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Collective Molecular Machines: Multidimensionality and Reconfigurability
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作者 Bin Wang Yuan Lu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期309-340,共32页
Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical work.During the last 60 years,designing molecular structures capable of generat... Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical work.During the last 60 years,designing molecular structures capable of generating unidirectional mechanical motion at the nanoscale has been the topic of intense research.Effective progress has been made,attributed to advances in various fields such as supramolecular chemistry,biology and nanotechnology,and informatics.However,individual molecular machines are only capable of producing nanometer work and generally have only a single functionality.In order to address these problems,collective behaviors realized by integrating several or more of these individual mechanical units in space and time have become a new paradigm.In this review,we comprehensively discuss recent developments in the collective behaviors of molecular machines.In particular,collective behavior is divided into two paradigms.One is the appropriate integration of molecular machines to efficiently amplify molecular motions and deformations to construct novel functional materials.The other is the construction of swarming modes at the supramolecular level to perform nanoscale or microscale operations.We discuss design strategies for both modes and focus on the modulation of features and properties.Subsequently,in order to address existing challenges,the idea of transferring experience gained in the field of micro/nano robotics is presented,offering prospects for future developments in the collective behavior of molecular machines. 展开更多
关键词 Molecular machines collective control collective behaviors DNA Biomolecular motors
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Properties of collective flow and pion production in intermediate-energy heavy-ion collisions with a relativistic quantum molecular dynamics model
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作者 Si-Na Wei Zhao-Qing Feng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期155-169,共15页
The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(LQMD.RMF). Using the LQMD.RMF, the properties of collective flow and pion production were investigated sys... The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(LQMD.RMF). Using the LQMD.RMF, the properties of collective flow and pion production were investigated systematically for nuclear reactions with various isospin asymmetries. The directed and elliptic flows of the LQMD.RMF are able to describe the experimental data of STAR Collaboration. The directed flow difference between free neutrons and protons was associated with the stiffness of the symmetry energy, that is, a softer symmetry energy led to a larger flow difference. For various collision energies, the ratio between the π^(-) and π^(+) yields increased with a decrease in the slope parameter of the symmetry energy. When the collision energy was 270 MeV/nucleon, the single ratio of the pion transverse momentum spectra also increased with decreasing slope parameter of the symmetry energy in both nearly symmetric and neutron-rich systems.However, it is difficult to constrain the stiffness of the symmetry energy with the double ratio because of the lack of threshold energy correction on the pion production. 展开更多
关键词 Heavy-ion collision collective flow Pion production Symmetry energy Relativistic mean field
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Opinion consensus incorporating higher-order interactions in individual-collective networks
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作者 叶顺 涂俐兰 +2 位作者 王先甲 胡佳 王薏潮 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期105-115,共11页
In the current information society, the dissemination mechanisms and evolution laws of individual or collective opinions and their behaviors are the research hot topics in the field of opinion dynamics. First, in this... In the current information society, the dissemination mechanisms and evolution laws of individual or collective opinions and their behaviors are the research hot topics in the field of opinion dynamics. First, in this paper, a two-layer network consisting of an individual-opinion layer and a collective-opinion layer is constructed, and a dissemination model of opinions incorporating higher-order interactions(i.e. OIHOI dissemination model) is proposed. Furthermore, the dynamic equations of opinion dissemination for both individuals and groups are presented. Using Lyapunov's first method,two equilibrium points, including the negative consensus point and positive consensus point, and the dynamic equations obtained for opinion dissemination, are analyzed theoretically. In addition, for individual opinions and collective opinions,some conditions for reaching negative consensus and positive consensus as well as the theoretical expression for the dissemination threshold are put forward. Numerical simulations are carried to verify the feasibility and effectiveness of the proposed theoretical results, as well as the influence of the intra-structure, inter-connections, and higher-order interactions on the dissemination and evolution of individual opinions. The main results are as follows.