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Performance of resource allocation in device-to-device communication systems based on particle swarm optimization

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Performance of resource allocation in device-to-device commu...

2017 IEEE International Conference on Systems, Man, and Cybernetics, SMC 2017

作者： Huang, Yung-Fa Tan, Tan-Hsu Liu, Shing-Hong Chen, Yung-Fu Department of Information and Communication Engineering Chaoyang University of Technology Taichung Taiwan Bor-An Chen Department of Electrical Engineering National Taipei University of Technology Taipei Taiwan Department of Computer Science and Information Engineering Chaoyang University of Technology Taichung Taiwan Department of Dental Technology and Materials Science Central Taiwan University of Science and Technology Taichung Taiwan

ISBN: (纸本)9781538616451

In this study, the resource blocks (RB) are allocated to user equipment (UE) according to the evolutional algorithms for long term evolution (LTE) systems. Particle Swarm Optimization (PSO) algorithm is one of the evolutionary algorithms, based on the imitation of a flock of birds foraging behavior through learning and grouping the best experience. Therefore, we propose a Simple Particle Swarm Optimization (SPSO) algorithm for RB allocation to enhance the throughput of Device-to-Device (D2D) communications and improve the system capacity performance. The simulation results show that with less population size of M=10, the SPSO can perform quickly convergence to sub-optimal solution in the 100th generation. Therefore, as compared to the random allocation (Rand) method, the proposed SPSO can obtain sub-optimum performance with more 2 UEs than the Rand method. © 2017 IEEE.

关键词： Resource allocation

Superconductivity of platinum hydride

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arXiv 2018年

作者： Matsuoka, Takahiro Hishida, Masahiro Kuno, Keiji Hirao, Naohisa Ohishi, Yasuo Sasaki, Shigeo Takahama, Kazushi Shimizu, Katsuya Department of Electrical Electronic and Computer Engineering Gifu University Gifu Japan Department of Materials Science and Technology Gifu University Gifu Japan Environmental and Renewable Energy Systems Division Gifu University Gifu Japan Japan Synchrotron Radiation Research Institute Hyogo Japan Center for Science and Technology under Extreme Conditions Graduate School of Engineering Science Osaka University Japan

We report the ac magnetic susceptibility, electrical resistance, and X-ray diffraction measurements of platinum hydride (PtHx) in diamond anvil cells, which reveal its superconducting transition. At 32 GPa, when PtHx is in a P63/mmc structure, PtHx exhibits superconducting transition at 6.7 K and superconducting transition temperature (Tc) decreases with pressure to 4.8 K at 36 GPa. The observed Tc is higher than that of powdered Pt by more than three orders of magnitude. It is suggested that hydrides of noble metals have higher Tc than the elements. Copyright © 2018, The Authors. All rights reserved.

关键词： Superconducting transition temperature

A polarization-induced 2D hole gas in undoped gallium nitride quantum wells

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arXiv 2018年

作者： Chaudhuri, Reet Bader, Samuel James Chen, Zhen Muller, David A. Xing, Huili Grace Jena, Debdeep School of Electrical and Computer Engineering Cornell University IthacaNY14853 United States School of Applied and Engineering Physics Cornell University IthacaNY14853 United States Department of Materials Science and Engineering Cornell University IthacaNY14853 United States Kavli Institute at Cornell for Nanoscale Science Cornell University IthacaNY14853

The long-missing polarization-induced two-dimensional hole gas is finally observed in undoped gallium nitride quantum wells. Experimental results provide unambiguous proof that a 2D hole gas in GaN grown on AlN does not need acceptor doping, and can be formed entirely by the difference in the internal polarization fields across the semiconductor heterojunction. The measured 2D hole gas densities, about 4 1013 cm-2, are among the highest among all known semiconductors and remain unchanged down to cryogenic temperatures. Some of the lowest sheet resistances of all wide-bandgap semiconductors are seen. The observed results provide a new probe for studying the valence band structure and transport properties of wide-bandgap nitride interfaces, and simultaneously enable the missing component for gallium nitride-based p-channel transistors for energy-efficient electronics. Copyright © 2018, The Authors. All rights reserved.

