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几类MDS码和NMDS码的构造
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作者 杜小妮 薛婧 +1 位作者 乔兴斌 赵紫薇 《西北师范大学学报(自然科学版)》 2026年第1期41-48,共8页
MDS码是参数达到Singleton界的最优线性码,广泛应用于分布式存储系统和随机误差信道等领域.与之密切相关的NMDS码在保持近似纠错性能的同时,可以显著降低编译码复杂度,因此成为编码理论研究的热点之一.通过选取有限域F_(q^(2))(其中q为... MDS码是参数达到Singleton界的最优线性码,广泛应用于分布式存储系统和随机误差信道等领域.与之密切相关的NMDS码在保持近似纠错性能的同时,可以显著降低编译码复杂度,因此成为编码理论研究的热点之一.通过选取有限域F_(q^(2))(其中q为2的幂次)上单位圆盘中的元素来构造矩阵,并在其中添加一个列向量,将其作为生成矩阵构造了F_(q^(2))上几类码长为(q+2)的MDS码和NMDS码,研究了NMDS码的重量计数器;选取F_(q^(t))(t≥1为整数)中含有l(4<l≤q^(t))个元素的集合构造了码长为l的MDS码.研究发现,构造的MDS码均为Griesmer码,NMDS码均为near Griesmer码;码本表明,本文构造的所有码均为新码. 展开更多
关键词 MDS码 NMDS码 重量计数器 Griesmer界
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Simultaneous enumeration of diatom,protozoa and meiobenthos from marine sediments using Ludox-QPS method 被引量:10
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作者 杜永芬 徐奎栋 类彦立 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第4期775-783,共9页
The Ludox-QPS method is a newly developed technique,which combines the Ludox HS 40 density centrifugation and quantitative protargol stain,to enumerate marine ciliates with good taxonomic resolution.We tested the meth... The Ludox-QPS method is a newly developed technique,which combines the Ludox HS 40 density centrifugation and quantitative protargol stain,to enumerate marine ciliates with good taxonomic resolution.We tested the method for simultaneous enumeration of diatoms,protozoa and meiobenthos and compared its extraction efficiency for meiobenthos with that of the routine Ludox-TM centrifugation and a modified protocol using Ludox HS 40.We conducted the evaluation with a sample size of 8.3 ml each from sandy,muddy-sand and muddy sediments collected from the intertidal area of the Yellow Sea in summer 2006 and spring 2007.The Ludox-QPS method not only produced high extraction efficiencies of 97±1.3% for diatoms and 97.6±0.8% for ciliates,indicating a reliable enumeration for eukaryotic microbenthos,but also produced excellent extraction efficiencies of on average 97.3% for total meiobenthos,97.9% for nematodes and 97.8% for copepods from sands,muddy sands and mud.By contrast,the routine Ludox-TM centrifugation obtained only about 74% of total meiobenthos abundance with one extraction cycle,and the modified Ludox HS 40 centrifugation yielded on average 93% of total meiobenthos:89.4±2.0% from sands,93±4.1% from muddy sands and 97.1±3.0% from mud.Apart from the sediment type,sample volume was another important factor affecting the extraction efficiency for meiobenthos.The extraction rate was increased to about 96.4% when using the same modified Ludox centrifugation for a 4 ml sediment sample.Besides the excellent extraction efficiency,the Ludox-QPS method obtained higher abundances of meiobenthos,in particular nematodes,than the routine Ludox centrifugation,which frequently resulted in an uncertain loss of small meiobenthos during the sieving process.Statistical analyses demonstrated that there were no significant differences between the meiobenthos communities revealed by the Ludox-QPS method and the modified Ludox HS 40 centrifugation,showing the high efficiency of the Ludox-QPS method for simultaneous enumeration of diatom,protozoa and meiobenthos.Moreover,the comparatively high taxonomic resolution of the method,especially for diatoms and ciliates,makes it feasible to investigate microbial ecology at community level. 展开更多
关键词 enumeration extraction MEIOBENTHOS microbenthos Ludox HS 40 centrifugation quantitative protargol stain
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Modified physiological and operative score for the enumeration of mortality and morbidity risk assessment model in general surgery 被引量:10
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作者 Lian-An Ding Li-Qun Sun +2 位作者 Shuang-Xi Chen Lin-Lin Qu Dong-Fang Xie 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第38期5090-5095,共6页
