than Prefixspan algorithm in time and space.

关键词： Databases Algorithm design and analysis Data mining Automata Classification algorithms Fans Pattern matching

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：