关键词： III-V semiconductors

Extreme broadband transparent optical phase change materials for high-performance nonvolatile photonics

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arXiv 2018年

作者： Zhang, Yifei Chou, Jeffrey B. Li, Junying Li, Huashan Du, Qingyang Yadav, Anupama Zhou, Si Shalaginov, Mikhail Y. Fang, Zhuoran Zhong, Huikai Roberts, Christopher Robinson, Paul Bohlin, Bridget Ríos, Carlos Lin, Hongtao Kang, Myungkoo Gu, Tian Warner, Jamie Liberman, Vladimir Richardson, Kathleen Hu, Juejun Department of Materials Science & Engineering Massachusetts Institute of Technology CambridgeMA United States Lincoln Laboratory Massachusetts Institute of Technology LexingtonMA United States Shanghai Key Laboratory of Modern Optical Systems College of Optical-Electrical and Computer Engineering University of Shanghai for Science and Technology Shanghai China Sino-French Institute for Nuclear Energy and Technology Sun Yat-sen University Guangzhou China College of Optics & Photonics Department of Materials Science and Engineering University of Central Florida Orlando United States Department of Materials University of Oxford Oxford United Kingdom College of Information Science & Electronic Engineering Zhejiang University Hangzhou China

Optical phase change materials (O-PCMs), a unique group of materials featuring drastic optical property contrast upon solid-state phase transition, have found widespread adoption in photonic switches and routers, reconfigurable meta-optics, reflective display, and optical neuromorphic computers. Current phase change materials, such as Ge-Sb-Te (GST), exhibit large contrast of both refractive index (∆n) and optical loss (∆k), simultaneously. The coupling of both optical properties fundamentally limits the function and performance of many potential applications. In this article, we introduce a new class of O-PCMs, Ge-Sb-Se-Te (GSST) which breaks this traditional coupling, as demonstrated with an optical figure of merit improvement of more than two orders of magnitude. The first-principle computationally optimized alloy, Ge2Sb2Se4Te1, combines broadband low loss (1 – 18.5 μm), large optical contrast (∆n = 2.0), and significantly improved glass forming ability, enabling an entirely new field of infrared and thermal photonic devices. We further leverage the material to demonstrate nonvolatile integrated optical switches with record low loss and large contrast ratio, as well as an electrically addressed, microsecond switched pixel level spatial light modulator, thereby validating its promise as a platform material for scalable nonvolatile photonics. Copyright © 2018, The Authors. All rights reserved.

关键词： Phase change materials

Blue (In,Ga)N Light-Emitting Diodes with Buried n+-p+ Tunnel Junctions by Plasma-Assisted Molecular Beam Epitaxy

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arXiv 2018年

作者： Cho, YongJin Bharadwaj, Shyam Hu, Zongyang Nomoto, Kazuki Jahn, Uwe Xing, Huili Grace Jena, Debdeep School of Electrical and Computer Engineering Cornell University IthacaNY14853 United States Paul-Drude-Institut für Festkörkperelektronik Hausvogteiplatz 5–7 Berlin10117 Germany Department of Materials Science and Engineering Kavli Institute for Nanoscale Science Cornell University IthacaNY14853 United States

Blue light-emitting diodes (LEDs) consisting of a buried n+-p+ GaN tunnel junction, (In,Ga)N multiple quantum wells (MQWs) and a n+-GaN top layer are grown on single-crystal Ga-polar n+GaN bulk wafers by plasma-assisted molecular beam epitaxy. The (In,Ga)N MQW active regions overgrown on the p+-GaN show chemically abrupt and sharp interfaces in a wide range of compositions and are seen to have high structural and optical properties as verified by X-ray diffraction and spatially resolved cathodoluminescence measurements. The processed LEDs reveal clear rectifying behavior with a low contact and buried tunnel junction resistivity. By virtue of the top n+-GaN layer with a low resistance, excellent current spreading in the LEDs is observed at low currents in this device structure. A few of new device possibilities based on this unique design are discussed. Copyright © 2018, The Authors. All rights reserved.

关键词： Gallium nitride

Evidence for the Higgs Boson Decay to a Z Boson and a Photon at the LHC

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Physical Review Letters 2024年第2期132卷 021803-021803页