AIM: To establish a scoring system for predicting the incidence of postoperative complications and mortality in general surgery based on the physiological and operative severity score for the enumeration of mortality ... AIM: To establish a scoring system for predicting the incidence of postoperative complications and mortality in general surgery based on the physiological and operative severity score for the enumeration of mortality and morbidity (POSSUM), and to evaluate its efficacy. METHODS: Eighty-four patients with postoperative complications or death and 172 patients without postoperative complications, who underwent surgery in our department during the previous 2 years, were retrospectively analyzed by logistic regression. Fifteen indexes were investigated including age, cardiovascular function, respiratory function, blood test results, endocrine function, central nervous system function, hepatic function, renal function, nutritional status, extent of operative trauma, and course of anesthesia. Modified POSSUM (M-POSSUM) was developed using significant risk factors with its efficacy evaluated. RESULTS: The significant risk factors were found to be age, cardiovascular function, respiratory function, hepatic function, renal function, blood test results, endocrine function, nutritional status, duration of operation, intraoperative blood loss, and course of anesthesia. These factors were all included in the scoring system. There were significant differences in the scores between the patients with and without postoperative complications, between the patients died and survived with complications, and between the patients died and survived without complications. The receiver operating characteristic curves showed that the M-POSSUM could accurately predict postoperative complications and mortality.CONCLUSION: M-POSSUM correlates well with postoperative complications and mortality, and is more accurate than POSSUM. 展开更多
关键词 Physiological and operative severity score for the enumeration of mortality and morbidity Postoperative morbidity MORTALITY Preoperative assessment General surgery Critical illness
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Machine learning for enumeration of cell colony forming units 被引量:1
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作者 Louis Zhang 《Visual Computing for Industry,Biomedicine,and Art》 EI 2022年第1期315-322,共8页
As one of the most widely used assays in biological research,an enumeration of the bacterial cell colonies is an important but time-consuming and labor-intensive process.To speed up the colony counting,a machine learn... As one of the most widely used assays in biological research,an enumeration of the bacterial cell colonies is an important but time-consuming and labor-intensive process.To speed up the colony counting,a machine learning method is presented for counting the colony forming units(CFUs),which is referred to as CFUCounter.This cellcounting program processes digital images and segments bacterial colonies.The algorithm combines unsupervised machine learning,iterative adaptive thresholding,and local-minima-based watershed segmentation to enable an accurate and robust cell counting.Compared to a manual counting method,CFUCounter supports color-based CFU classification,allows plates containing heterologous colonies to be counted individually,and demonstrates overall performance(slope 0.996,SD 0.013,95%CI:0.97–1.02,p value<1e-11,r=0.999)indistinguishable from the gold standard of point-and-click counting.This CFUCounter application is open-source and easy to use as a unique addition to the arsenal of colony-counting tools. 展开更多
关键词 Colony forming unit enumeration Image analysis Blue/white screen Colony count
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A NEW COMPLEX SPHERE DETECTOR WITH SE ENUMERATION 被引量:1
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作者 Yao Heng Jian Haifang Shi Yin 《Journal of Electronics(China)》 2012年第3期190-196,共7页
Multiple-Input Multiple-Output (MIMO) techniques are promising in wireless communication systems for its high spectral efficiency. Sphere Detector (SD) is favoured in MIMO detection to achieve Maximum-Likelihood (ML) ... Multiple-Input Multiple-Output (MIMO) techniques are promising in wireless communication systems for its high spectral efficiency. Sphere Detector (SD) is favoured in MIMO detection to achieve Maximum-Likelihood (ML) performance. In this paper, we proposed a new SD method for MIMO-Orthogonal Frequency Division Multiplexing (OFDM) systems based on IEEE802.11n, which uses Singular Value Decomposition (SVD) in complex domain to reduce the computation complexity. Furthermore, a new Schnorr-Euchner (SE) enumeration algorithm is also discussed in detail. The computer simulation result shows that the computational complexity and the number of visited nodes can be reduced significantly compared with conventional SD detectors with the same Bit Error Rate (BER) performance. 展开更多
