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《新疆植被及其利用》专著中未曾记载的植物群落类型 被引量:17
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作者 海鹰 张立运 李卫 《干旱区地理》 CSCD 北大核心 2003年第4期413-419,共7页
《新疆植被及其利用》( 1978)一书 ,限于当时的考察条件和成书较早 ,对下述植物群落类型未曾记载。它们分别是由园叶桦 (Betularotunaifolia) 、野巴旦 (Amygdalusledebouriana) 、银沙槐 (Ammodendronargnteum) 、准噶尔大戟 (Euphorbi... 《新疆植被及其利用》( 1978)一书 ,限于当时的考察条件和成书较早 ,对下述植物群落类型未曾记载。它们分别是由园叶桦 (Betularotunaifolia) 、野巴旦 (Amygdalusledebouriana) 、银沙槐 (Ammodendronargnteum) 、准噶尔大戟 (Euphorbiasoongarica) 、匍匐水柏枝 (Myricariaprostrata) 、塔克拉玛干柽柳 (Tamarixtaklamakanensis)、尖果沙枣 (Elaeagnusoxycarpa) 、沙棘 (Hippophaerhamnoides) 、新麦草 (Psathyrostachysjuncea) 、硬叶苔草(Carexmoocroftii) 展开更多
关键词 《新疆植被及其利用》 植物群落 类型 新疆
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“他者”的浮沉:评贾平凹长篇小说新作《高兴》 被引量:11
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作者 吴义勤 张丽军 《西安建筑科技大学学报(社会科学版)》 2008年第3期12-19,共8页
贾平凹新作《高兴》塑造了一个具有新质的农民形象——刘高兴。他自觉认同城市,却遭到城市中国的拒绝。"垃圾伴生物"是进城农民在"城市中国"存在的隐喻性描述,无论是表层话语还是深层文化结构,刘高兴都是"城... 贾平凹新作《高兴》塑造了一个具有新质的农民形象——刘高兴。他自觉认同城市,却遭到城市中国的拒绝。"垃圾伴生物"是进城农民在"城市中国"存在的隐喻性描述,无论是表层话语还是深层文化结构,刘高兴都是"城市中国"的他者。"最丑,也最俗"的五富是乡土中国农民形象的"代表"。刘高兴作为城市的"先适者",自觉地带领"五富们"进入城市生活之中。刘高兴追求的不是个体解放,而是一个群体的解放问题。拒绝个体超脱、追求群体解放的刘高兴形象使当代底层文学达到了一个新的思想高度,揭示贾平凹对当代乡土中国农民整体命运的思考。 展开更多
关键词 贾平凹 刘高兴 他者 乡土中国 底层文学
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社会排斥的结果:对象与影响因素 被引量:11
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作者 李森 张登浩 《心理研究》 2016年第3期10-16,共7页
社会排斥损害个体对归属需要的满足。研究发现,社会排斥不仅会对被排斥者带来影响,而且对排斥者和无关他人也会产生影响。而影响社会排斥结果的因素可以分为两个方面:个体因素和环境因素。未来的研究应该从排斥者、被排斥者和无关他人... 社会排斥损害个体对归属需要的满足。研究发现,社会排斥不仅会对被排斥者带来影响,而且对排斥者和无关他人也会产生影响。而影响社会排斥结果的因素可以分为两个方面:个体因素和环境因素。未来的研究应该从排斥者、被排斥者和无关他人等多个角度进行考虑,同时既考虑个体因素也要更加强调环境因素的作用,另外还要注意社会排斥的不同阶段、社会排斥产生的原因以及社会排斥的研究范式等在影响社会排斥结果中所发挥的作用。 展开更多
关键词 社会排斥 被排斥者 排斥者 排斥敏感性
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典型B超软故障的分析与排除 被引量:7
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作者 杨一挺 《影像技术》 CAS 2016年第1期63-64,共2页
B超是当代医疗学界应用较为广泛的一种设备,变成当前临床医学诊断应用较为频繁一种手段,其优势是对疾病判断准确性高,对病患损伤小等,对我们国家来讲,B超大量投入使用并没有很长时间,差不多三十年,对B超存在典型软故障方式方法进行判断... B超是当代医疗学界应用较为广泛的一种设备,变成当前临床医学诊断应用较为频繁一种手段,其优势是对疾病判断准确性高,对病患损伤小等,对我们国家来讲,B超大量投入使用并没有很长时间,差不多三十年,对B超存在典型软故障方式方法进行判断是具有深远研究意义与实践价值的。伴随使用年限与频率不断增长,B超稳定性会呈现下降态势,这时候那些叫医务工作者费神费心的软故障便会频频出现,会对正常医学检查构成非常大的阻碍。同一时间,相比较那些一眼就能看出的硬故障,软故障需要相关工作人员投入更多耐心与细心。所以,为综合提升B超软故障分析与排除效率,进一步提出相应解决方案,本文笔者在这方面做了大量研究,通过查找前人资料联系实际,并进行归纳总结,最终得出自己的一些心得体会,希望为我国医疗事业可持续发展尽些微薄之力。 展开更多
关键词 B超 软故障 分析 排除
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液压泵常见故障分析及排除方法 被引量:5
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作者 杨秀荣 《电子测试》 2013年第4X期149-150,共2页
液压泵是液压系统中动力元件,相当于人的"心脏",当液压泵出现故障后液压系统油液系统将无法正常工作。本文分别就三种液压泵对其常见的故障及排除方法进行了探讨。
关键词 液压泵 故障 分析 排除
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Macromolecular Crowding Enhances Thermal Stability of Rabbit Muscle Creatine Kinase 被引量:2
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作者 朱江 何华伟 李森 《Tsinghua Science and Technology》 SCIE EI CAS 2008年第4期454-459,共6页
The effect of dextran on the conformation (or secondary structure) and thermal stability of creatine kinase (CK) was studied using the far-ultraviolet (UV) circular dichroism (CD) spectra. The results showed t... The effect of dextran on the conformation (or secondary structure) and thermal stability of creatine kinase (CK) was studied using the far-ultraviolet (UV) circular dichroism (CD) spectra. The results showed that lower concentrations of dextran (less than 60 g/L) induced formation of the secondary CK structures. However, the secondary structure content of CK decreased when the dextran concentrations exceeded 60 g/L. Thermally induced transition curves were measured for CK in the presence of different concentrations of dextran by far-UV CD. The thermal transition curves were fitted to a two-state model by a nonlinear, least-squares method to obtain the transition temperature of the unfolding transition. An increase in the transition temperature was observed with the increase of the dextran concentration. These observations qualitatively accord with predictions of a previously proposed model for the effect of intermolecular excluded volume (macromolecular crowding) on protein stability and conformation. These findings imply that the effects of macromolecular crowding can have an important influence on our understanding of how protein folding occurs in vivo. 展开更多