作者： G. Aad B. Abbott K. Abeling N. J. Abicht S. H. Abidi A. Aboulhorma H. Abramowicz H. Abreu Y. Abulaiti B. S. Acharya C. Adam Bourdarios L. Adamczyk L. Adamek S. V. Addepalli M. J. Addison J. Adelman A. Adiguzel T. Adye A. A. Affolder Y. Afik M. N. Agaras J. Agarwala A. Aggarwal C. Agheorghiesei A. Ahmad F. Ahmadov W. S. Ahmed S. Ahuja X. Ai G. Aielli A. Aikot M. Ait Tamlihat B. Aitbenchikh I. Aizenberg M. Akbiyik T. P. A. Åkesson A. V. Akimov D. Akiyama N. N. Akolkar K. Al Khoury G. L. Alberghi J. Albert P. Albicocco G. L. Albouy S. Alderweireldt M. Aleksa I. N. Aleksandrov C. Alexa T. Alexopoulos F. Alfonsi M. Algren M. Alhroob B. Ali H. M. J. Ali S. Ali S. W. Alibocus M. Aliev G. Alimonti W. Alkakhi C. Allaire B. M. M. Allbrooke J. F. Allen C. A. Allendes Flores P. P. Allport A. Aloisio F. Alonso C. Alpigiani M. Alvarez Estevez A. Alvarez Fernandez M. Alves Cardoso M. G. Alviggi M. Aly Y. Amaral Coutinho A. Ambler C. Amelung M. Amerl C. G. Ames D. Amidei S. P. Amor Dos Santos K. R. Amos V. Ananiev C. Anastopoulos T. Andeen J. K. Anders S. Y. Andrean A. Andreazza S. Angelidakis A. Angerami A. V. Anisenkov A. Annovi C. Antel M. T. Anthony E. Antipov M. Antonelli F. Anulli M. Aoki T. Aoki J. A. Aparisi Pozo M. A. Aparo L. Aperio Bella C. Appelt A. Apyan N. Aranzabal C. Arcangeletti A. T. H. Arce E. Arena J-F. Arguin S. Argyropoulos J.-H. Arling O. Arnaez H. Arnold G. Artoni H. Asada K. Asai S. Asai N. A. Asbah J. Assahsah K. Assamagan R. Astalos S. Atashi R. J. Atkin M. Atkinson H. Atmani P. A. Atmasiddha K. Augsten S. Auricchio A. D. Auriol V. A. Austrup G. Avolio K. Axiotis G. Azuelos D. Babal H. Bachacou K. Bachas A. Bachiu F. Backman A. Badea P. Bagnaia M. Bahmani A. J. Bailey V. R. Bailey J. T. Baines L. Baines C. Bakalis O. K. Baker E. Bakos D. Bakshi Gupta V. Balakrishnan R. Balasubramanian E. M. Baldin P. Balek E. Ballabene F. Balli L. M. Baltes W. K. Balunas J. Balz E. Banas M. Bandieramonte A. Bandyopadhyay S. Bansal L. Barak M. Barakat E. L. Barberio D. Barberis M. Barbero M. Z. Barel K. N. Barends T. Ba Benemerita Universidad Autonoma de Puebla Puebla Mexico ETH Zurich—Institute for Particle Physics and Astrophysics (IPA) Zurich Switzerland Institute of Nuclear Research ATOMKI Debrecen Hungary National and Kapodistrian University of Athens Athens Greece Escuela Politecnica Nacional Quito Ecuador Faculté des sciences Université Mohammed V Rabat Morocco University of Florida Gainesville Florida USA Fermi National Accelerator Laboratory Batavia Illinois USA University of Ruhuna Department of Physics Matara Sri Lanka INFN Sezione di Bologna Bologna Italy Università di Bologna Bologna Italy Vrije Universiteit Brussel Brussel Belgium AGH University of Krakow Faculty of Physics and Applied Computer Science Krakow Poland The University of Iowa Iowa City Iowa USA Institute Rudjer Boskovic Zagreb Croatia Universidad Iberoamericana Mexico City Mexico Instituto de Física de Cantabria (IFCA) CSIC-Universidad de Cantabria Santander Spain Department of Physics Istanbul University Istanbul Türkiye Imperial College London United Kingdom Baylor University Waco Texas USA Lappeenranta-Lahti University of Technology Lappeenranta Finland Instituto De Alta Investigación Universidad de Tarapacá Casilla 7 D Arica Chile INFN Sezione di Genova Genova Italy Università di Genova Genova Italy Centro de Investigacion y de Estudios Avanzados del IPN Mexico City Mexico Department of Physics Alexandru Ioan Cuza University of Iasi Iasi Romania National Centre for Physics Quaid-I-Azam University Islamabad Pakistan Laboratoire Leprince-Ringuet CNRS/IN2P3 Ecole Polytechnique Institut Polytechnique de Paris Palaiseau France University of Canterbury Christchurch New Zealand Riga Technical University Riga Latvia Department of Modern Physics and State Key Laboratory of Particle Detection and Electronics University of Science and Technology of China Hefei China INFN Sezione di Padova Padova Italy Università di Padova Padova Italy University of Mississippi Oxford Mississi

The first evidence for the Higgs boson decay to a Z boson and a photon is presented, with a statistical significance of 3.4 standard deviations. The result is derived from a combined analysis of the searches performed by the ATLAS and CMS Collaborations with proton-proton collision datasets collected at the CERN Large Hadron Collider (LHC) from 2015 to 2018. These correspond to integrated luminosities of around 140 fb−1 for each experiment, at a center-of-mass energy of 13 TeV. The measured signal yield is 2.2±0.7 times the standard model prediction, and agrees with the theoretical expectation within 1.9 standard deviations.

