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Secrecy analysis of full-duplex power-splitting SWIPT networks with artificial noise 7

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Secrecy analysis of full-duplex power-splitting SWIPT networ...

2017 7th International Workshop on Computer science and Engineering, WCSE 2017

作者： Tang, Xuanxuan Yang, Wendong Cai, Yueming Yang, Weiwei Cao, Kuo Yuan, Pan College of Communications Engineering PLA University of Science and Technology Nanjing China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Post and Telecommunications Ministry of Education China

ISBN: (纸本)9789811136719

This work conducts the secrecy analysis of full-duplex power-splitting simultaneous wireless information and power transfer networks with artificial noise. The exact closed-form expressions of the COP, SOP and RSP are derived, respectively, which are illustrated by numerical analysis. The results depict the significance of the power-splitting ratio and the transmit signal-to-noise ratio (SNR). To be specific, the secrecy performance is greatly improved with the increasing of the power-splitting ratio. In addition, it is observed that the security of the system will get enhanced with the increasing of the power-splitting ratio at first and then get reversed for a certain transmit SNR. Moreover, the value of the optimum transmit SNR changes with different transmit SNR.

关键词： Signal to noise ratio

WVCC: Weighted virtual congestion control for datacenter networks

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WVCC: Weighted virtual congestion control for datacenter net...

ACM SIGCOMM 2017 Conference

作者： Dong, Jiaqing Wang, Yi Tian, Chen Jin, Bo Yin, Hao Zhang, Gong Department of Computer Science Tsinghua University China Future Network Theory Lab Huawei China State Key Laboratory for Novel Software Technology Nanjing University China

ISBN: (纸本)9781450350570

Enforcing virtualized congestion control is a new trend for datacenter networks. Virtual Congestion Control (VCC) can also enforce differentiated Quality-of-Service (QoS) for flows. However, current flow differentiation algorithms only provide qualitative rather than quantitative bandwidth allocation. Weighted bandwidth allocation is critical to enforce administrator policy. In this work, we propose Weighted Virtual Congestion Control (WVCC) enforcement for datacenter networks. It is a novel per-flow differentiation mechanism capable of proportionally allocating bandwidth among flows. © 2017 ACM.

