共查询到20条相似文献,搜索用时 46 毫秒
1.
A threshold proxy quantum signature scheme with threshold shared verification is proposed. An original signer could authorize
a group as its proxy signers. Then only t or more of n persons in the proxy group can generate the proxy signature on behalf of the original signer and any t − 1 or fewer ones cannot do that. When the proxy signature needs to be verified, any t or more of n persons belonging to the verification group can verify the message and any t − 1 or fewer ones cannot verify the validity of the proxy signature.
Supported by the National Basic Research Program of China (973 Program)(Grant No. 2007CB311100), the National High-Technology
Research and Development Program of China (Grant Nos. 2006AA01Z419 and 20060101Z4015), the Major Research Plan of the National
Natural Science Foundation of China (Grant No. 90604023), the Scientific Research Common Program of Beijing Municipal Commission
of Education (Grant No. KM200810005004), the Scientific Research Foundation for the Youth of Beijing University of Technology
(Grant No. 97007016200701), the Doctoral Scientific Research Activation Foundation of Beijing University of Technology (Grant
No. 52007016200702), and the National Laboratory for Modern Communications Science Foundation of China (Grant No. 9140C1101010601) 相似文献
2.
For the first time, a threshold quantum secure direct communication (TQSDC) scheme is presented. Similar to the classical Shamir's secret sharing scheme, the sender makes n shares, S1, …, Sn of secret key K and each receiver keeps a share secretly. If the sender wants to send a secret message M to the receivers, he en-codes the information of K and M on a single photon sequence and sends it to one of the receivers. According to the secret shares, the t receivers sequentially per-form the corresponding unitary operations on the single photon sequence and ob-tain the secret message M. The shared shares may be reusable if it can be judged that there is no eavesdropper in line. We discuss that our protocol is feasible with current technology. 相似文献
3.
Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the
users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol, the TTP shares a random key
K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA, the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share, each user performs the corresponding unitary operations on the single photon sequence
sequentially. At last, the TTP can judge whether the impersonator exists. The second protocol is a modified version with a
circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technology.
Supported by the National Basic Research Program of China (973 Program) (Grant No. 2007CB311100), the National High Technology
Research and Development Program of China (Grant Nos. 2006AA01Z419 and 20060101Z4015), the Major Research Plan of the National
Natural Science Foundation of China (Grant No. 90604023), the Scientific Research Common Program of Beijing Municipal Commission
of Education (Grant No. KM200810005004), the Scientific Research Foundation for the Youth of Beijing University of Technology
(Grant No. 97007016200701), the National Research Foundation for the Doctoral Program of Higher Education of China (Grant
No. 20040013007), the National Laboratory for Modern Communications Science Foundation of China (Grant No. 9140C1101010601),
and the Doctor Scientific Research Activation Foundation of Beijing University of Technology (Grant No. 52007016200702) 相似文献
4.
A threshold quantum secret sharing (TQSS) scheme between multi-party and multi-party was proposed using a sequence of single
photons, which is useful and efficient when the parties of communication are not all present. We described the process of
this TQSS scheme and discussed its security. It was shown that entanglement is not necessary for quantum secret sharing. Moreover,
the theoretic efficiency was improved to approach 100% as almost all the instances can be used for generating the private
key, and each photon can carry one bit of information. This protocol is feasible with the present-day technique.
Supported by the National Basic Research Program of China (973 Program)(Grant No. 2007CB311100), the National High-Technology
Research and Development Program of China (Grant Nos. 2006AA01Z419 and 2006AA01Z440), the Major Research Plan of the National
Natural Science Foundation of China (Grant No. 90604023), the Scientific Research Common Program of Beijing Municipal Commission
of Education (Grant No. KM200810005004), the Scientific Research Foundation for the Youth of Beijing University of Technology
(Grant No. 97007016200701), the Doctoral Scientific Research Activation Foundation of Beijing University of Technology (Grant
No. 52007016200702), the ISN Open Foundation, and the National Laboratory for Modern Communications Science Foundation of
China (Grant No. 9140C1101010601) 相似文献
5.
