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Regular Quasi Cyclic Low Density Parity Check Codes with Girth 8 from Elementary Number Theory 被引量:1
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作者 He Guofeng Li Xiangxue +2 位作者 Li Qiang Zhou Zhiheng Zheng Dong 《China Communications》 SCIE CSCD 2012年第4期80-88,共9页
This paper is concerned with (3,n) and (4,n) regular quasi-cyclic Low Density Parity Check (LDPC) code constructions from elementary number theory.Given the column weight,we determine the shift values of the circulant... This paper is concerned with (3,n) and (4,n) regular quasi-cyclic Low Density Parity Check (LDPC) code constructions from elementary number theory.Given the column weight,we determine the shift values of the circulant permutation matrices via arithmetic analysis.The proposed constructions of quasi-cyclic LDPC codes achieve the following main advantages simultaneously:1) our methods are constructive in the sense that we avoid any searching process;2) our methods ensure no four or six cycles in the bipartite graphs corresponding to the LDPC codes;3) our methods are direct constructions of quasi-cyclic LDPC codes which do not use any other quasi-cyclic LDPC codes of small length like component codes or any other algorithms/cyclic codes like building block;4)the computations of the parameters involved are based on elementary number theory,thus very simple and fast.Simulation results show that the constructed regular codes of high rates perform almost 1.25 dB above Shannon limit and have no error floor down to the bit-error rate of 10-6. 展开更多
关键词 quasi-cyclic LDPC code error floor Shannon limit number theory
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基于追溯码和药品批号融合的智慧药房全流程管理体系构建
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作者 张子阳 邵丹妍 +2 位作者 凡俊娟 包健安 马晶晶 《中国药房》 北大核心 2026年第5期565-570,共6页
目的构建基于药品批号和追溯码融合的智慧药房全流程管理体系,解决中心药房拆零药品追溯码上传率低与追溯难的问题,提升中心药房精细化管理水平与用药安全。方法遵循FOCUS-PDCA框架(发现问题、组织团队、澄清现状、理解原因、选择方案-... 目的构建基于药品批号和追溯码融合的智慧药房全流程管理体系,解决中心药房拆零药品追溯码上传率低与追溯难的问题,提升中心药房精细化管理水平与用药安全。方法遵循FOCUS-PDCA框架(发现问题、组织团队、澄清现状、理解原因、选择方案-计划、执行、检查、处理),实施优化批号管理流程、引入“预扫描登记”技术及建立动态“码池”机制等举措,构建药品批号追溯码管理体系;并基于2025年6-8月的我院医保上传数据与业务运行指标,对比分析体系实施前后的管理效能差异。结果我院成功构建了药品批号追溯码管理体系,实现了住院药品特别是拆零药品的“一物一码”全流程与批号关联。应用该体系后,住院药品追溯码上传率为100%,显著高于我市其他三级医院住院药品平均上传率(最高仅为23.22%,P<0.001);库存盘点误差率由0.9%降至0.3%(降幅为66.7%);日均调剂内部差错数量由1.43起下降至0.37起;临时医嘱平均调配时间(14.75 min)恢复至该体系实施前的常规水平(14.42 min)。结论该体系通过“预扫描登记-码池管理-闭环追溯”模式,实现了单个最小包装单位药品的可追溯,提高了追溯码上传率,在大幅降低发药差错率的同时,并不增加临时医嘱调配的时间成本,兼顾了效率与追溯闭环。 展开更多
关键词 药品追溯码 批号 码池 中心药房 拆零药品 闭环管理 智慧药房
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Digital Number的数学表达问题
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作者 张行清 庞芳 +2 位作者 姚振东 李昭春 张行明 《中国科技术语》 2020年第6期77-85,共9页
Digital Number(DN)是信息科学关于信息采集的术语,需要界定和理顺DN各方面的关系,解决DN在遥感技术、数学、计算机科学的表达问题。阐述DN基本认识及其应有常态,给出DN名称和DN含义,梳理DN来源及其演变,明确DN与模拟量关系、DN与数值... Digital Number(DN)是信息科学关于信息采集的术语,需要界定和理顺DN各方面的关系,解决DN在遥感技术、数学、计算机科学的表达问题。阐述DN基本认识及其应有常态,给出DN名称和DN含义,梳理DN来源及其演变,明确DN与模拟量关系、DN与数值关系及DN与非DN界限,陈述数字结构、数字标识及不同系统层面DN,形成10方面正面共识,供分析对照。对DN表达问题归纳为DN代表关系、技术关系、数学关系、数值关系、标识关系5种类型,分析这些相应关系的表达缺陷,对DN有关方面做表达示范。创新成果:界定DN与模拟量关系;归纳DN的感性错误与其错误导向关系;重新解释数值及数值类型,对数值做定义,数值类型应包括DN分支,数值应包括DN来源成员;完善DN、数值及非数值式中参数的相应描述;规范数字术语在数字技术及数学的使用。达到提高DN及其关联的认识,促进数学的发展,利于消除遥感技术、数学、计算机科学出现的DN各种表达问题。 展开更多
关键词 数字编码 DN 表达 模拟量 数值 数值类型
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Beyond a Quartic Polynomial Modeling of the DNA Double-Helix Genetic Code 被引量:3
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作者 Hans Hermann Otto 《Journal of Applied Mathematics and Physics》 2021年第10期2558-2577,共20页
By combination of finite number theory and quantum information, the complete quantum information in the <em>DNA</em> genetic code has been made likely by <em>Planat et al</em>. (2020). In the p... By combination of finite number theory and quantum information, the complete quantum information in the <em>DNA</em> genetic code has been made likely by <em>Planat et al</em>. (2020). In the present contribution a varied quartic polynomial contrasting the polynomial used by <em>Planat et al</em>. is proposed that considered apart from the golden mean also the fifth power of this dominant number of nature to adapt the code information. The suggested polynomial is denoted as <em>g</em>(<em>x</em>) = <em>x</em><sup>4</sup> - <em>x</em><sup>3</sup> - (4 - <em><i style="white-space:normal;">&#981;</i></em><sup>2</sup> )<em>x</em><sup>2</sup> + (4 – <i>&#981;</i><sup>2</sup>)x + 1, where <img src="Edit_40efe764-d690-499f-8424-129f9ca46f78.bmp" alt="" /> is the golden mean. Its roots are changed to more golden mean based ones in comparison to the <em>Planat</em> polynomial. The new coefficients 4 – <em>&#981;</em><sup>2</sup> instead of 4 would implement the fifth power of the golden mean indirectly applying <img src="Edit_5b44b644-3f59-4fad-a586-ec5345ba6be4.bmp" alt="" />. As an outlook, it should be emphesized that the connection between genetic code and resonance code of the <em>DNA</em> may lead us to a full understanding of how nature stores and processes compacted information and what indeed is consciousness linking everything with each other suggestedly mediated by all-pervasive dark constituents of matter respectively energy. The number-theoretical approach to <em>DNA</em> coding leads to the question about the helical structure of the electron. 展开更多