关键词： Virtualization

SEARCH FOR EXTENDED GEV SOURCES IN THE INNER GALACTIC PLANE

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arXiv 2024年

作者： Abdollahi, S. Acero, F. Acharyya, A. Adelfio, A. Ajello, M. Baldini, L. Ballet, J. Bartolini, C. Gonzalez, J. Becerra Bellazzini, R. Bissaldi, E. Bonino, R. Bruel, P. Cameron, R.A. Caraveo, P.A. Castro, D. Cavazzuti, E. Cheung, C.C. Cibrario, N. Ciprini, S. Cozzolongo, G. Orestano, P. Cristarella Cuoco, A. Cutini, S. D’Ammando, F. Di Lalla, N. Dinesh, A. Di Venere, L. Domínguez, A. Fiori, A. Funk, S. Fusco, P. Gargano, F. Gasbarra, C. Gasparrini, D. Germani, S. Giacchino, F. Giglietto, N. Giliberti, M. Giordano, F. Giroletti, M. Green, D. Grenier, I.A. Guillemot, L. Guiriec, S. Gupta, R. Hashizume, M. Hays, E. Hewitt, J.W. Horan, D. Hou, X. Kayanoki, T. Kuss, M. Laviron, A. Lemoine-Goumard, M. Liguori, A. Li, J. Liodakis, I. Loizzo, P. Longo, F. Loparco, F. Lorusso, L. Lovellette, M.N. Lubrano, P. Maldera, S. Malyshev, D. Martí-Devesa, G. Martin, P. Mazziotta, M.N. Mereu, I. Michelson, P.F. Mirabal, N. Mitthumsiri, W. Mizuno, T. Monti-Guarnieri, P. Monzani, M.E. Morselli, A. Moskalenko, I.V. Negro, M. Omodei, N. Orienti, M. Orlando, E. Paneque, D. Panzarini, G. Persic, M. Pesce-Rollins, M. Pillera, R. Porter, T.A. Rainò, S. Rando, R. Razzano, M. Reimer, A. Reimer, O. Bernal, M. Rocamora Sánchez-Conde, M. Parkinson, P.M. Saz Serini, D. Sgrò, C. Siskind, E.J. Smith, D.A. Spandre, G. Spinelli, P. Strong, A.W. Suson, D.J. Tajima, H. Thayer, J.B. Torres, D.F. Valverde, J. Wadiasingh, Z. Wood, K. Zaharijas, G. IRAP Université de Toulouse CNRS UPS CNES ToulouseF-31028 France AIM CEA CNRS Université Paris-Saclay Université de Paris Gif-sur-YvetteF-91191 France Center for Cosmology and Particle Physics Phenomenology University of Southern Denmark Campusvej 55 Odense MDK-5230 Denmark Istituto Nazionale di Fisica Nucleare Sezione di Perugia PerugiaI-06123 Italy Department of Physics and Astronomy Clemson University Kinard Lab of Physics ClemsonSC29634-0978 United States Università di Pisa Istituto Nazionale di Fisica Nucleare Sezione di Pisa PisaI-56127 Italy Université Paris-Saclay Université Paris Cité CEA CNRS AIM Gif-sur-YvetteF-91191 Cedex France Istituto Nazionale di Fisica Nucleare Sezione di Bari BariI-70126 Italy Università degli studi di Trento via Calepina 14 Trento38122 Italy Instituto de Astrofísica de Canarias Universidad de La Laguna Dpto. Astrofísica Tenerife La Laguna38200 Spain Istituto Nazionale di Fisica Nucleare Sezione di Pisa PisaI-56127 Italy Dipartimento di Fisica "M. Merlin" dell’Università e del Politecnico di Bari via Amendola 173 BariI-70126 Italy Istituto Nazionale di Fisica Nucleare Sezione di Torino TorinoI-10125 Italy Dipartimento di Fisica Università degli Studi di Torino TorinoI-10125 Italy Laboratoire Leprince-Ringuet CNRS IN2P3 École polytechnique Institut Polytechnique de Paris Palaiseau91120 France W. W. Hansen Experimental Physics Laboratory Kavli Institute for Particle Astrophysics and Cosmology Department of Physics SLAC National Accelerator Laboratory Stanford University StanfordCA94305 United States INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica Milano via E. Bassini 15 MilanoI-20133 Italy Harvard-Smithsonian Center for Astrophysics CambridgeMA02138 United States Astrophysics Science Division NASA Goddard Space Flight Center GreenbeltMD20771 United States Italian Space Agency Via del Politecnico snc Roma00133 Italy Space Science Division Naval Research Laboratory Washin

The recent detection of extended γ-ray emission around middle-aged pulsars is interpreted as inverse-Compton scattering of ambient photons by electron-positron pairs escaping the pulsar wind nebula, which are confined near the system by unclear mechanisms. This emerging population of γ-ray sources was first discovered at TeV energies and remains underexplored in the GeV range. To address this, we conducted a systematic search for extended sources along the Galactic plane using 14 years of Fermi-LAT data above 10 GeV, aiming to identify a number of pulsar halo candidates and extend our view to lower energies. The search covered the inner Galactic plane (|l| ≤ 100◦, |b| ≤ 1◦) and the positions of known TeV sources and bright pulsars, yielding broader astrophysical interest. We found 40 such sources, forming the Second Fermi Galactic Extended Sources Catalog (2FGES), most with 68% containment radii smaller than 1.0◦ and relatively hard spectra with photon indices below 2.5. We assessed detection robustness using field-specific alternative interstellar emission models and by inspecting significance maps. Noting 13 sources previously known as extended in the 4FGL-DR3 catalog and five dubious sources from complex regions, we report 22 newly detected extended sources above 10 GeV. Of these, 13 coincide with H.E.S.S., HAWC, or LHAASO sources;six coincide with bright pulsars (including four also coincident with TeV sources);six are associated with 4FGL point sources only;and one has no association in the scanned catalogs. Notably, six to eight sources may be related to pulsars as classical pulsar wind nebulae or pulsar halos. © 2024, CC BY.

