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On Discrete Hopf Fibrations, Grand Unification Groups, the Barnes-Wall, Leech Lattices, and Quasicrystals
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作者 Carlos Castro Perelman 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1699-1712,共14页
A discrete Hopf fibration of S15 over S8 with S7 (unit octonions) as fibers leads to a 16D Polytope P16 with 4320 vertices obtained from the convex hull of the 16D Barnes-Wall lattice Λ16. It is argued (conjectured) ... A discrete Hopf fibration of S15 over S8 with S7 (unit octonions) as fibers leads to a 16D Polytope P16 with 4320 vertices obtained from the convex hull of the 16D Barnes-Wall lattice Λ16. It is argued (conjectured) how a subsequent 2-1 mapping (projection) of P16 onto a 8D-hyperplane might furnish the 2160 vertices of the uniform 241 polytope in 8-dimensions, and such that one can capture the chain sequence of polytopes 241,231,221,211in D=8,7,6,5dimensions, leading, respectively, to the sequence of Coxeter groups E8,E7,E6,SO(10)which are putative GUT group candidates. An embedding of the E8⊕E8and E8⊕E8⊕E8lattice into the Barnes-Wall Λ16 and Leech Λ24 lattices, respectively, is explicitly shown. From the 16D lattice E8⊕E8one can generate two separate families of Elser-Sloane 4D quasicrystals (QC’s) with H4 (icosahedral) symmetry via the “cut-and-project” method from 8D to 4D in each separate E8 lattice. Therefore, one obtains in this fashion the Cartesian product of two Elser-Sloane QC’s Q×Qspanning an 8D space. Similarly, from the 24D lattice E8⊕E8⊕E8one can generate the Cartesian product of three Elser-Sloane 4D quasicrystals (QC’s) Q×Q×Qwith H4 symmetry and spanning a 12D space. 展开更多
关键词 Division Algebras Hopf Fibrations Barnes-Wall lattice Leech lattice Exceptional Lie Algebras Grand Unification QUASICRYSTALS
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Band structures of strained kagome lattices
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作者 徐露婷 杨帆 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期456-463,共8页
Materials with kagome lattices have attracted significant research attention due to their nontrivial features in energy bands.We theoretically investigate the evolution of electronic band structures of kagome lattices... Materials with kagome lattices have attracted significant research attention due to their nontrivial features in energy bands.We theoretically investigate the evolution of electronic band structures of kagome lattices in response to uniaxial strain using both a tight-binding model and an antidot model based on a periodic muffin-tin potential.It is found that the Dirac points move with applied strain.Furthermore,the flat band of unstrained kagome lattices is found to develop into a highly anisotropic shape under a stretching strain along y direction,forming a partially flat band with a region dispersionless along ky direction while dispersive along kx direction.Our results shed light on the possibility of engineering the electronic band structures of kagome materials by mechanical strain. 展开更多
关键词 kagome lattice STRAIN band structure engineering
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Rule acquisition of three-way semi-concept lattices in formal decision context
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作者 Jie Zhao Renxia Wan +1 位作者 Duoqian Miao Boyang Zhang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第2期333-347,共15页
Three-way concept analysis is an important tool for information processing,and rule acquisition is one of the research hotspots of three-way concept analysis.However,compared with three-way concept lattices,three-way ... Three-way concept analysis is an important tool for information processing,and rule acquisition is one of the research hotspots of three-way concept analysis.However,compared with three-way concept lattices,three-way semi-concept lattices have three-way operators with weaker constraints,which can generate more concepts.In this article,the problem of rule acquisition for three-way semi-concept lattices is discussed in general.The authors construct the finer relation of three-way semi-concept lattices,and propose a method of rule acquisition for three-way semi-concept lattices.The authors also discuss the set of decision rules and the relationships of decision rules among object-induced three-way semi-concept lattices,object-induced three-way concept lattices,classical concept lattices and semi-concept lattices.Finally,examples are provided to illustrate the validity of our conclusions. 展开更多
关键词 finer relation rule acquisition three-way concept analysis three-way semi-concept lattices
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Nanofabrication of nanostructure lattices:from high-quality large patterns to precise hybrid units
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作者 Rui Ma Xiaodan Zhang +2 位作者 Duncan Sutherland Vladimir Bochenkov Shikai Deng 《International Journal of Extreme Manufacturing》 CSCD 2024年第6期107-135,共29页