From the perspective of information theory and cryptography, the security of two quantum dialogue protocols and a bidirectional
quantum secure direct communication (QSDC) protocol was analyzed, and it was pointed out that the transmitted information
would be partly leaked out in them. That is, any eavesdropper can elicit some information about the secrets from the public
annunciations of the legal users. This phenomenon should have been strictly forbidden in a quantum secure communication. In
fact, this problem exists in quite a few recent proposals and, therefore, it deserves more research attention in the following
related study.
Supported by the National High Technology Research and Development Program of China (Grant No. 2006AA01Z419), the National
Natural Science Foundation of China (Grant Nos. 90604023 and 60373059), the National Research Foundation for the Doctoral
Program of Higher Education of China (Grant No. 20040013007), the National Laboratory for Modern Communications Science Foundation
of China (Grant No. 9140C1101010601), the Natural Science Foundation of Beijing (Grant No. 4072020) and the ISN Open Foundation 相似文献
6.
The way to compare the efficiencies of different detect strategies (DSs) in the “ping-pong” protocol is studied. The trade-off
between information gain and disturbance is calculated and compared for different DSs. The comparison result primely tallies
with our intuitional analysis. It is shown that the analysis of this trade-off is a feasible way to compare the performances
of different DSs in theory.
Supported by the National High Technology Research and Development Program of China (Grant No. 2006AA01Z419), the National
Natural Science Foundation of China (Grant Nos. 90604023 and 6087319), the National Laboratory for Modern Communications Science
Foundation of China (Grant No. 9140C1101010601), the Natural Science Foundation of Beijing (Grant No. 4072020), and the ISN
Open Foundation. 相似文献
7.
We present a scheme for remotely preparing a general two-particle entangled state via two tripartite W entangled states of different amplitudes. In this scheme one sender and two remote receivers are involved. The sender can
help either one of the receivers to remotely reconstruct the original state with the aid of the other receiver’s two single-particle
orthogonal measurements. It is shown that by means of the method of the positive operator-valued measurement, our remote state
preparation scheme can be achieved probabilistically.
This project supported by the National Key Basic Research and Development Program of China under Grant No. 2006CB921604 and
the National Natural Science Foundation of China under Grant Nos. 60578050 and 10434060. 相似文献
8.
An efficient quantum secure direct communication protocol is presented over the amplitude damping channel. The protocol encodes
logical bits in two-qubit noiseless states, and so it can function over a quantum channel subjected to collective amplitude
damping. The feature of this protocol is that the sender encodes the secret directly on the quantum states, the receiver decodes
the secret by performing determinate measurements, and there is no basis mismatch. The transmission’s safety is ensured by
the nonorthogonality of the noiseless states traveling forward and backward on the quantum channel. Moreover, we construct
the efficient quantum circuits to implement channel encoding and information encoding by means of primitive operations in
quantum computation.
Supported by the National Natural Science Foundation of China (Grant Nos. 60873191 and 60821001), the Specialized Research
Fund for the Doctoral Program of Higher Education (Grant No. 200800131016), the Natural Science Foundation of Beijing (Grant
No. 4072020), the National Laboratory for Modern Communications Science Foundation of China (Grant No. 9140C1101010601), and
the ISN Open Foundation 相似文献
9.
The electronic structure of stressed CrSi2 was calculated using the first-principle methods based on plane-wave pseudo-potential theory. The calculated results showed
that, under the uniaxial compression, the energy level of CrSi2 shifted toward high energy and its energy gap became wider with the increasing uniaxial stress, while the gap became narrower
under the negative uniaxial stress. When the negative uniaxial stress was up to −18.5 GPa, CrSi2 was converted into a direct-gap semiconductor with the band gap of 0.32 eV.