关键词： Gamma rays

JWST Discovery of Dust Reservoirs in Nearby Type IIP Supernovae 2004et and 2017eaw

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arXiv 2023年

作者： Shahbandeh, Melissa Sarangi, Arkaprabha Temim, Tea Szalai, Tamás Fox, Ori D. Tinyanont, Samaporn Dwek, Eli Dessart, Luc Filippenko, Alexei V. Brink, Thomas G. Foley, Ryan J. Jencson, Jacob Pierel, Justin Zsíros, Szanna Rest, Armin Zheng, WeiKang Andrews, Jennifer Clayton, Geoffrey C. De, Kishalay Engesser, Michael Gezari, Suvi Gomez, Sebastian Gonzaga, Shireen Johansson, Joel Kasliwal, Mansi Lau, Ryan De Looze, Ilse Marston, Anthony Milisavljevic, Dan O'Steen, Richard Siebert, Matthew Skrutskie, Michael Smith, Nathan Strolger, Lou Van Dyk, Schuyler D. Wang, Qinan Williams, Brian Williams, Robert Xiao, Lin Department of Physics and Astronomy Johns Hopkins University BaltimoreMD21218 United States Space Telescope Science Institute 3700 San Martin Drive BaltimoreMD21218 United States DARK Niels Bohr Institute University of Copenhagen Jagtvej 128 Copenhagen2200 Denmark Department of Astrophysical Sciences Princeton University PrincetonNJ08544 United States Department of Experimental Physics Institute of Physics University of Szeged Dóm tér 9 SzegedH-6720 Hungary ELKH SZTE Stellar Astrophysics Research Group Szegedi út Kt. 766 BajaH-6500 Hungary Department of Astronomy and Astrophysics University of California Santa CruzCA95064 United States Observational Cosmology Lab NASA Goddard Space Flight Center Code 665 GreenbeltMD20771 United States Institut d'Astrophysique de Paris CNRS Sorbonne Université 98 bis boulevard Arago ParisF-75014 France Department of Astronomy University of California BerkeleyCA94720-3411 United States Gemini Observatory 670 N. Aohoku Place HiloHI96720 United States Department of Physics & Astronomy Louisiana State University Baton RougeLA70803 United States MIT-Kavli Institute for Astrophysics and Space Research 77 Massachusetts Ave. CambridgeMA02139 United States Department of Physics The Oskar Klein Center Stockholm University AlbaNova Stockholm10691 Sweden Cahill Center for Astrophysics California Institute of Technology 1200 E. California Blvd PasadenaCA91125 United States NSF's NOIRLab 950 N. Cherry Avenue TucsonAZ85719 United States Sterrenkundig Observatorium Ghent University Krijgslaan 281 - S9 Gent9000 Belgium ESAC Villanueva de la Canada Madrid28692 Spain Purdue University Department of Physics and Astronomy 525 Northwestern Ave West LafayetteIN4790720 United States Integrative Data Science Initiative Purdue University West LafayetteIN47907 United States Department of Astronomy University of Virginia CharlottesvilleVA22904-4325 United States Steward Observatory University o

Supernova (SN) explosions have been sought for decades as a possible source of dust in the Universe, providing the seeds of galaxies, stars, and planetary systems. SN 1987A offers one of the most promising examples of significant SN dust formation, but until the James Webb Space Telescope (JWST), instruments have traditionally lacked the sensitivity at both late times (> 1 yr post-explosion) and longer wavelengths (i.e., > 10 μm) to detect analogous dust reservoirs. Here we present JWST/MIRI observations of two historic Type IIP SNe, 2004et and SN 2017eaw, at nearly 18 yr and 5 yr post-explosion, respectively. We fit the spectral energy distributions as functions of dust mass and temperature, from which we are able to constrain the dust geometry, origin, and heating mechanism. We place a 90% confidence lower limit on the dust masses for SNe 2004et and 2017eaw of > 0.014 and > 4 × 10−4 M, respectively. More dust may exist at even colder temperatures or may be obscured by high optical depths. We conclude dust formation in the ejecta to be the most plausible and consistent scenario. The observed dust is radiatively heated to ∼ 100-150 K by ongoing shock interaction with the circumstellar medium. Regardless of the best fit or heating mechanism adopted, the inferred dust mass for SN 2004et is the second highest (next to SN 1987A) inferred dust mass in extragalactic SNe thus far, promoting the prospect of SNe as potential significant sources of dust in the Universe. © 2023, CC BY.