Sub-wavelength nanostructure lattices provide versatile platforms for light control and the basis for various novel phenomena and applications in physics, material science, chemistry, biology,and energy. The thriving ... Sub-wavelength nanostructure lattices provide versatile platforms for light control and the basis for various novel phenomena and applications in physics, material science, chemistry, biology,and energy. The thriving study of nanostructure lattices is building on the remarkable progress of nanofabrication techniques, especially for the possibility of fabricating larger-area patterns while achieving higher-quality lattices, complex shapes, and hybrid materials units. In this review, we present a comprehensive review of techniques for large-area fabrication of optical nanostructure arrays, encompassing direct writing, self-assembly, controllable deposition, and nanoimprint/print methods. Furthermore, a particular focus is made on the recent improvement of unit accuracy and diversity, leading to integrated and multifunctional structures for devices and applications. 展开更多
关键词 nanofabrication nanostructure lattices hybrid material structures metasurfaces large-area fabrication
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Three-Dimensional Printing Conformal Cooling with Structural Lattices for Plastic Injection Molding
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作者 Suping Shen Baris Burak Kanbur +1 位作者 Chenlong Wu Fei Duan 《Frontiers in Heat and Mass Transfer》 EI 2024年第2期397-415,共19页
The design of three-dimensional printing based conformal cooling channels(CCCs)in injection molding holds great significance.Compared to CCCs,conformal cooling(CC)cavity solutions show promise in delivering enhanced c... The design of three-dimensional printing based conformal cooling channels(CCCs)in injection molding holds great significance.Compared to CCCs,conformal cooling(CC)cavity solutions show promise in delivering enhanced cooling performance for plastic products,although they have been underexplored.In this research,CC cavity is designed within the mold geometry,reinforced by body-centered cubic(BCC)lattice structures to enhance mechanical strength.Three distinct BCC lattice variations have been integrated into the CC cavity:the BCC structure,BCC with cubes,and BCC with pillars.The thermal performances of the BCC lattice-added CC cavity are assessed numerically after experimental validation.To provide feasible solutions from viewpoints of thermal performances,various BCC lattice structure thicknesses are analyzed in the range of 0.8–1.2mm.Thermal simulation outcomes reveal that thicker lattice structures enhance mechanical strength but simultaneously lead to an increase in cooling time.Upon examining all the proposed CC cavity solutions supported by BCC,the cooling times range from 2.2 to 4 s,resulting in a reduction of 38.6%to 66.1%when compared to conventional straightdrilled channels.In contrast to CCCs,CC cavities have the potential to decrease the maximum temperature nonuniformity from 8.5 to 6 K.Nevertheless,the presence of lattice structures in CC cavity solutions results in an elevated pressure drop,reaching 2.8MPa,whereas the results for CCCs remain below2.1MPa. 展开更多
关键词 Conformal cooling cavity plastic injection additive manufacturing computational simulation thermal analysis lattice structure
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Nonlinear localization of ultracold atomic Fermi gas in moiré optical lattices
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作者 Xiuye Liu Jianhua Zeng 《Advanced Photonics Nexus》 2024年第3期50-57,共8页
Moirésuperlattices,a twisted functional structure crossing the periodic and nonperiodic potentials,have recently attracted great interest in multidisciplinary fields,including optics and ultracold atoms,because o... Moirésuperlattices,a twisted functional structure crossing the periodic and nonperiodic potentials,have recently attracted great interest in multidisciplinary fields,including optics and ultracold atoms,because of their unique band structures,physical properties,and potential implications.Driven by recent experiments on quantum phenomena of bosonic gases,the atomic Bose–Einstein condensates in moiréoptical lattices,by which other quantum gases such as ultracold fermionic atoms are trapped,could be readily achieved in ultracold atom laboratories,whereas the associated nonlinear localization mechanism remains unexploited.Here,we report the nonlinear localization theory of ultracold atomic Fermi gases in two-dimensional moiréoptical lattices.The linear Bloch-wave spectrum of such a twisted structure exhibits rich nontrivial flat bands,which are separated by different finite bandgaps wherein the existence,properties,and dynamics of localized superfluid Fermi gas structures of two types,gap solitons and gap vortices(topological modes)with vortex charge S¼1,are studied numerically.Our results demonstrate the wide stability regions and robustness of these localized structures,opening up a new avenue for studying soliton physics and moiréphysics in ultracold atoms beyond bosonic gases. 展开更多
关键词 moiréoptical lattices gap solitons ultracold Fermi gases density-functional equation.