关键词 Multiple-Input Multiple-Output (MIMO) Singular Value Decomposition (SVD) Sphere Detector (SD) Complex SD Schnorr-Euchner (SE) enumeration
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AN EXACT ENUMERATION STUDY ON ADSORPTION TRANSITION OF A TETHERED CHAIN AT AN ADSORBING SURFACE
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作者 陆文琴 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第2期209-217,共9页
The number of configurations, c(n, m), of a single chain with length n attached to a flat surface with m monomers contacting the surface is exactly enumerated. A fimction of c(n, m) about m and n is obtained. From... The number of configurations, c(n, m), of a single chain with length n attached to a flat surface with m monomers contacting the surface is exactly enumerated. A fimction of c(n, m) about m and n is obtained. From the function, a scaling law for mean energy of chain is derived, and we estimate the critical point εc = 0.276 and the crossover exponent φ = 0.5. The free energy difference between tethered chain and free chain in dilute solution is also studied, which shows the critical adsorption point is about 0.272 for infinite long chain with φ= 0.5. 展开更多
关键词 Critical point Exact enumeration Adsorption transition Polymer chain.
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Assessing edge-coupled interdependent network disintegration via rank aggregation and elite enumeration
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作者 李咏徽 刘三阳 白艺光 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期650-659,共10页
The disintegration of networks is a widely researched topic with significant applications in fields such as counterterrorism and infectious disease control. While the traditional approaches for achieving network disin... The disintegration of networks is a widely researched topic with significant applications in fields such as counterterrorism and infectious disease control. While the traditional approaches for achieving network disintegration involve identifying critical sets of nodes or edges, limited research has been carried out on edge-based disintegration strategies. We propose a novel algorithm, i.e., a rank aggregation elite enumeration algorithm based on edge-coupled networks(RAEEC),which aims to implement tiling for edge-coupled networks by finding important sets of edges in the network while balancing effectiveness and efficiency. Our algorithm is based on a two-layer edge-coupled network model with one-to-one links, and utilizes three advanced edge importance metrics to rank the edges separately. A comprehensive ranking of edges is obtained using a rank aggregation approach proposed in this study. The top few edges from the ranking set obtained by RAEEC are then used to generate an enumeration set, which is continuously iteratively updated to identify the set of elite attack edges.We conduct extensive experiments on synthetic networks to evaluate the performance of our proposed method, and the results indicate that RAEEC achieves a satisfactory balance between efficiency and effectiveness. Our approach represents a significant contribution to the field of network disintegration, particularly for edge-based strategies. 展开更多
关键词 edged-coupled rank aggregation interdependent networks elite enumeration
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ON THE CONSTRUCTION AND ENUMERATION OF HAMILTONIAN GRAPHS
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作者 胡冠章 李岷珊 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1993年第1期25-31,共7页
In this paper we give a formula for enumerating the equivalent classes of orderly labeled Hamiltonian graphs under group D. and two algorithms for constructing these equivalent classes and all nonisomorphic Hamiltonia... In this paper we give a formula for enumerating the equivalent classes of orderly labeled Hamiltonian graphs under group D. and two algorithms for constructing these equivalent classes and all nonisomorphic Hamiltonian graphs. Some computational results obtained by microcomputers are listed. 展开更多
关键词 Hamiltonian Graph Formula for Enumerating Algorithm.