关键词 thermal stability molecular crowding excluded volume effect DEXTRAN
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Properties of Measure-based Fuzzy Logic 被引量:1
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作者 LU Jian ping 1, ZHAO Shu xiang 2 (1. Department of Computer Science, Xi’an Institute of Posts and Telecommunications, Xi’an 710061, P.R. China 2. School of Computer Science, Xidian University, Xi’an 710071, P.R. China) 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2001年第4期29-33,共5页
Measure based fuzzy logic, which is constructed on the basis of eight axioms, is a seemingly powerful fuzzy logic. It possesses several remarkable properties. (1) It is an extended Boolean logic, satisfying all the p... Measure based fuzzy logic, which is constructed on the basis of eight axioms, is a seemingly powerful fuzzy logic. It possesses several remarkable properties. (1) It is an extended Boolean logic, satisfying all the properties of Boolean algebra, including the law of excluded middle and the law of contradiction. (2) It is conditional. Conditional membership functions play an important role in this logic. (3) The negation operator is not independently defined with the conjunction and disjunction operators, but on the contrary, it is derived from them. (4) Zadehs fuzzy logic is included in it as a particular case. (5) It gives more hints to the relationship between fuzzy logic and probability logic. 展开更多
关键词 fuzzy logic Boolean algebra measure based fuzzy logic extended Boolean algebra law of excluded middle law of contradiction
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Problem of living liver donation in the absence of deceased liver transplantation program:Mansoura experience 被引量:1
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作者 Mohamed Abdel Wahab Hosam Hamed +10 位作者 Tarek Salah Waleed Elsarraf Mohamed Elshobary Ahmed Mohamed Sultan Ahmed Shehta Omar Fathy Helmy Ezzat Amr Yassen Mohamed Elmorshedi Mohamed Elsaadany Usama Shiha 《World Journal of Gastroenterology》 SCIE CAS 2014年第37期13607-13614,共8页
We report our experience with potential donors for living donor liver transplantation(LDLT), which is the first report from an area where there is no legalized deceased donation program. This is a single center retros... We report our experience with potential donors for living donor liver transplantation(LDLT), which is the first report from an area where there is no legalized deceased donation program. This is a single center retrospective analysis of potential living donors(n = 1004) between May 2004 and December 2012. This report focuses on the analysis of causes, duration, cost, and various implications of donor exclusion(n = 792).Most of the transplant candidates(82.3%) had an experience with more than one excluded donor(median = 3). Some recipients travelled abroad for a deceased donor transplant(n = 12) and some died before finding a suitable donor(n = 14). The evaluation of an excluded donor is a time-consuming process(median = 3 d, range 1 d to 47 d). It is also a costly process with a median cost of approximately 70 USD(range 35 USD to 885 USD). From these results, living donor exclusion has negative implications on the patients and transplant program with ethical dilemmas and an economic impact. Many strategies are adopted by other centers to expand the donor pool; however, they are not all applicable in our locality. We conclude that an active legalized deceased donor transplantation program is necessary to overcome the shortage of available liver grafts in Egypt. 展开更多
关键词 Living donor Liver transplantation excluded donors Deceased donor Liver disease
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STIFFNESS AND EXCLUDED VOLUME EFFECTS ON CONFORMATION AND DYNAMICS OF POLYMERS:A SIMULATION STUDY 被引量:1
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作者 李安邦 Yuan-gen Yao Hong Xu 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2012年第3期350-358,共9页