(i) When the intra-structure of the collective-opinion layer meets certain characteristics, then a negative or positive consensus is easier to reach for individuals.(ii) Both negative consensus and positive consensus perform best in mixed type of inter-connections in the two-layer network.(iii) Higher-order interactions can quickly eliminate differences in individual opinions, thereby enabling individuals to reach consensus faster. 展开更多
关键词 two-layer social networks individual and collective opinions higher-order interactions CONSENSUS Lyapunov's first method
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Geometric regulation of collective cell tangential ordering migration
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作者 Hao Dong Yuming Zhou +8 位作者 Xuehe Ma Junfang Liu Fulin Xing Jianyu Yang Qiushuo Sun Qingsong Hu Fen Hu Leiting Pan Jingjun Xu 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第2期94-103,共10页
Collective cell migration is a coordinated movement of multi-cell systems essential for various processes throughout life.The collective motions often occur under spatial restrictions,hallmarked by the collective rota... Collective cell migration is a coordinated movement of multi-cell systems essential for various processes throughout life.The collective motions often occur under spatial restrictions,hallmarked by the collective rotation of epithelial cells confined in circular substrates.Here,we aim to explore how geometric shapes of confinement regulate this collective cell movement.We develop quantitative methods for cell velocity orientation analysis,and find that boundary cells exhibit stronger tangential ordering migration than inner cells in circular pattern.Furthermore,decreased tangential ordering movement capability of collective cells in triangular and square patterns are observed,due to the disturbance of cell motion at unsmooth corners of these patterns.On the other hand,the collective cell rotation is slightly affected by a convex defect of the circular pattern,while almost hindered with a concave defect,also resulting from different smoothness features of their boundaries.Numerical simulations employing cell Potts model well reproduce and extend experimental observations.Together,our results highlight the importance of boundary smoothness in the regulation of collective cell tangential ordering migration. 展开更多
关键词 collective cell migration spatial restrictions tangential ordering geometric regula-tion cell Potts model
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Jeanologia advocates for collective solutions to address global water scarcity
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《China Textile》 2024年第2期44-45,共2页
Coinciding with World Water Day celebrations and under the slogan"Water,a shared responsibility,"the eco-efficient textile technology company,Jeanologia,calls on this productive sector,appealing for a real c... Coinciding with World Water Day celebrations and under the slogan"Water,a shared responsibility,"the eco-efficient textile technology company,Jeanologia,calls on this productive sector,appealing for a real change,away from greenwashing and towards concrete and collective action. 展开更多
关键词 collective productive SECTOR
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Study on the Impact of Collective Commercial Construction Land Entering the Market on Rural Residents’Income:Taking Deqing County,Zhejiang Province as an Example
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作者 Panpan He Haolong Zhao 《Proceedings of Business and Economic Studies》 2024年第4期53-59,共7页
The entry of collective construction land for business purposes is an important measure for deepening the reform of the rural land system,promoting the flow of urban and rural factors,and realizing rural revitalizatio... The entry of collective construction land for business purposes is an important measure for deepening the reform of the rural land system,promoting the flow of urban and rural factors,and realizing rural revitalization.Since the production of the first batch of pilot projects in 2015,33 county-level cities have participated in the pilot policy by 2023.Deqing County,Zhejiang Province,as the first area to participate in the pilot project,aims to achieve more fruitful results.This paper first examines how promoting farmers’income through the market entry of agricultural land can be achieved,then uses the synthetic control method to quantitatively study the impact of collective operational construction land on farmers’income using panel data from 2011 to 2019,and finally proposes relevant suggestions from the perspective of system reform. 展开更多