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基于Lattice LSTM-Cascade结构盗窃罪案由的命名实体识别算法
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作者 潘鑫宇 陈亮 王珺琳 《通信与信息技术》 2025年第1期118-122,共5页
通过信息抽取技术进行法律文书数据的结构化,是推进人工智能在司法领域应用的关键性工作,尤其命名实体识别作为信息抽取的基础任务,将直接影响对案情信息提取的完整性与精确性。由于法律文书词语具有单义性、针对性和规范性且细粒度高... 通过信息抽取技术进行法律文书数据的结构化,是推进人工智能在司法领域应用的关键性工作,尤其命名实体识别作为信息抽取的基础任务,将直接影响对案情信息提取的完整性与精确性。由于法律文书词语具有单义性、针对性和规范性且细粒度高的特点,通过Lattice LSTM实现字词特征融合输入,深度挖掘文书的语义信息;由于法律文书的精细化描述,需要高细粒度的实体类别,导致实体类别增加,通过采用Cascade结构构建了多任务NER模型框架,实现了实体识别与实体类别分类的联合处理,在识别准确率提高的同时减少模型的训练时间。消融实验结果表明:字词联合输入相较于基线模型F1值提高了1.59%;加入Cascade结构相较于基线模型每轮训练的时间减少4分钟。对比实验结果表明:该模型的实验结果的三项指标为88.85%、90.27%和89.55%,均高于其他对比模型。因此,该模型在法律文书命名实体识别中具有有效性及准确性。 展开更多
关键词 法律文书 命名实体识别 lattice LSTM 多任务NER框架
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Statistical segmentation model on lattices
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作者 俞璐 谢钧 吴乐南 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期10-14,共5页
To reduce the difficulty of implementation and shorten the runtime of the traditional Kim-Fisher model, an entirely discrete Kim-Fisher-like model on lattices is proposed. The discrete model is directly built on the l... To reduce the difficulty of implementation and shorten the runtime of the traditional Kim-Fisher model, an entirely discrete Kim-Fisher-like model on lattices is proposed. The discrete model is directly built on the lattices, and the greedy algorithm is used in the implementation to continually decrease the energy function. First, regarding the gray values in images as discrete-valued random variables makes it possible to make a much simpler estimation of conditional entropy. Secondly, a uniform method within the level set framework for two-phase and multiphase segmentations without extension is presented. Finally, a more accurate approximation to the curve length on lattices with multi-labels is proposed. The experimental results show that, compared with the continuous Kim-Fisher model, the proposed model can obtain comparative results, while the implementation is much simpler and the runtime is dramatically reduced. 展开更多
关键词 image segmentation curve evolution conditional entropy latticE labelling problem
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The Classification of Positive Definite Unimodular Lattices Over Z[(1+21^(1/2))/2]
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作者 王瑞卿 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期87-93,共7页
In this paper, the author applies adjacent lattice method and Siegel mass formula to determine the classes of positive definite unimodular lattices of rank 4 over Z , and obtains that the class number of unit genus ... In this paper, the author applies adjacent lattice method and Siegel mass formula to determine the classes of positive definite unimodular lattices of rank 4 over Z , and obtains that the class number of unit genus gen( I 4 ) is nine and the class number of even unimodular lattices is three, and also gives the representative lattices of each class. 展开更多
关键词 positive definite unimodular adjacent lattice class number Siegel mass formula orthogonal group
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The Classification of Positive Definite Unimodular Lattices Over Z[(1+211/2)/2] 被引量:4
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作者 王瑞卿 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期87-93,共页
In this paper, the author applies adjacent lattice method and Siegel mass formula to determine the classes of positive definite unimodular lattices of rank 4 over Z , and obtains that the class number of unit genus ... In this paper, the author applies adjacent lattice method and Siegel mass formula to determine the classes of positive definite unimodular lattices of rank 4 over Z , and obtains that the class number of unit genus gen( I 4 ) is nine and the class number of even unimodular lattices is three, and also gives the representative lattices of each class. 展开更多
关键词 positive definite unimodular adjacent lattice class number Siegel mass formula orthogonal group
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GENERALIZATIONS AND CARTESIAN CLOSED SUBCATEGORIES OF SEMICONTINUOUS LATTICES 被引量:4
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作者 李庆国 伍秀华 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1366-1374,共9页