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Detection of dengue NS1 antigen,alongside IgM plus IgG and concurrent platelet enumeration during an outbreak
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作者 Subhash C Arya Nirmala Agarwal Satish C Parikh 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第8期672-672,共1页
During the late incubation period or initial phase of dengue virus infection,laboratory confirmation is through viral isolation in cell culture and/or molecular investigations, or immunofluorescence,or immunohistochem... During the late incubation period or initial phase of dengue virus infection,laboratory confirmation is through viral isolation in cell culture and/or molecular investigations, or immunofluorescence,or immunohistochemistry[1].The dengue virus non-structural antigen NSl that would develop before the appearance of dengue IgM and/or IgG is emerging as a suitable option for dengue diagnosis[2].Platelet therapy is a standard clinical practice for dengue patients with severe thrombocytopenia[3].However,during introductory screening,platelet count is not being done in many cases. This results in delays of platelet therapy. In the course of the current(2010) spurt of dengue in New Delhi[4],simultaneous screening for NSl,IgM and IgG and platelet enumeration has been introduced at the 展开更多
关键词 IGM IGG Detection of dengue NS1 antigen alongside IgM plus IgG and concurrent platelet enumeration during an outbreak NS
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ENUMERATION OF ISOMERS OF SUBSTITUTED CROWN ETHERS
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作者 Shi Jun YU Department of Chemistry,Liaoning Normal University,Dalian,116022 Jian Ji WANG Department of Chemistry,Inner Mongolia Normal University,Huhehaote,010022 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第9期793-794,共2页
The graphtheory method is used to enumerate the numbers of constitutions, configurations,chiral and achiral configurations of substituted crown ethers.The numerical results are tabulated.
关键词 WANG enumeration OF ISOMERS OF SUBSTITUTED CROWN ETHERS
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Comparison of procedure for fecal colif orm enumeration in coastal waters
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作者 Ni Chunzhi, Zeng Huoshui, Yao Ruimei Liang ZiyuanThird Institute of Ocemography, State .Oceanic Ademiaistration, Xiamen, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第1期139-143,共5页
INTRODUCTION Fecal coliform has been used as an indicator of water pollution for about a century. Recently, Standrige et al (1981), Reasoner et al (1979) and Pagel et al. (1982) improved, with good results, the bioass... INTRODUCTION Fecal coliform has been used as an indicator of water pollution for about a century. Recently, Standrige et al (1981), Reasoner et al (1979) and Pagel et al. (1982) improved, with good results, the bioassy methods for fecal coliform in drinking water and waste water. To provide a method appli- 展开更多
关键词 PR Comparison of procedure for fecal colif orm enumeration in coastal waters
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Enumeration of Stereoisomers of Chiral and Achiral Derivatives of Monocyclic Cycloalkanes Having Heteromorphous Alkyl Substituents with Distinct Length <i>k</i>
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作者 Alphonse Emadak Ibrahim Mbouombouo Ndassa +2 位作者 Beauregard Thomas Makon Issofa Patouossa Robert Martin Nemba 《Computational Chemistry》 2019年第3期72-93,共22页
A combinatorial method based on the determination of the averaged weight of permutations controlling the chirality/achirality fittingness of 2n substitution sites of the monocyclic cycloalkane allows to obtain general... A combinatorial method based on the determination of the averaged weight of permutations controlling the chirality/achirality fittingness of 2n substitution sites of the monocyclic cycloalkane allows to obtain generalized functional equations for direct enumeration of enantiomers pairs and achiral skeletons of any derivatives of monocyclic cycloalkanes having heteromorphic alkyl substituents with the distinct length k with the empirical formula , wherein at least two alkyl groups??of the distinct size ?each. ?is the number of alkyl radicals ?of the system??verifying the relation . The integer sequences of enantiomer pairs and achiral skeletons are given for substituted derivatives of monocyclic cycloalkane for n = 3, 4 and k = 3, 4, 5. The composite stereoisomerism of this particular compound is also highlighted. 展开更多
关键词 enumeration STEREOISOMER Chirality Achirality Monocyclic CYCLOALKANE Order of ALKYL Trees Polyalkylation
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On the Pólya Enumeration Theorem
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作者 L. G. FEL 《Intelligent Information Management》 2009年第3期172-173,共2页
Simple formulas for the number of different cyclic and dihedral necklaces containing nj beads of the j-th color, and , are derived, using the Pólya enumeration theorem.