关键词 collective operational construction land into the market Farmers’income Synthetic control method
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Multi-user quantum key distribution with collective eavesdropping detection over collective-noise channels 被引量:2
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作者 黄伟 温巧燕 +1 位作者 刘斌 高飞 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期114-124,共11页
A multi-user quantum key distribution protocol is proposed with single particles and the collective eavesdropping detection strategy on a star network. By utilizing this protocol, any two users of the network can acco... A multi-user quantum key distribution protocol is proposed with single particles and the collective eavesdropping detection strategy on a star network. By utilizing this protocol, any two users of the network can accomplish quantum key distribution with the help of a serving center. Due to the utilization of the collective eavesdropping detection strategy, the users of the protocol just need to have the ability of performing certain unitary operations. Furthermore, we present three fault-tolerant versions of the proposed protocol, which can combat with the errors over different collective-noise channels.The security of all the proposed protocols is guaranteed by the theorems on quantum operation discrimination. 展开更多
关键词 quantum cryptography quantum key distribution collective eavesdropping detection collective noise
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Collective Hamiltonian for Multi-O(4) Model 被引量:1
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作者 GU Jian-Zhong Masato Kobayasi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期309-316,共8页
The collective Bamiltonian up to the fourth order for multi-O(4) model is derived based on the self-consistent collective-coordinate (SCC) method, which is formulated in the framework of the time-dependent Hartree... The collective Bamiltonian up to the fourth order for multi-O(4) model is derived based on the self-consistent collective-coordinate (SCC) method, which is formulated in the framework of the time-dependent Hartree-Bogoliubov (TDHB) theory. The validity of the collective Hamiltonian is checked in the two special cases of the multi-O(4) model: the case where the number of the shells is equal to one (a single j-shell case), and the case where the Hartree-Bogoliubov equilibrium point is spherical (the spherical case). The collective Hamiltonian constitutes a good starting point to study nuclear shape coexistence. 展开更多
关键词 self-consistent collective-coordinate method multi-O(4) model time-dependent Hartree-Bogoliubov theory collective Hamiltonian
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MPI-IO中Collective I/O的优化
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作者 李胜利 张琦 +1 位作者 陈宝利 张浩 《计算机工程与科学》 CSCD 2005年第2期65-67,共3页
本文对MPI-IO库中Collective I/O的实现算法Two-phase I/O提出了改进。通过选取主联络进程来减少第 一阶段进程间的通信量,从而减少Two-phase I/O方法在通信过程中的时间消耗,提高了整体的I/O性能。
关键词 MPI-IO collective I/O算法 计算机 优化
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Practice Mode and Value Research of Reform of Rural Collective Economy Property Right System in Beijing Rural-urban Continuum
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作者 方嘉雯 《Agricultural Science & Technology》 CAS 2014年第6期1058-1064,共7页
In the research, reform of rural collective economy property right system in Beijing rural-urban continuum was explored in terms of background, cause, pro- cess and practice modes by surveying and interviewing, and th... In the research, reform of rural collective economy property right system in Beijing rural-urban continuum was explored in terms of background, cause, pro- cess and practice modes by surveying and interviewing, and the value of system reform on urbanization in rural areas was illustrated from the perspective of farmers who lose lands. The results showed that since reform and opening-up, disadvan- tages of collective economy property are always the fundamental cause of reform; rural-urban contradiction produced from rapid urbanization makes the reform much more urgent; shareholding co-operative system is the essence of reform of collective economy property right system. Rural collective economy property right system in Beijing includes stock-assets quantification shareholding co-operative system, share- capitalization of contractual land management right, farmers as shareholders by investment, and resource and capital mode, with advantages and disadvantages respectively. The common character should be noticed is that all modes have share on contractual right of land, indicating the core of the reform of property system lies in asset quantification and stock quota. In improving urban-rural integration and modern market system, as well as endowing more rights to farmers, reform of rural collective economy property right system is of great significance, which provides a transition space and buffer mechanism for urbanization in rural areas. 展开更多