Supported by the National Natural Science Foundation of China (Grant No. 60566001), the Specialized Research Fund for the
Doctoral Program of Higher Education of China (Grant No. 20050657003), the Scientific Research Foundation for the Returned
Overseas Chinese Scholars, Ministry of Education of China (Grant No. (2005)383), the Program for the Excellent Young Talents
of Guizhou Province (Grant No. 20050528), the Specialized Nomarch Research Fund for the Excellent Science and Technology and
Education Talent’s Projects of Guizhou Province, Scientific and Technological Projects for the Returned Overseas Chinese Scholars,
the Guizhou Province (Grant No. (2004)03), and the Top Talent’s Scientific Research Project of Organization Department of
Guizhou Province 相似文献
10.
Using the first principle methods based on the plane-wave pseudo-potential theory, band structure, density of states and optical
properties of CrSi2 were studied. The calculation of band structure shows that CrSi2 is an indirect semiconductor whose band gap is 0.353 eV. Density of states is mainly composed of 3d electron of Cr and 3p
electron of Si. Dielectric function, refractive index, reflectivity, and absorption coefficient of CrSi2 are also calculated. The calculation results of optical properties are in agreement with the experiments.
Supported by the National Natural Science Foundation of China (Grant No. 60566001), the Specialized Research Fund for the
Doctoral Program of Higher Education of China (Grant No. 20050657003), the Scientific Research Foundation for the Returned
Overseas Chinese Scholars, Ministry of Education of China (Grant No. (2005)383), the Program for Excellent Young Talents of
Guizhou Province (No. 20050528), the Specialized Nomarch Research Fund for the Excellent Science and Technology and Education
Talent’s Projects of Guizhou Province, the Scientific and Technological Projects for the Returned Overseas Chinese Scholars,
Guizhou Province (Grant No. (2004)03), and the Top Talent’s Scientific Research Project of Organization Department of Guizhou
Province. 相似文献
11.
The electronic structure, densities of states and optical properties of the stable orthorhombic BaSi2 have been calculated using the first-principle density function theory and pseudopotential method. The results show that
BaSi2 is an indirect semiconductor with the band gap of 1.086 eV, the valence bands of BaSi2 are mainly composed of Si 3p, 3s and Ba 5d, and the conduction bands are mainly composed of Ba 6s, 5d as well as Si 3p. The
static dielectric function ɛ
1(0) is 11.17, the reflectivity n
0 is 3.35, and the biggest peak of the absorption coefficient is 2.15×105 cm−1.
Supported by the National Natural Science Foundation of China (Grant Nos. 60566001 and 60766002), the Specialized Research
Fund for the Doctoral Program of Higher Education of China (Grant No. 20050657003), the Scientific Research Foundation for
the Returned Overseas Chinese Scholars, Ministry of Education of China (Grant No. (2005)383), the Specialized Fund of Nomarch
for Excellent Talent of Science and Technology of Guizhou Province (Grant No. Z053114), the Scientific and Technological Projects
for the Returned Overseas of Guizhou Province (Grant No. (2004)03), and the Top Talent’s Scientific Research Project of Organization
Department of Guizhou Province (Grant No. Z053123) 相似文献
12.
YANG YuGuang WEN QiaoYan & ZHU FuChen School of Computer Beijing University of Technology Beijing China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China School of Science Beijing University of Posts Telecommunications Beijing China National Key Laboratory for Modern Communications Chengdu China 《中国科学G辑(英文版)》2007,50(3):331-338
An efficient quantum secret sharing protocol with orthogonal product states in the 33 Hilbert space is presented. The particles in the orthogonal product states form two particle sequences. One sequence is sent to Bob and the other is sent to Charlie after rearranging the particle orders. With the help of Alice, Bob and Charlie make the corresponding local measurement to obtain the information of the or- thogonal product states prepared. This protocol has many distinct features such as great capacity and high efficiency. 相似文献
13.