关键词： Dust

An -norm Based Method for Off-grid DOA Estimation

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Circuits, Systems, and Signal Processing 2018年第2期38卷 904-917页

作者： Zhang, Zeyun Wu, Xiaohuan Li, Chunguo Zhu, Wei-Ping The Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing People’s Republic of China School of Information Science and Engineering Southeast University Nanjing People’s Republic of China Department of Electrical and Computer Engineering Concordia University Montreal Canada

The sparse signal recovery-based direction of arrival (DOA) estimation has received a great deal of attention over the past decade. From the sparse representation point of view, $$\ell _0$$ -norm is the best choice to evaluate the sparsity of a vector. However, solving an $$\ell _0$$ -norm minimization problem is non-deterministic polynomial hard (NP-hard). Thus, The common idea for many sparse DOA estimation methods is to use the $$\ell _1$$ -norm as the sparsity metric. However, its sparse solution may not coincide with the solution resulting from the $$\ell _0$$ -norm thus deteriorating the DOA estimation performance. In this paper, we propose a new sparse method based on $$\ell _p$$ ( $$0<1$$ ) regularization for DOA estimation to achieve a sparser solution than $$\ell _1$$ regularization. In particular, we use the Taylor expansion to convert the $$\ell _p$$ -norm minimization problem to a weighted $$\ell _1$$ -norm problem. Then, a two-step iterative method is employed to achieve the DOA estimate. The $$\ell _p$$ ( $$0<1$$ ) regularization is able to improve the angle resolution, leading to an improved performance in low SNR and correlated signal scenarios. Numerical results show that our proposed method has better estimation performance than many other methods do.

关键词：

Social cognitive optimization with tent map for combined heat and power economic dispatch

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arXiv 2018年

作者： Sun, Jiaze Li, Yang School of Computer Science and Technology Xi 'an University of Posts and Telecommunications Xi'an710121 China Shaanxi Key Laboratory of Network Data Intelligent Processing Xi 'an University of Posts and Telecommunications Xi 'an710121 China School of Electrical Engineering Northeast Electric Power University Jilin132012 China

Combined Heat and Power Economic Dispatch (CHPED) problem is a sophisticated constrained nonlinear optimization problem in a heat and power production system for assigning heat and power production to minimize the production costs. To address this challenging problem, a novel Social Cognitive Optimization algorithm with Tent map (TSCO) is presented for solving the CHPED problem. To handle the equality constraints in heat and power balance constraints, Adaptive Constraints Relaxing (ACR) rule is adopted in constraint processing. The novelty of our work lies in the introduction of a new powerful TSCO algorithm to solve the CHPED issue. The effectiveness and superiority of the presented algorithm is validated by carrying out two typical CHPED cases. The numerical results show that the proposed approach has better convergence speed and solution quality than all other existing state-of-the-art algorithms. Copyright © 2018, The Authors. All rights reserved.

关键词： Functions

Top-N-Rank: A Scalable List-wise Ranking Method for Recommender Systems

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arXiv 2018年

作者： Liang, Junjie Hu, Jinlong Dong, Shoubin Honavar, Vasant Artificial Intelligence Research Laboratory Center for Big Data Analytics and Discovery Informatics College of Information Sciences and Technology Pennsylvania State University University ParkPA16802 United States Guangdong Key Laboratory of Communication & Computer Network School of Computer Science and Engineering South China University of Technology Guangzhou510006 China