In this article, the authors mainly study how to obtain new semicontinuous lattices from the given semicontinuous lattices and discuss the conditions under which the image of a semicontinuous projection operator is al... In this article, the authors mainly study how to obtain new semicontinuous lattices from the given semicontinuous lattices and discuss the conditions under which the image of a semicontinuous projection operator is also semicontinuous. Moreover, the authors investigate the relation between semicontinuous lattices and completely distributive lattices. Finally, it is proved that the strongly semicontinuous lattice category is a Cartesian closed category. 展开更多
关键词 semicontinuous lattices strongly semicontinuous lattices semicontinuous mapping HEREDITARY function space Cartesian closed category
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Stereolithographic 3D Printing-Based Hierarchically Cellular Lattices for High-Performance Quasi-Solid Supercapacitor 被引量:6
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作者 Jianzhe Xue Libo Gao +4 位作者 Xinkang Hu Ke Cao Wenzhao Zhou Weidong Wang Yang Lu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2019年第3期165-177,共13页
3D printing-based supercapacitors have been extensively explored,yet the rigid rheological requirement for corresponding ink preparation significantly limits the manufacturing of true 3D architecture in achieving supe... 3D printing-based supercapacitors have been extensively explored,yet the rigid rheological requirement for corresponding ink preparation significantly limits the manufacturing of true 3D architecture in achieving superior energy storage.We proposed the stereolithographic technique to fabricate the metallic composite lattices with octet-truss arrangement by using electroless plating and engineering the 3D hierarchically porous graphene onto the scaffolds to build the hierarchically cellular lattices in quasi-solid supercapacitor application.The supercapacitor device that is composed of composite lattices span several pore size orders from nm to mm holds promising behavior on the areal capacitance(57.75 mF cm-2),rate capability(70% retention,2-40 mA cm-2),and long lifespan(96% after 5000 cycles),as well as superior energy density of 0.008 mWh cm-2,which are comparable to the state-of-the-art carbon-based supercapacitor.By synergistically combining this facile stereolithographic 3D printing technology with the hierarchically porous graphene architecture,we provide a novel route of manufacturing energy storage device as well as new insight into building other high-performance functional electronics. 展开更多
关键词 3D PRINTING lattices Graphene SUPERCAPACITOR Porous structure STEREOLITHOGRAPHY
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Digital image encryption with chaotic map lattices 被引量:8
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作者 孙福艳 吕宗旺 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期132-138,共7页
This paper proposes a secure approach for encryption and decryption of digital images with chaotic map lattices. In the proposed encryption process, eight different types of operations are used to encrypt the pixels o... This paper proposes a secure approach for encryption and decryption of digital images with chaotic map lattices. In the proposed encryption process, eight different types of operations are used to encrypt the pixels of an image and one of them will be used for particular pixels decided by the outcome of the chaotic map lattices. To make the cipher more robust against any attacks, the secret key is modified after encrypting each block of sixteen pixels of the image. The experimental results and security analysis show that the proposed image encryption scheme achieves high security and efficiency. 展开更多
关键词 image encryption image decryption chaotic map lattice CRYPTOGRAPHY spatiotemporal chaotic system
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Tolerance of edge cascades with coupled map lattices methods 被引量:7
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作者 崔迪 高自友 郑建风 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第3期992-996,共5页