关键词 PERMUTATIONS and CYCLIC INVARIANCE cycle index Pólya enumeration THEOREM
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Enumeration,Genetic Characterization and Antimicrobial Susceptibility of Lactobacillus and Streptococcus Isolates from Retail Yoghurt in Beijing,China
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作者 DONG Yin Ping CHEN Qian +1 位作者 CUI Sheng Hui LI Feng Qin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第9期740-748,共9页
Lactic acid bacteria (LAB) are widely used in food industries. Correct identification and safety evaluation of these bacteria at the species even strain level should take considerations into account. In this study, ... Lactic acid bacteria (LAB) are widely used in food industries. Correct identification and safety evaluation of these bacteria at the species even strain level should take considerations into account. In this study, the LAB were recovered from yoghurt and characterized phenotypically and genetically. Fifty-two isolates of LAB from 31 yoghurt samples were cultured and grouped into 6 species including Luctobucillus bulguricus (24 isolates), Streptococcus thermophilus (15 isolates), L. ucidophilus (7 isolates), L. porucusei/cusei (3 isolates), L. delbrueckii (2 isolates), and L. fermentum (1 isolate), based on their Gram-staining, colony morphology and biochemical properties. 展开更多
关键词 enumeration Genetic Characterization and Antimicrobial Susceptibility of Lactobacillus and Streptococcus Isolates from Retail Yoghurt in Beijing China PFGE
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Combinatorial Interpretation of Raney Numbers and Tree Enumerations
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作者 Chin Hee Pah Mohamed Ridza Wahiddin 《Open Journal of Discrete Mathematics》 2015年第1期1-9,共9页
A new combinatorial interpretation of Raney numbers is proposed. We apply this combinatorial interpretation to solve several tree enumeration counting problems. Further a generalized Catalan triangle is introduced and... A new combinatorial interpretation of Raney numbers is proposed. We apply this combinatorial interpretation to solve several tree enumeration counting problems. Further a generalized Catalan triangle is introduced and some of its properties are proved. 展开更多
关键词 RANEY NUMBERS Fuss-Catalan NUMBERS Tree enumeration Network
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Enumeration Order Equivalence in Rational Numbers
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作者 Saeed Asaeedi Farzad Didehvar Aliakbar Safilian 《Computer Technology and Application》 2013年第11期615-619,共5页
The enumeration of elements of c.e. sets in the theory of computability and computational complexity has already been investigated. However, the order of this enumeration has received less attention. The enumeration o... The enumeration of elements of c.e. sets in the theory of computability and computational complexity has already been investigated. However, the order of this enumeration has received less attention. The enumeration orders of elements of c.e. sets by means of Turing machines on natural numbers are investigated. In this paper, we consider the enumeration orders of elements of c.e. sets on rational numbers. We present enumeration order reducibility and enumeration order equivalence on rational numbers and propose some lemmas and theorems on these concepts. Also, we show that the theories here hold for Rc and we could repeat the same theories in this domain, in a same way. 展开更多
关键词 Turing machine LISTINGS enumeration order reducibility enumeration order equivalence
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Chromatic Enumeration for Singular Maps on the Klein Bottle
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作者 李赵祥 刘彦佩 《Northeastern Mathematical Journal》 CSCD 2002年第4期313-318,共6页
A map is singular if each edge is on the same face on a surface (i.e., it has only one face on a surface). In this paper we present the chromatic enumeration for rooted singular maps on the Klein bottle.