This work investigates the effects of the excluded volume and especially those of the chain stiffness on the structural and dynamical properties of a model polymer chain. The theoretical framework is the same as in th... This work investigates the effects of the excluded volume and especially those of the chain stiffness on the structural and dynamical properties of a model polymer chain. The theoretical framework is the same as in the recent works by Steinhauser et al., where a Rouse approach is adopted. Our model differs in that our chains have a finite average bending angle. As in the works by Steinhauser et al., Langevin dynamic simulations were performed without hydrodynamic interactions. Whereas this doesn't impact the static properties we obtain, it also allows us to compare our results on dynamic properties to those predicted by Rouse theory, where hydrodynamic interactions are also neglected. Our results show that the structural properties are very sensitive to the chain stiffness, whereas the dynamic scaling laws remain the same as those by Rouse theory, with the prefactor depending on the persistence length. 展开更多
关键词 Scaling laws POLYMER STIFFNESS excluded volume effects.
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Fuzzy Set Operation Based on Measure Theory 被引量:1
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作者 Lu Jianping (Department of Computer, Xi’an Institute of Posts and Telecommunications,Xi’an 710061, P.R.China) Zhao Shuxiang (School of Computer, Xidian University, Xi’an 710071, P.R.China) 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 1997年第2期24-29,共6页
Differrent kinds of operations have been proposed in fuzzy set theory although Zadeh's operation is the most popoular. We discuss a new kind of fuzzy set operations which is based on measurement. In the measure b... Differrent kinds of operations have been proposed in fuzzy set theory although Zadeh's operation is the most popoular. We discuss a new kind of fuzzy set operations which is based on measurement. In the measure based operation, there are only two basic operators: operator for intersection and operator for union. These two operators are interrelated with each other, and conditional fuzzy measures(or conditional membership functions) are also included in these operators. Moreover, the operator for complement is not independently defined, and it is derived from the above two basic operators. The measure based operation brings to light some relations between Zadeh's operation and probabilistic operation. We show that both Zadeh's operation and probabilistic operation are special cases of measure based operators.We also discuss the problem of the law of excluded middle and the law of contradiction. It is shown that these laws still hold in fuzzy sets and this conclusion causes no difficulty in explaining the nature of fuzziness. 展开更多
关键词 fuzzy sets fuzzy set operations fuzzy measure law of excluded middle law of contradicton
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VISCOMETRIC INVESTIGATIONS OF POLYVINYLPYRROLIDONE IN MIXED SOLVENTS AND WITH VARYING TEMPERATURE 被引量:1
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作者 Omar Melad Omar Abu-Tiem Rajai Baraka 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2005年第4期367-371,共5页
The viscosity behavior of polyvinylpyrrolidone(PVP)has been determined at 25℃ in mixed solvents comprising water/dimethylformamide(DMF)and water/methanol(MeOH).Analysis of the data has considered the PVP as being bot... The viscosity behavior of polyvinylpyrrolidone(PVP)has been determined at 25℃ in mixed solvents comprising water/dimethylformamide(DMF)and water/methanol(MeOH).Analysis of the data has considered the PVP as being both host and guest polymer in solution.The intrinsic viscosity of PVP in DMF is higher than in water and in MeOH,but also increases in a mixed solvent with high water content because of the effect of polymer-solvent interactions.It was also found that the intrinsic viscosity of PVP at finite concentration,[η_(pvp)]_c decreases with an increase in the concentration of PVP in solution.The viscosity behavior of PVP in a mixed solvent is affected by the concentration-dependent intermolecular excluded volume effect,which can be quantitatively expressed by the parameter,b_Y,which reflects the shrinkage of PVP chain coils,resulting in a decrease of[η_(pvp)]_c.The effect of temperature on the viscosity behavior of PVP in MeOH shows that the interaction parameter increases up to a maximum value,and then decreases after a certain temperature. 展开更多