This paper studies the cascading failure on random networks and scale-free networks by introducing the tolerance parameter of edge based on the coupled map lattices methods. The whole work focuses on investigating som... This paper studies the cascading failure on random networks and scale-free networks by introducing the tolerance parameter of edge based on the coupled map lattices methods. The whole work focuses on investigating some indices including the number of failed edges, dynamic edge tolerance capacity and the perturbation of edge. In general, it assumes that the perturbation is attributed to the normal distribution in adopted simulations. By investigating the effectiveness of edge tolerance in scale-free and random networks, it finds that the larger tolerance parameter λ can more efficiently delay the cascading failure process for scale-free networks than random networks. These results indicate that the cascading failure process can be effectively controlled by increasing the tolerance parameter λ. Moreover, the simulations also show that, larger variance of perturbation can easily trigger the cascading failures than the smaller one. This study may be useful for evaluating efficiency of whole traffic systems, and for alleviating cascading failure in such systems. 展开更多
关键词 cascading failures coupled map lattice methods TOLERANCE
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Cascades with coupled map lattices in preferential attachment community networks 被引量:6
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作者 崔迪 高自友 赵小梅 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第5期1703-1708,共6页
In this paper, cascading failure is studied by coupled map lattice (CML) methods in preferential attachment community networks. It is found that external perturbation R is increasing with modularity Q growing by sim... In this paper, cascading failure is studied by coupled map lattice (CML) methods in preferential attachment community networks. It is found that external perturbation R is increasing with modularity Q growing by simulation. In particular, the large modularity Q can hold off the cascading failure dynamic process in community networks. Furthermore, different attack strategies also greatly affect the cascading failure dynamic process. It is particularly significant to control cascading failure process in real community networks. 展开更多
关键词 community networks MODULARITY coupled map lattices cascading failure
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Vortex solitons in the semi-infinite gap of optically induced periodic lattices 被引量:4
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作者 王建东 纪红 刘普生 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期286-291,共6页
Vortex solitons with a ring vortex core residing in a single lattice site in the semi-infinite gap of square optical lattices are reported. These solitons are no longer bound states of the Bloch-wave unit (Bloch-wave... Vortex solitons with a ring vortex core residing in a single lattice site in the semi-infinite gap of square optical lattices are reported. These solitons are no longer bound states of the Bloch-wave unit (Bloch-wave distribution in one lattice site) at the band edge of the periodic lattice, and consequently they do not bifurcate from the corresponding band edge. For saturable nonlinearity, one family of such solitons is found, and its existing curve forms a closed loop, which is very surprising. For Kerr nonlinearity, two families of such vortex solitons are found. 展开更多
关键词 vortex soliton Bloch band gap nonlinear periodic lattice
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New Identity Based Proxy Re-Encryption Scheme from Lattices 被引量:2
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作者 Liqiang Wu Xiaoyuan Yang +1 位作者 Minqing Zhang Longfei Liu 《China Communications》 SCIE CSCD 2019年第10期174-190,共17页
Identity-Based Proxy Re-Encryption (IB-PRE) allows a semi-trusted proxy to convert the ciphertext encrypted under Alice’s identity into Bob’s ciphertext of the same message without leaking plaintext. Lattice-based c... Identity-Based Proxy Re-Encryption (IB-PRE) allows a semi-trusted proxy to convert the ciphertext encrypted under Alice’s identity into Bob’s ciphertext of the same message without leaking plaintext. Lattice-based cryptography enjoys potential resistance to quantum analysis and low computational complexity. A multi-hop and unidirectional IB-PRE from lattices is presented. We split the functions of decryption and ciphertext transformation separately, and design the double private keys mechanism, where two keys are generated for each user, one key is used to decrypt the ciphertext by Pre-Image Sampling technique, and the other is used to generate the re-encryption