关键词： Rare decays Higgs bosons W & Z bosons Hadron colliders

Comparative Study onin-situEllipsometric Monitoring of III-Nitride Film Growth via Plasma-Enhanced Atomic Layer Deposition

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International Journal of High Speed Electronics and Systems 2019年第3N04期28卷

作者： Adnan Mohammad Deepa Shukla Saidjafarzoda Ilhom Brian Willis Ali Kemal Okyay Necmi Biyikli University of Connecticut Department of Electrical & Computer Engineering Storrs CT 06269 USA University of Connecticut Department of Materials Science & Engineering Storrs CT 06269 USA University of Connecticut Dept. of Chemical and Biomolecular Engineering Storrs CT 06269 USA Stanford University Department of Electrical Engineering Stanford CA 94305 USA Okyay Technologies Inc. Ankara 06374 Turkey

In this paper a comparative in-situ ellipsometric analysis is carried out on plasma-assisted ALD-grown III-nitride (AlN, GaN, and InN) films. The precursors used are TMA, TMG, and TMI for AlN, GaN, and InN respectively, while Ar is used as purge gas. For all of the films N 2 /H 2 /Ar plasma was used as the co-reactant. The work includes real-time in-situ monitored saturation curves, unit ALD cycle analysis, and >500 cycle film growth runs. In addition, the films are grown at different substrate temperatures to observe the impact of temperature not only on the growth rate but on how it influenced the precursor chemisorption, ligand removal, and nitrogen incorporation surface reactions. All three nitride films confirm fairly linear growth character. The growth rate per cycle (GPC) for each film is also measured with respect to rf-plasma power to obtain the surface saturation conditions during ALD growth. The real-time in-situ monitoring of the film growth can really be beneficial to understand the atomic layer growth and film formation in each individual ALD cycle.

关键词： nitrides plasma atomic layer deposition in-situ ellipsometry and etc

Voltage-induced switching of an antiferromagnetically ordered topological Dirac semimetal

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Physical Review B 2018年第13期97卷 134415-134415页

作者： Youngseok Kim Kisung Kang André Schleife Matthew J. Gilbert Department of Electrical and Computer Engineering University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA Micro and Nanotechnology Laboratory University of Illinois 208 N. Wright Street Urbana Illinois 61801 USA Department of Materials Science and Engineering University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA Frederick Seitz Materials Research Laboratory University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA National Center for Supercomputing Applications University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA

An antiferromagnetic semimetal has been recently identified as a new member of topological semimetals that may host three-dimensional symmetry-protected Dirac fermions. A reorientation of the Néel vector may break the underlying symmetry and open a gap in the quasiparticle spectrum, inducing the (semi)metal-insulator transition. Here, we predict that such a transition may be controlled by manipulating the chemical potential location of the material. We perform both analytical and numerical analysis on the thermodynamic potential of the model Hamiltonian and find that the gapped spectrum is preferred when the chemical potential is located at the Dirac point. As the chemical potential deviates from the Dirac point, the system shows a possible transition from the gapped to the gapless phase and switches the corresponding Néel vector configuration. We perform density functional theory calculations to verify our analysis using a realistic material and discuss a two terminal transport measurement as a possible route to identify the voltage-induced switching of the Néel vector.

关键词： Antiferromagnetism Metal-insulator transition Dirac semimetal Topological materials

MEMS gyroscope for miniaturized space attitude control system

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MEMS gyroscope for miniaturized space attitude control syste...

Design, Test, Integration and Packaging of MEMS/MOEMS

作者： Wajih U Syed Boo Hyun An Mariam S Mansouri Zakriya Mohammed Sultan AlDahmani Ibrahim M Elfadel Daniel S. Choi Department of Electrical and Computer Engineering Masdar Institute at Khalifa University of Science and Technology P.O. Box 54224 Abu Dhabi UAE. Department of Electrical and Computer Engineering Masdar Institute at Khalifa University of Science and Technology Abu Dhabi UAE Department of Mechanical and Materials Engineering Masdar Institute at Khalifa University of Science and Technology Abu Dhabi UAE United Arab Emirates Space Agency Space Missions' Science and Technology Directorate P.O. Box: 7133 Abu Dhabi UAE United Arab Emirates Space Agency Space Missions' Science and Technology Directorate Abu Dhabi UAE

ISBN: (纸本)9781538662007

Space applications impose strict requirements on gyroscope design including high accuracy, precision, shock resistance, reduced non-linearity and sensitivity to external factors such as temperature variation. Vibrating ring gyroscopes (VRG) have been shown to achieve a high scale-factor with low non- linearity while their shock resistance can be enhanced with some structural modifications. They also show a good alignment between the drive and sense-mode resonance frequency and with some tuning, the quadrature error can be nearly eliminated thus minimizing device sensitivity on external factors. We have developed a preliminary design of a VRG with C-shaped innerrings for high shock resistance, which we have been evaluating using a simulation workbench that we have developed using Coventor's MEMS+ and Matlab.

关键词： Gyroscopes Micromechanical devices Electric shock Electrodes Springs Space vehicles Capacitance