关键词 POLYVINYLPYRROLIDONE Intermolecular excluded volume effect Intrinsic viscosity
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COMPLEXITY ANALYSIS OF TIME SERIES GENERATED BY ELEMENTARY CELLULAR AUTOMATA 被引量:1
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作者 Qin Dakang Xie Huimin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第3期253-267,共15页
Using the tools of distinct excluded blocks, computational search and symbolic dynamics, the classification problem of all 256 elementary cellular automata is discussed from the point of view of time series generated ... Using the tools of distinct excluded blocks, computational search and symbolic dynamics, the classification problem of all 256 elementary cellular automata is discussed from the point of view of time series generated by them,and examples in each class are provided to explain the methods used. 展开更多
关键词 elementary cellular automaton time series distinct excluded block formal language Chomsky hierarchy
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汽轮机高压调门摆动的原因分析及处理 被引量:2
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作者 刘国栋 《科技创新与应用》 2017年第29期173-173,176,共2页
汽轮机高压调门是保证汽轮机调速及安全运行的重要设备,其调节品质的好坏直接影响汽轮机组转速和负荷的稳定控制,同时对机组的安全运行也起着至关重要的作用,文章针对东汽汽轮机在特定工况下存在的高压调门严重摆动问题的原因进行了深... 汽轮机高压调门是保证汽轮机调速及安全运行的重要设备,其调节品质的好坏直接影响汽轮机组转速和负荷的稳定控制,同时对机组的安全运行也起着至关重要的作用,文章针对东汽汽轮机在特定工况下存在的高压调门严重摆动问题的原因进行了深入分析,给出了较为完善的解决方案,对其他同类型电厂解决相似问题具有一定的借鉴作用。 展开更多
关键词 调门 摆动 分析 排除
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Letters to the Editor
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作者 Tomas S Bexelius Rickard Ljung 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2016年第4期443-445,共3页
The Editor welcomes submissions for possible publication in the Letters to the Editor section.Letters commenting on an article published in the Journal or other interesting pieces will be considered if they are receiv... The Editor welcomes submissions for possible publication in the Letters to the Editor section.Letters commenting on an article published in the Journal or other interesting pieces will be considered if they are received within 6 weeks of the time the article was published.Authors of the article being commented on will be given an opportunity to offer a timely response to the letter Authors of letters will be notified that the letter has been received. Unpublished letters cannot be returned. 展开更多
关键词 welcomes matching pieces obesity alcohol letter rendering adjustment ascertain excluded
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Excluded Minority of P8 for GF(4)-Representability
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作者 Seungho Ahn Boongbi Han 《Open Journal of Discrete Mathematics》 2016年第4期279-296,共18页
One of the mainly interesting things of matroid theory is the representability of a matroid. Finding the set of all excluded minors for the representability is the solution of the representability. In 2000, Geelen, Ge... One of the mainly interesting things of matroid theory is the representability of a matroid. Finding the set of all excluded minors for the representability is the solution of the representability. In 2000, Geelen, Gerards and Kapoor proved that  is the complete set of GF(4)-representability. In this paper, we show that is an excluded minor for GF(4)-representability. 展开更多
关键词 excluded Minor
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Theoretical model of biomacromolecule through nanopore including effects of electrolyte and excluded volume
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作者 Chibin ZHANG Xiaohui LIN Hao YANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第6期787-802,共16页