Through phase transformation kinetic analysis and experimental observation, the δ/γ transformation occurring in the non-equilibrium peritectic Fe-4.33at.%Ni alloys was systematically investigated. According to JMA solid-state transformation kinetic theory, the Time-Temperature-Transformation (TTT) curves of the δ/γ transformation in peritectic Fe-Ni alloy were calculated. On this basis, the physical correlation between the δ/γ transformation and the initial undercooling of melt (△T) was elucidated. The results indicate that the change of △T can alter not only the overall δ/γ transformation pathways but also the transformation fraction with respect to each transformation mechanism. 相似文献
14.
Hawking radiation can be viewed as a process of quantum tunneling near the black hole horizon. When a particle with angular
momentum L ≠ ωa tunnels across the event horizon of Kerr or Kerr-Newman black hole, the angular momentum per unit mass a should be changed. The emission rate of the massless particles under this general case is calculated, and the result is consistent
with an underlying unitary theory.
Supported by the National Natural Science Foundation of China (Grant No. 10773002) and the National Basic Research Program
of China (Grant No. 2003CB716302) 相似文献
15.
The kinetic viscosities of superheated liquids on the Gd-based bulk glass-forming alloys are measured by an oscillating viscometer
in a high vacuum atmosphere. According to the viscosity data, the parameters of superheated liquid fragility, M, are calculated. Based on the values of M in Gd-and Pr-based (cited from the literature) glass-forming alloys, we find that there is a linear correlation between M and the absolute value of mixing enthalpy, |ΔH
mix|, in an alloy system with the same base element, and the larger M, the smaller |ΔH
mix|. The alloy with larger M exhibits the larger height of energy barriers separating the minima on the potential energy landscape.
Supported by the National Basic Research Program of China (973 Program) (Grant No. 2007CB613901), the National Natural Science
Foundation of China (Grant No. 50231040), the Natural Science Foundation of Shandong Province of China (Grant No. Z2004F02),
and the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20050422024) 相似文献
16.
Recently, Yang et al. proposed a kind of quantum cryptographic schemes based on secret sharing. The main idea is drawn from the case, where any n participants who share a secret K can co-operate as K does. This process can be applied to encryption, authentication, signature and so on. Unfortunately, since there is no identity authentication of the share’s holder, these schemes inherit the limitation of secret sharing in practice. If some participants do not follow the protocol, the protocol would be a failu... 相似文献
17.
Zeng Zhang Rong Zhang ZiLi Xie Bin Liu XiangQian Xiu RuoLian Jiang Ping Han ShuLin Gu Yi Shi YouDou Zheng 《中国科学G辑(英文版)》2008,51(8):1046-1052
The surface morphology, electrical properties and optical properties of Si doped n-type GaN were investigated. The intentional
SiH4 doped GaN films were grown by metal organic chemical vapor deposition with the electron concentration varying from 3×1016 cm−3 to 5.4×1018 cm−3. The surface morphology shows that the roughness and dislocation pits increase as the mass flow rate of SiH4 increases, which indicates that the quality of GaN degrades gradually. The activation energy of Si in GaN with different
n concentrations varies from 12 to 22 meV, which may originate from the interactions of donor wave functions. The carrier transport
mechanism with increasing temperature from 100 to 420 K was concluded as the complex effect of both impurity scattering and
phonon scattering. The position of the near band edge emission peak was determined by both renormalization of the band gap
and B-M effect. The intensity variations of the yellow luminescence could be explained by the change of Ga vacancy concentration
caused by Si doping.
Supported by the National Basic Research Program of China (Grant No. 2006CB6049), the National Hi-Tech Research and Development
Program of China (Grant No. 2006AA03A142), the National Natural Science Foundation of China (Grant Nos. 60721063, 60731160628
and 60676057), the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20050284004) and the Natural
Science Foundation of Jiangsu Province of China (Grant No. BK2005210) 相似文献
18.