key by Bonsai Trees technique. The generation of the re-encryption key is non-interactive and collusion resistant. Moreover, its IND-sID-CPA security over the decisional Learning With Errors (LWE) assumption under the standard model is proved. Compared with some previous IBPRE schemes from Bilinear Pairings, the format of transformed ciphertext in our scheme remains unchanged, furthermore, it can also resist quantum analysis. Compared with some existing IB-PRE schemes from lattices with similar properties, the space of the message in our scheme is a vector of length l and the encryption process remains a lower encryption blowup factor. At last, a proof-of-concept implementation is provided. 展开更多
关键词 IB-PRE lattices BONSAI trees COLLUSION RESISTANCE
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ON GENERALIZED BUFFON NEEDLE PROBLEM FOR LATTICES 被引量:3
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作者 谢凤繁 李德宜 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期303-308,共6页
Two new concepts, the generalized support function and restricted chord function, both referring to a convex set, were introduced in [1]. General formulae to yield the kinematic measure of a segment of fixed length in... Two new concepts, the generalized support function and restricted chord function, both referring to a convex set, were introduced in [1]. General formulae to yield the kinematic measure of a segment of fixed length in a convex set were established based on these concepts. In this article , using the partial intersection method, we consider the generalized Buffon problem for three kinds of lattices. We determine the probability of intersection of a body test needle of length l, l a. 展开更多
关键词 Geometric probability integral geometry Buffon problem lattice of regions kinematic measure
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Partial and complete periodic synchronization in coupled discontinuous map lattices 被引量:2
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作者 杨科利 陈会云 +2 位作者 杜伟伟 金涛 屈世显 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期331-336,共6页
The partial and complete periodic synchronization in coupled discontinuous map lattices consisting of both discon- tinuous and non-invertible maps are discussed. We classify three typical types of periodic synchroniza... The partial and complete periodic synchronization in coupled discontinuous map lattices consisting of both discon- tinuous and non-invertible maps are discussed. We classify three typical types of periodic synchronization states, which give rise to different spatiotemporal patterns including static partial periodic synchronization, dynamically periodic syn- chronization, and complete periodic synchronization patterns. A special prelude dynamics of partial and complete periodic synchronization motion, which is shown by five separated concave curves in the time series plots of the order parameters, is observed. The detailed analysis shows that the special prelude dynamics is induced by the competition between two synchronized clusters, and the analytical expression for the corresponding order parameter is obtained. 展开更多
关键词 discontinuous map coupled map lattices periodic synchronization prelude dynamics
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Cryptanalysis and improvement of a digital image encryption method with chaotic map lattices 被引量:2
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作者 王兴元 刘林涛 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期198-202,共5页
A digital image encryption scheme using chaotic map lattices has been proposed recently. In this paper, two fatal flaws of the cryptosystem are pointed out. According to these two drawbacks, cryptanalysts could recove... A digital image encryption scheme using chaotic map lattices has been proposed recently. In this paper, two fatal flaws of the cryptosystem are pointed out. According to these two drawbacks, cryptanalysts could recover the plaintext by applying the chosen plaintext attack. Therefore, the proposed cryptosystem is not secure enough to be used in the image transmission system. Experimental results show the feasibility of the attack. As a result, we make some improvements to the encryption scheme, which can completely resist our chosen plaintext attack. 展开更多
关键词 CRYPTANALYSIS chosen plaintext attack image encryption chaotic map lattice
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