A theoretical model for the translocation process of biomacromolecule is developed based on the self-consistent field theory (SCFT), where the biomacromolecule is regarded as a self-avoiding polymer chain actuated b... A theoretical model for the translocation process of biomacromolecule is developed based on the self-consistent field theory (SCFT), where the biomacromolecule is regarded as a self-avoiding polymer chain actuated by the external potential. In this theoretical model, the external potential, the Coulomb electrostatic potential of the charged ions (the electrolyte effect), and the attractive interaction between the polymer and the nanopore (the excluded volume effect) are all considered, which have effects on the free energy landscape and conformation entropy during the translocation stage. The result shows that the entropy barrier of the polymer in the solution with high valence electrolyte is much larger than that with low valence electrolyte under the same condition, leading to that the translocation time of the DNA molecules in the solution increases when the valence electrolyte increases. In addition, the attractive interaction between the polymer and the nanopore increases the free energy of the polymer, which means that the probability of the translocation through the nanopore increases. The average translocation time decreases when the excluded volume effect parameter increases. The electrolyte effect can prolong the average translocation time. The simulation results agree well with the available experimental results. 展开更多
关键词 polymer through nanopore electrolyte effect excluded volume effect freeenergy conformation entropy
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Analysis of the efficacy and prognosis on first-line autologous hematopoietic stem cell transplantation of patients with multiple myeloma 被引量:1
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作者 邹徳慧 《China Medical Abstracts(Internal Medicine)》 2013年第2期115-116,共2页
Objective To explore the efficacy and prognosis of first-line autologous hematopoietic stem cell transplantation(ASCT) for newly diagnosed patients with multiple myeloma(MM).Methods From January 2005
关键词 MYELOMA HEMATOPOIETIC PROGNOSIS AUTOLOGOUS THALIDOMIDE excluded deletion maintenance prognostic progression
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CLINICAL OBSERVATION ON OSTEOPOROSIS TREATED WITH TRADITIONAL KIDNEY-TONIFYING MEDICAMENTS 被引量:1
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作者 梁立 江正玉 +1 位作者 刘中厚 刘维 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1994年第1期41-44,共4页
The method of scoring kidney deficiency symptoms and bone density was used to judge therapeutic efficacy on osteoporosis of traditional kidney-tonifying drugs. It was proved that the drugs not only improved clinical s... The method of scoring kidney deficiency symptoms and bone density was used to judge therapeutic efficacy on osteoporosis of traditional kidney-tonifying drugs. It was proved that the drugs not only improved clinical symptoms but also delayed the developmental pro-cess of this disorder. It also verified the correctness of the traditional theory that the kidney dominates the bone and generates the marrow. 展开更多
关键词 OSTEOPOROSIS RADIX verified developmental JUDGE ESSENCE CORRECTNESS prescription excluded quantitatively
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汽车发动机异响故障分析与诊断 被引量:1
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作者 孙志刚 《湖南农机(学术版)》 2011年第2期99-100,共2页
分析了汽车发动机异响故障诊断方法、汽车发动机异常响声辨别方法、发动机异响部位诊断方法。汽车发动机维修人员在维修的过程中,掌握了这些基本知识,并在实践中不断总结、积累经验,就一定能够对发动机常见异响作出及时、正确的诊断,从... 分析了汽车发动机异响故障诊断方法、汽车发动机异常响声辨别方法、发动机异响部位诊断方法。汽车发动机维修人员在维修的过程中,掌握了这些基本知识,并在实践中不断总结、积累经验,就一定能够对发动机常见异响作出及时、正确的诊断,从而保证发动机与汽车良好的技术状况。 展开更多
关键词 发动机 异响 诊断方法 排除
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CATALAN NUMBERS, DYCK LANGUAGE AND TIME SERIES OF ELEMENTARY CELLULAR AUTOMATON OF RULE 56 被引量:1
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作者 QINDakang XIEHuimin 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2005年第3期404-418,共15页
A new approach to study the evolution complexity of cellular automata is proposed and explained thoroughly by an example of elementary cellular automaton of rule 56. Using the tools of distinct excluded blocks, comput... A new approach to study the evolution complexity of cellular automata is proposed and explained thoroughly by an example of elementary cellular automaton of rule 56. Using the tools of distinct excluded blocks, computational search and symbolic dynamics, the mathematical structure underlying the time series generated from the elementary cellular automaton of rule 56 is analyzed and its complexity is determined, in which the Dyck language and Catalan numbers emerge naturally. 展开更多
关键词 elementary cellular automaton time series distinct excluded block dycklanguage catalan numbers
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