Deceleration of a continuous-wave (CW) molecular beam with a single quasi-CW semi-Gaussian laser beam 下载免费PDF全文
We propose a promising scheme to decelerate a CW molecular beam by using a red-detuned quasi-cw semi-Gaussian laser beam (SGB). We study the dynamical process of the deceleration for a CW deuterated ammonia (ND3) molecular beam by Monte-Carlo simulation method. Our study shows that we can obtain a ND3 molecular beam with a relative average kinetic energy loss of about 10% and a relative output molecular number of more than 90% by using a single quasi-cw SGB with a power of 1.5kW and a maximum optical well depth of 7.33mK. 相似文献
19.
A quantum secret sharing scheme between an m-party group and an n-party group is proposed using three conjugate bases. A sequence of single photons, each of which is prepared in one of the
six states, is used directly to encode classical information in the quantum secret sharing process. In this scheme, each of
all m members in group 1 chooses randomly his/her own secret key individually and independently, and directly encodes his/her respective
secret information on the states of single photons via unitary operations, then the last one sends 1/n of the resulting qubits to each member of group 2. By measuring their respective qubits, all members in group 2 share the
secret information shared by all members in group 1. It renders impossible a Trojan horse attack with a multi-photon signal,
a fake-signal attack with EPR pairs, an attack with single photons, and an attack with invisible photons. We give the upper
bounds on the average success probabilities for dishonest agent eavesdropping encryption using the fake-signal attack with
any two-particle entangled states.
Supported by the National Natural Science Foundation of China (Grant No. 10671054), the Key Project of Science and Technology
Research of Education Ministry of China (Grant No. 207011) and the Natural Science Foundation of Hebei Province, China (Grant
Nos. 07M006 and F2009000311) 相似文献
20.
GuoXiang Ai PeiXuan Sheng JinLin Du YongGuang Zheng XianDe Cai HaiTao Wu YongHui Hu Yu Hua XiaoHui Li 《中国科学G辑(英文版)》2009,52(3):376-383
This work describes the barometric altimetry as virtual constellation applied to the Chinese Area Positioning System (CAPS),
which uses the transponders of communication satellites to transfer navigation messages to users. Barometric altimetry depends
on the relationship of air pressure varying with altitude in the Earth’s atmosphere. Once the air pressure at a location is
measured the site altitude can be found. This method is able to enhance and improve the availability of three-dimensional
positioning. The difficulty is that the relation between barometric pressure and altitude is variable in different areas and
under various weather conditions. Hence, in order to obtain higher accuracy, we need to acquire the real-time air pressure
corresponding to an altimetric region’s reference height. On the other hand, the altimetry method will be applied to satellite
navigation system, but the greatest difficulty lies in how to get the real-time air pressure value at the reference height
in the broad areas overlaid by satellite navigation. We propose an innovational method to solve this problem. It is to collect
the real-time air pressures and temperatures of the 1860 known-altitude weather observatories over China and around via satellite
communication and to carry out time extrapolation forecast uniformly. To reduce data quantity, we first partition the data
and encode them and then broadcast these information via navigation message to CAPS users’ receivers. Upon the interpolations
being done in receivers, the reference air pressure and temperature at the receiver’s nearby place is derived. Lastly, combing
with the receiver-observed real air pressure and temperature, the site’s altitude can be determined. The work is presented
in the following aspects: the calculation principle, formulae, data collection, encoding, prediction, interpolation method,
navigation message transmission together with errors causes and analyses. The advantages and shortcomings of the technique
are discussed at the end.
Supported by the National Basic Research Program of China (Grant No. 2007CB815500), the National High Technology Research
and Development Program (Grant No. 2004AA105030), the Pilot Project of the Knowledge Innovation Program of the Chinese Academy
of Sciences (Grant No. KGCX1-21), and the National Natural Science Foundation of China (Grant No. 10453001) 相似文献