关键词 Rural collective economy property right system Shareholding co-opera-tive system Land rights and interests Buffer mechanism
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Nonlinear interactions and quantum entanglement for collective fields in near-resonantly driven systems
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作者 张秀 胡响明 +1 位作者 张雪华 王飞 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期263-268,共6页
This paper proposes a novel form of multimode nonlinear interactions by using a near-resonantly dressed atomic ensemble in an optical cavity. Due to quantum interference, a pair of collective fields come into the bili... This paper proposes a novel form of multimode nonlinear interactions by using a near-resonantly dressed atomic ensemble in an optical cavity. Due to quantum interference, a pair of collective fields come into the bilinear interactions, whose strengths are proportional to the population difference between dressed states which are coupled to the collective fields. By such an interaction, it is possible to obtain perfect multimode squeezing and collective Einstein-Podolsky-Rosen (EPR) entanglement in the cavity output. 展开更多
关键词 collective parametric interaction quantum interference collective EPR entanglement multimode squeezing
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Constructing Representative Collective Signature Protocols Using The GOST R34.10-1994 Standard
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作者 Tuan Nguyen Kim Duy Ho Ngoc Nikolay A.Moldovyan 《Computers, Materials & Continua》 SCIE EI 2023年第1期1475-1491,共17页
The representative collective digital signature,which was suggested by us,is built based on combining the advantages of group digital signature and collective digital signature.This collective digital signature schema... The representative collective digital signature,which was suggested by us,is built based on combining the advantages of group digital signature and collective digital signature.This collective digital signature schema helps to create a unique digital signature that deputizes a collective of people representing different groups of signers and may also include personal signers.The advantage of the proposed collective signature is that it can be built based on most of the well-known difficult problems such as the factor analysis,the discrete logarithm and finding modulo roots of large prime numbers and the current digital signature standards of the United States and Russian Federation.In this paper,we use the discrete logarithmic problem on prime finite fields,which has been implemented in the GOST R34.10-1994 digital signature standard,to build the proposed collective signature protocols.These protocols help to create collective signatures:Guaranteed internal integrity and fixed size,independent of the number of members involved in forming the signature.The signature built in this study,consisting of 3 components(U,R,S),stores the information of all relevant signers in the U components,thus tracking the signer and against the“disclaim of liability”of the signer later is possible.The idea of hiding the signer’s public key is also applied in the proposed protocols.This makes it easy for the signing group representative to specify which members are authorized to participate in the signature creation process. 展开更多
关键词 Signing collective signing group discrete logarithm group signature collective signature GOST standards
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Constructing Collective Signature Schemes Using Problem of Finding Roots Modulo
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作者 Tuan Nguyen Kim Duy Ho Ngoc Nikolay A.Moldovyan 《Computers, Materials & Continua》 SCIE EI 2022年第7期1105-1122,共18页
Digital signature schemes are often built based on the difficulty of the discrete logarithm problems,of the problem of factor analysis,of the problem of finding the roots modulo of large primes or a combination of the... Digital signature schemes are often built based on the difficulty of the discrete logarithm problems,of the problem of factor analysis,of the problem of finding the roots modulo of large primes or a combination of the difficult problems mentioned above.In this paper,we use the new difficult problem,which is to find the wth root in the finite ground field GF(p)to build representative collective signature schemes,but the chosen modulo p has a special structure distinct p=Nt_(0)t_(1)t_(2)+1,where N is an even number and t_(0),t_(1),t_(2) are prime numbers of equal magnitude,about 80 bits.The characteristics of the proposed scheme are:i)The private key of each signer consists of 2 components(K_(1),K_(2)),randomly selected,but the public key has only one component(Y)calculated by the formula Y=K_(w)^(1)_(1) K^(w)_(2)^(2);w_(1)=t_(0)t_(1) and w_(2)=t_(0)t_(2);and ii)The generated signature consists of a set of 3 components(e,S_(1),S_(2)).We use the technique of hiding the signer’s public key Y,which is the coefficientλgenerated by the group nanager,in the process of forming the group signature and representative collective signature to enhance the privacy of all members of the signing collective. 展开更多