We propose Top-N-Rank, a novel family of list wise Learning-to-Rank models for reliably recommending the N top-ranked items. The proposed models optimize a variant of the widely used discounted cumulative gain (DCG) objective function which differs from DCG in two important aspects: (i) It limits the evaluation of DCG only on the top N items in the ranked lists, thereby eliminating the impact of low-ranked items on the learned ranking function;and (ii) it incorporates weights that allow the model to leverage multiple types of implicit feedback with differing levels of reliability or trustworthiness. Because the resulting objective function is non-smooth and hence challenging to optimize, we consider two smooth approximations of the objective function, using the traditional sigmoid function and the rectified linear unit (ReLU). We propose a family of learning-to-rank algorithms (Top-N-Rank) that work with any smooth objective function. Then, a more efficient variant, ***, is introduced, which effectively exploits the properties of ReLU function to reduce the computational complexity of Top-N-Rank from quadratic to linear in the average number of items rated by users. The results of our experiments using two widely used benchmarks, namely, the MovieLens data set and the Amazon Video Games data set demonstrate that: (i) The "top-N truncation" of the objective function substantially improves the ranking quality of the top N recommendations;(ii) using the ReLU for smoothing the objective function yields significant improvement in both ranking quality as well as runtime as compared to using the sigmoid;and (iii) *** substantially outperforms the well-performing list-wise ranking methods in terms of ranking quality. Copyright © 2018, The Authors. All rights reserved.

关键词： Benchmarking

Automatic Chinese Multiple-Choice Question Generation for Human Resource Performance Appraisal

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Procedia Computer science 2018年 139卷 165-172页

作者： Pei Quan Yong Shi Lingfeng Niu Ying Liu Tianlin Zhang School of Computer and Control Engineering University of Academy of Sciences Beijing 100190 China School of Economics and Management University of Chinese Academy of Sciences Beijing 100190 China Key Lab of Big Data Mining and Knowledge Management Chinese Academy of Sciences Beijing 100190 China Research Center on Fictitious Economy and Data Science Chinese Academy of Sciences Beijing 100190 China College of Information Science and Technology University of Nebraska at Omaha NE 68182 USA

Performance appraisal has always been an important research topic in human resource management. A reasonable performance appraisal plan lays a solid foundation for the development of an enterprise. Especially as globalization and technology advance, in order to meet the fast-changing strategic goals and increasing cross-functional tasks, enterprises face new challenges in performance appraisal. How to improve employees’ ability to accept new knowledge efficiently and constantly has been an urgent problem for enterprises. In this paper, we propose an automatic method which generation multiple-choice questions by utilizing the relations between different terminology. Graphical model is used to extract core concept from different corpus while word embedding technology is used to indicate the relevant relations. Experimental results demonstrate that the proposed question generation method outperforms the traditional manual method in both efficiency and confusion.

关键词： Human resource management multiple-choice question generation natural language processing word embedding

Angle-domain approach for parameter estimation in high-mobility OFDM with fully/partly calibrated massive ULA

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arXiv 2018年

作者： Ge, Yinghao Zhang, Weile Gao, Feifei Minn, Hlaing MOE Key Lab for Intelligent Networks and Network Security Xi'an Jiaotong University Xi'an Shaanxi710049 China State Key Laboratory of Intelligent Technology and Systems Tsinghua National Laboratory for Information Science and Technology Department of Automation Tsinghua University Beijing100084 China Department of Electrical Engineering University of Texas Dallas United States

In this paper, we consider a downlink orthogonal frequency division multiplexing (OFDM) system from a base station to a high-speed train (HST) equipped with fully/partly calibrated massive uniform linear antenna-array (ULA) in wireless environments with abundant scatterers. Multiple Doppler frequency offsets (DFOs) stemming from intensive propagation paths together with transceiver oscillator frequency offset (OFO) result in a fast time-varying frequency-selective channel. We develop an angle domain carrier frequency offset (CFO, general designation for DFO and OFO) estimation approach. A high-resolution beamforming network is designed to separate different DFOs into a set of parallel branches in angle domain such that each branch is mainly affected by a single dominant DFO. Then, a joint estimation algorithm for both maximum DFO and OFO is developed for fully calibrated ULA. Next, its estimation mean square error (MSE) performance is analyzed under inter-subarray mismatches. To mitigate the detrimental effects of inter-subarray mismatches, we introduce a calibration-oriented beamforming parameter (COBP) and develop the corresponding modified joint estimation algorithm for partly calibrated ULA. Moreover, the Cramér-Rao lower bound of CFO estimation is derived. Both theoretical and numerical results are provided to corroborate the proposed method. Copyright © 2018, The Authors. All rights reserved.

关键词： Calibration