关键词 singular map SURFACE chromatic enumeration
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Finite Enumeration, Infinite Thinking——Discussion on Enumeration Strategies in Primary School Mathematics
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作者 GONGLi 《外文科技期刊数据库(文摘版)教育科学》 2022年第3期090-093,共4页
The essence of enumerating strategies in mathematics is to list all possible situations according to a certain order or law. Proper enumeration can help us to list all the situations in "no repetition, no omissio... The essence of enumerating strategies in mathematics is to list all possible situations according to a certain order or law. Proper enumeration can help us to list all the situations in "no repetition, no omission". The limited list brings us endless thinking. 展开更多
关键词 enumeration strategy non-repetition not missing
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改进的6轮Square算法中间相遇攻击
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作者 何峰 董晓丽 韦永壮 《计算机技术与发展》 2025年第2期63-69,共7页
Square分组密码算法是由Daemen等人设计,并在1997年快速软件加密(FSE)国际会议上首次公布。该密码算法基于SPN(Substitution-Permutation Network)结构,其分组长度和密钥长度均为128比特;具有设计新颖、实现高效等优点,也是高级加密标准... Square分组密码算法是由Daemen等人设计,并在1997年快速软件加密(FSE)国际会议上首次公布。该密码算法基于SPN(Substitution-Permutation Network)结构,其分组长度和密钥长度均为128比特;具有设计新颖、实现高效等优点,也是高级加密标准(AES)算法的前身,在密码学界备受关注。中间相遇攻击作为分组密码算法的重要分析方法之一,如何研究Square算法抵抗中间相遇攻击一直是业内讨论的热点问题。该文基于Square算法的结构特点和截断差分特征,利用差分枚举技术,构造了一个3.5轮中间相遇区分器。通过密钥桥技术及Square算法的密钥编排特点,推演出了主密钥与子密钥之间的部分线性关系。由此,将3.5轮区分器向前扩展1轮,向后扩展1.5轮,实现了对6轮Square算法的中间相遇攻击。该攻击所需数据复杂度为2105个选择明文,时间复杂度为2105次6轮加密,存储复杂度为285个分组。与已有攻击结果相比,新的攻击有效地降低了所需的数据复杂度、时间复杂度和存储复杂度。 展开更多
关键词 分组密码 Square算法 中间相遇攻击 差分枚举技术 密钥桥技术
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地理标志反不正当竞争法保护的正当性及进路
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作者 孙智 毛陈武 《兴义民族师范学院学报》 2025年第1期50-56,共7页
我国地理标志资源丰富,潜在商业和文化价值十分突出,加强地理标志保护意义重大。从法理上讲,加强地理标志保护并不只是专门法和商标法的“专有领地”,反不正当竞争法对地理标志保护同样具有正当性和必要性;从相关国际规则和域外实践来... 我国地理标志资源丰富,潜在商业和文化价值十分突出,加强地理标志保护意义重大。从法理上讲,加强地理标志保护并不只是专门法和商标法的“专有领地”,反不正当竞争法对地理标志保护同样具有正当性和必要性;从相关国际规则和域外实践来看还具有现实可行性。反不正当竞争法虽然有局限性,但其及时、便捷和灵活的制度设计,扮演着十分重要的兜底性保护角色。针对我国现行《反不正当竞争法》对地理标志保护的立法疏漏和规则缺位,建议进一步修改《反不正当竞争法》第二章所列举的不正当竞争行为类型,增设地理标志不正当竞争条款,明确第17条中赔偿责任和第20条中诉讼主体的适用范围等,以加强对地理标志的反不正当竞争保护。 展开更多
关键词 反不正当竞争法 地理标志 兜底性保护 列举式条款
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