关键词 Computing roots finding roots modulo collective signature signing collective signing group
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Notes on Quantitative Structure-Properties Relationships (QSPR) Part Four: Quantum Multimolecular Polyhedra, Collective Vectors, Quantum Similarity, and Quantum QSPR Fundamental Equation
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作者 Ramon Carbo-Dorca Silvia Gonzalez 《Management Studies》 2016年第1期33-47,共15页
The nature and origin of a fundamental quantum QSPR (QQSPR) equation are discussed. In principle, as any molecular structure can be associated to quantum mechanical density functions (DF), a molecular set can be r... The nature and origin of a fundamental quantum QSPR (QQSPR) equation are discussed. In principle, as any molecular structure can be associated to quantum mechanical density functions (DF), a molecular set can be reconstructed as a quantum multimolecular polyhedron (QMP), whose vertices are formed by each molecular DF. According to QQSPR theory, complicated kinds of molecular properties, like biological activity or toxicity, of molecular sets can be calculated via the quantum expectation value of an approximate Hermitian operator, which can be evaluated with the geometrical information contained in the attached QMP via quantum similarity matrices. Practical ways of solving the QQSPR problem from the point of view of QMP geometrical structure are provided. Such a development results into a powerful algorithm, which can be implemented within molecular design as an alternative to the current classical QSPR procedures. 展开更多
关键词 quantum similarity quantum multimolecular polyhedra (QMP) quantum QSPR (QQSPR) QQSPR fundamental equation QMP statistical-like collective functions QMP condensed collective indices classical QSPR-QSAR
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Individual Identity and Collective Identity in Ralph Ellison's Invisible Man
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作者 韩秀 《海外英语》 2015年第8期153-155,共3页
Ralph Ellison’s Invisible Man deals with the identity issue fundamental for black Americans to reestablish themselves in the white-dominated society.While the narrator suffers from identity crisis in multiples ways,t... Ralph Ellison’s Invisible Man deals with the identity issue fundamental for black Americans to reestablish themselves in the white-dominated society.While the narrator suffers from identity crisis in multiples ways,the paper focuses on the conflict between his need to build a distinctive individual identity with the prerequisite to surrender to collective identity in order to blend in the group. 展开更多
关键词 INVISIBLE MAN INDIVIDUAL IDENTITY collective IDENTITY
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Collective Oriented Culture and Its Negative Impact upon Oral English Teaching
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作者 肖春艳 约翰.史密斯 《疯狂英语(教师版)》 2015年第3期76-77,81,共3页
As one of the most distinguished features of Chinese Culture,collective oriented culture is the deep structure of Chinese cultural psychology which has shaped Chinese character and influenced their behavior.As a resul... As one of the most distinguished features of Chinese Culture,collective oriented culture is the deep structure of Chinese cultural psychology which has shaped Chinese character and influenced their behavior.As a result of it,Chinese students suffer this negative effect from collective orientated culture when acquiring English,especially in oral English acquisition.TEFL teachers should be aware of cultural psychology and try their best to minimize its negative effect instead of neglecting or even enlarging it during oral English teaching. 展开更多
关键词 collective oriented culture negative effect oral English teaching
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Collective Signature Schemes Problem of Finding Roots Modulo
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作者 Hailyie Tekleselassie 《Journal of Electronic & Information Systems》 2022年第1期1-9,共9页
Digital signature schemes in general and representative collective digital signature schemes,in particular,are often built based on the difficulty of the discrete logarithm problem on the finite field,of the discrete ... Digital signature schemes in general and representative collective digital signature schemes,in particular,are often built based on the difficulty of the discrete logarithm problem on the finite field,of the discrete logarithm problem of the elliptic curve,of the problem of factor analysis,of the problem of finding the roots modulo of large primes or a combination of the difficult problems mentioned above.In this paper,we use the new difficult problem,which is to find W^(th)the root in the finite ground field to build representative collective signature schemes,but the chosen modulo has a special structure distinct p=Nt_(0)t_(1)t_(2)+1,where is an even number and t_(0),t_(1),t_(2)are prime numbers of equal magnitude,about 80bits.The characteristics of the proposed scheme are:i)The private key of each signer consists of 2 components(K_(1),K_(2)),randomly selected,but the public key has only one component(Y)calculated by the formula Y=K^(W_(1))_(1)K^(W_(2))_(2);and t_(0)t_(2);and ii)The generated signature consists of a set of 3 components(e,S_(1),S_(2)).We use the technique of hiding the signer’s public key Y,which is the coefficientλgenerated by the group manager,in the process of forming the group signature and representative collective signature to enhance the privacy of all members of the signing collective. 展开更多
