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One-step device-independent quantum secure direct communication

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Science China(Physics,Mechanics & Astronomy) 2022年第5期65卷 1-12页

作者： Lan Zhou yu-Bo sheng School of Science Nanjing University of Posts and TelecommunicationsNanjing 210003China College of Electronic and Optical Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Institute of Quantum Information and Technology Nanjing University of Posts and TelecommunicationsNanjing 210003China

Device-independent quantum secure direct communication(DI-QSDC)can relax the security assumptions about the devices’internal working,and effectively enhance QSDC’s *** this paper,we put forward the first hyperentanglement-based one-step DI-QSDC *** this protocol,the communication parties adopt the nonlocal hyperentanglement-assisted complete Bell state analysis,which enables the photons to transmit in the quantum channel for only one *** one-step DI-QSDC can directly transmit 2 bits of messages by a hyperentangled photon pair,and is unconditionally secure in *** with the original DI-QSDC protocol(***.65,12(2020)),the one-step DI-QSDC protocol can simplify the experiment and reduce the message *** particular,with the help of the hyperentanglement heralded amplification and the hyperentanglement purification,the message loss and the message error caused by the channel noise can be completely eliminated,and the communication distance can be largely *** using the photon source with a repetition rate of 10 GHz,the one-step DI-QSDC’s secret message capacity under 50 km communication distance achieves about 7 bit/s with the initial fidelity in each degree of freedom of *** with the quantum repeater,it is possible for researchers to realize the one-step DI-QSDC with an arbitrarily long distance.

关键词： device-independent quantum secure direct communication hyperentanglement nonlocal Bell state analysis

Role of decay in the search for double-charm baryons

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Science China(Physics,Mechanics & Astronomy) 2020年第2期63卷 27-28页

作者： Fu-sheng yu School of Nuclear Science and Technology Lanzhou University

Double-charm baryons,whose components are two heavy charm quarks and one light quark,are part of a large family of hadrons predicted by the quark *** on them are helpful to understand the hadron structure and the nature of the strong *** efforts expended over decades of searching,experimental measurements achieved a breakthrough with the first observation of the double-charm baryon of■^++cc(ccu)via■^++cc→Λ^+c K^-π^+π^+ by the LHCb collaboration in 2017[1].Since then,the LHCb collaboration has been leading the experimental studies for doubly charmed baryons[2-6]because they are produced in considerably large numbers in the Large Hadron Collider(LHC).

关键词： interaction. quark double

Approximation by Neural Networks with Sigmoidal Functions

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Acta Mathematica Sinica,English Series 2013年第10期29卷 2013-2026页

作者： Dan sheng yu Department of Mathematics Hangzhou Normal University

In this paper, we introduce a type of approximation operators of neural networks with sigmodal functions on compact intervals, and obtain the pointwise and uniform estimates of the ap- proximation. To improve the approximation rate, we further introduce a type of combinations of neurM networks. Moreover, we show that the derivatives of functions can also be simultaneously approximated by the derivatives of the combinations. We also apply our method to construct approximation operators of neural networks with sigmodal functions on infinite intervals.

关键词： Feedforward neural networks sigmoidal functions simultaneous approximation combi-nations

The China Seismological Reference Model project

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Earth and Planetary Physics 2023年第5期7卷 521-532页

作者： LianXing Wen sheng yu Department of Geosciences State University of New York at Stony BrookStony BrookNY 11794USA Laboratory of Seismology and Physics of Earth’s Interior School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Department of Earth Sciences National Natural Science Foundation of ChinaBeijing 100085China

The importance of developing high-resolution seismic models to improve understanding of tectonic processes and enhance seismic hazard mitigation programs,along with the rapid expansion of seismic coverage in China,called for a seismological reference model to be established in *** China Seismological Reference Model(CSRM)project was initiated by the National Natural Science Foundation of China with two primary goals:(1)the CSRM would serve as a primary source for the current state of seismological research in China,and(2)the seismic data and constraints used to construct the CSRM would be used as a backbone open-access cyberinfrastructure for future research in *** CSRM project was also intended to promote data exchange and scientific collaboration in seismology in ***,two parallel efforts of the project are being pursued:(1)construction of the CSRM,and(2)development of a CSRM product *** CSRM is jointly constrained by various types of seismic constraints extracted from the seismic data recorded at 4511 seismic stations in continental China following a top-down approach,with the seismic structures in the shallower part of the Earth constrained *** of the CSRM involves three preparation steps:(1)building datasets of various seismic constraints from the seismic data,(2)developing a method to incorporate the constraints of surface wave observations from regional earthquakes into the inversion of the seismic structure,and(3)constructing high-resolution pre-CSRM seismic models of the velocity structure in the shallow crust and the Pn-velocity structure in the uppermost *** the final process,the CSRM will be constructed by jointly inverting all the seismic constraints using the pre-CSRM models as starting models or a priori *** CSRM product center(http://***)archives and distributes three types of products:CSRM models,the Level 1 original seismic data used to extract seismic constraints

关键词： China Seismological Reference Model seismic structure seismic hazard tectonics continental China

Synthesis of High Molecular Weight Polyethylene and E-MA Copolymers Using Iminopyridine Ni(Ⅱ) and Pd(Ⅱ) Complexes Containing a Flexible Backbone and Rigid Axial Substituents

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Chinese Journal of Polymer Science 2023年第2期41卷 233-239页