关键词 Computing roots Finding roots modulo collective signature Signing collective Signing group
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Research on Rural Collective Land Ownership Confirmation Based on Unified Registration of Real Estate 被引量:1
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作者 况婷 胡细英 《Agricultural Science & Technology》 CAS 2017年第12期2650-2652,共3页
Rural collective land ownership registration is a basic work to safeguard farmers' land rights and interests, and promote rural reform and development, which involves the vital interests of the peasants, and has grea... Rural collective land ownership registration is a basic work to safeguard farmers' land rights and interests, and promote rural reform and development, which involves the vital interests of the peasants, and has great influence on the rural economic and social development. However, there are many problems in rural col- lective land ownership registration and certification, such as unclear rural land own- ership subject and nature; not unified understanding of registration, no high enthusi- asm of the grass-roots work; prominent registration policy contradictions, serious shortage of investment, which seriously affect the rural land ownership registration work. In order to solve these problems, some suggestions are put forward on pro- moting the rural land ownership registration work smoothly. 展开更多
关键词 Real estate registration Rural collective land Right confirmation
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Fault tolerant quantum secure direct communication with quantum encryption against collective noise 被引量:9
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作者 黄伟 温巧燕 +2 位作者 贾恒越 秦素娟 高飞 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第10期101-109,共9页
We present two novel quantum secure direct communication(QSDC) protocols over different collective-noise channels.Different from the previous QSDC schemes over collective-noise channels,which are all source-encrypti... We present two novel quantum secure direct communication(QSDC) protocols over different collective-noise channels.Different from the previous QSDC schemes over collective-noise channels,which are all source-encrypting protocols,our two protocols are based on channel-encryption.In both schemes,two authorized users first share a sequence of EPR pairs as their reusable quantum key.Then they use their quantum key to encrypt and decrypt the secret message carried by the decoherence-free states over the collective-noise channel.In theory,the intrinsic efficiencies of both protocols are high since there is no need to consume any entangled states including both the quantum key and the information carriers except the ones used for eavesdropping checks.For checking eavesdropping,the two parties only need to perform two-particle measurements on the decoy states during each round.Finally,we make a security analysis of our two protocols and demonstrate that they are secure. 展开更多
关键词 quantum cryptography quantum secure direct communication quantum encryption collective noise
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Landau damping of collective modes in a harmonically trapped Bose-Einstein condensate 被引量:4
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作者 马晓栋 周昱 +1 位作者 马永利 黄国翔 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第8期1871-1878,共8页
This paper proposes a method for calculating the Landau damping of a low-energy collective mode in a harmonically trapped Bose-Einstein condensate. Based on the divergence-free analytical solutions for ground-state wa... This paper proposes a method for calculating the Landau damping of a low-energy collective mode in a harmonically trapped Bose-Einstein condensate. Based on the divergence-free analytical solutions for ground-state wavefunction of the condensate and eigenvalues and eigenfunctions for thermally excited quasiparticles, obtained beyond Thomas-Fermi approximation, this paper calculates the coupling matrix elements describing the interaction between the collective mode and the quasiparticles. With these analytical results this paper evaluates the Landau damping rate of a monopole mode in a spherical trap and discusses its dependence on temperature, particle number and trapping frequency of the system. 展开更多
关键词 Bose-Einstein condensation collective modes Landau damping
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