作者： yu-Dan Liao Qi Cai sheng-yu Dai School of Chemical and Environmental Engineering Anhui Polytechnic UniversityWuhu241000China Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei230601China

Suppressing the chain transfer reactions during polymerization in late-transition metal-catalyzed olefin polymerization systems is the key to obtaining high molecular weight polyolefin materials. In this work, two efficient strategies(“sandwich” and rotation-restricted strategies)to retard chain transfer reactions in ethylene(co)polymerization were employed for the iminopyridyl system. Herein, a family of iminopyridyl Ni(Ⅱ)and Pd(Ⅱ) complexes with a flexible backbone and rigid axial bulky aryl substituents were designed, synthesized and characterized. In ethylene polymerization, the iminopyridyl Ni(Ⅱ) and Pd(Ⅱ) catalysts using the two strategies exhibited reasonable activities and generated highly branched polyethylenes with high molecular weights, where catalysts with dibenzosuberyl substituents exhibited significantly higher activities and produced higher molecular weight polyethylene than catalysts with 8-arylnaphthalenyl substituent. A similar trend of activities and molecular weights was also found in the copolymerization of ethylene with MA using the Pd(Ⅱ) catalysts. Moreover, highly branched E-MA copolymers with moderate to high molecular weights and high incorporation ratios(up to 17.4 mol%) were generated with the two Pd(Ⅱ) catalysts. Most interestingly, as compared with the dibenzhydryl Ni(Ⅱ) and Pd(Ⅱ) catalysts, the catalysts using the two strategies exhibited a superior ability to retard the chain transfer reactions and generated polymers and copolymers with 1-2 orders of magnitude higher molecular weights during ethylene(co)polymerization.

关键词： Ni(Ⅱ)and Pd(Ⅱ) Suppressing chain transfer High molecular weight Ethylene(co)polymerization

EFFECTS OF LIQUID COMPRESSIBILITY ON RADIAL OSCILLATIONS OF GAS BUBBLES IN LIQUIDS

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Journal of Hydrodynamics 2012年第5期24卷 760-766页

作者： ZHANG yu-ning LI sheng-cai School of Engineering University of Warwick Coventry UK CV4 7AL

For forced radial oscillations of gas bubbles in liquids, a more rigorous expression of the acoustic damping constant based on Keller＇s equation is developed. Comparison with those in published papers is also made. The expression offered in this paper will improve the predictions of total damping constant in particular for high frequencies and large bubbles, i.e., large ωR0 / c1 （ ω is the frequency of driving sound field, Ro is the equilibrium bubble radius, c1 is the sound speed in the liquid）. Examples in ultrasound imaging and acoustical oceanography are demonstrated.

关键词： gas bubble damping constant liquid compressibility natural frequency

Distributed secure quantum machine learning

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Science Bulletin 2017年第14期62卷 1025-1029页

作者： yu-Bo sheng Lan Zhou Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education College of Mathematics & Physics Nanjing University of Posts and Telecommunications

Distributed secure quantum machine learning （DSQML） enables a classical client with little quantum technology to delegate a remote quantum machine learning to the quantum server with the privacy data preserved. Moreover, DSQML can be extended to a more general case that the client does not have enough data, and resorts both the remote quantum server and remote databases to perform the secure machi~ learning. Here we propose a DSQML protocol that the client can classify two-dimensional vectors to dif- ferent clusters, resorting to a remote small-scale photon quantum computation processor. The protocol is secure without leaking any relevant information to the Eve. Any eavesdropper who attempts to intercept and disturb the learning process can be noticed. In principle, this protocol can be used to classify high dimensional vectors and may provide a new viewpoint and application for future ＂big data＂.

关键词： Quantum machine learning Quantum communication Quantum computation Big data

Demonstration of high-dimensional controlled quantum teleportation for the first time

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 163-164页

作者： yu-Bo sheng Lan Zhou College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023China College of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China

Controlled quantum teleportation(CQT) [1] is the tripartite version of quantum teleportation and it allows the teleportation of an unknown quantum state under the control of a third party. Compared with low-dimensional counterparts,high-dimensional CQT can exhibit larger information transmission capacity and a higher control power [2,3].

关键词： quantum dimensional high

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Heralded amplification of single-photon entanglement with polarization feature

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Frontiers of physics 2018年第5期13卷 241-249页

作者： yu-yu Jin sheng-Xian Qin Hao Zu Lan Zhou Wei Zhong yu-Bo sheng School of Science Nanjing University of Posts and Telecommunications Nanjing 210003 China New Energy Technology Engineering Laboratory of Jiangsu Province Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China Institute of Signal Processing Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China

Heralded noiseless amplification is beneficial in overcoming transmission photon loss in a noisy quantum channel. We propose a single-photon-assisted heralded noiseless amplification protocol of the single- photon entanglement （SPE）, where the single-photon qubit has an arbitrary unknown polarization feature. We focus on both the complete and partial photon loss during the transmission process. After the amplification, the parties can recover the pure less-entangled SPE into a maximally entangled SPE and increase its fidelity. Moreover, the polarization feature of the single-photon qubit will be well preserved and not be leaked. Our protocol can be realized under our current experimental condition. Based on the features above, our protocol may be useful in the quantum secure communication schemes that encode information in the polarization degree of freedom of photons.

关键词： quantum communication single-photon entanglement quantum state amplification polarization feature