关键词 DNA Genetic code DNA Resonance code Qartic Polymial Golden Mean Silver Mean Fifth Power of the Golden Mean Fiboacci number 13 α-Helix Icosahedron Equation number Theory Quantum Computation Consciousness Dark Energy Electron’s Structure
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Integrated management system of agro-fishery products based on QR-code 被引量:1
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作者 Namjin Bae Yongyun Cho +1 位作者 Jongsun Choi Jaeyoung Choi 《Journal of Measurement Science and Instrumentation》 CAS 2013年第3期252-255,共4页
Recently,both the importance and awareness relating to food safety relating to agrochemicals,chemical fertilizers,the pollution of ecosystem and unwholesome foods are growing rapidly.For the same reason,the purchaser&... Recently,both the importance and awareness relating to food safety relating to agrochemicals,chemical fertilizers,the pollution of ecosystem and unwholesome foods are growing rapidly.For the same reason,the purchaser's curiosity increases to know about the production process which can be accomplished by production traceability system.The traceability system can store and superintend the specific attribute information about products regarding the productive centre,producer and production finish data.The products undergo various circulation processes and they are being managed by individually constructed traceability system.Thus,it is difficult for the producer and the consumer to guarantee the safety from transpirable issues about the falsification of production traceability because the traceability information can be re-produced by forging through various ways.So in this paper,we proposed a system for integrated management of agro-fishery products based on quick response code(QR-code)for forgery prevention which may help to solve these issues.The proposed system makes QR-code using production information provided by producer.And then it is provided to the distributor and the consumer through integrated service model using the QR-code.Therefore,this system make sure to provide the same production traceability about the products to the distributor and the consumer and always keeps both updated with the same information. 展开更多
关键词 quick response code (QR-code production traceability traceability systemCLC number:TP391.44 Document code:AArticle ID:1674-8042(2013)03-0252-04
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On Locating Numbers of Graphs
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作者 Baogen Xu Chunhua Li Zhizhu Fan 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2018年第1期93-96,共4页
Let G =( V,E) be a connected graph and W = { w_1,w_2,…,w_k} be an ordered subset of V( G).For any vertex v ∈V,the locating code of v with respect to W is the k-vector CW( v) = { d( v,w_1),d( v,w_2),…,d( v,w_k) },W ... Let G =( V,E) be a connected graph and W = { w_1,w_2,…,w_k} be an ordered subset of V( G).For any vertex v ∈V,the locating code of v with respect to W is the k-vector CW( v) = { d( v,w_1),d( v,w_2),…,d( v,w_k) },W is said to be a locating set of G if distinct vertices have the distinct locating code,and the locating number of G is defined as: Loc( G) = min{ | W| : W is a locating set of G}.We study the locating set and locating number of a graph G,obtain some bounds for the locating numbers of graphs,and determine the exact value of Loc( G) for some special classes of graphs,such as cycles,wheels,complete t-partite graph and some Cartesian products of paths and cycles. In addition,we also prove that Loc( T) ≥Δ-1 holds for all trees T with maximum degree Δ,and shows a tree T with Loc( T) = Δ-1. 展开更多
关键词 GRAPH locating code locating SET locating number CARTESIAN products
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The Positions and Number of Flux Loops and Magnetic Probes for the HT-7U Superconducting Tokamak
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作者 沈飙 罗家融 +1 位作者 万宝年 王华中 《Plasma Science and Technology》 SCIE EI CAS CSCD 2003年第3期1785-1794,共10页
The plasma shape and other paremeters such as /3P, li is important for the tokamak deveice where the plasma has a non-circular cross-section of sufficient elongation. The measuered signals of magnetic probes and flux ... The plasma shape and other paremeters such as /3P, li is important for the tokamak deveice where the plasma has a non-circular cross-section of sufficient elongation. The measuered signals of magnetic probes and flux loops are used to reconstruct the plasma shape and the current profile in device operation and plasma shape feed back control system. So the number and positions of magnetic probes and flux loops provides the basis of the plasma reconstruction. This paper instroduce how to use EFIT code (equilibrium fitting code) to determine the number and positions of the magnetic probes and flux loops. The simulation result is given also. 展开更多
关键词 equilibrium reconstruction EFIT code positions and number magnetic probes and flux loops
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Number in Mathematical Cryptography
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作者 Nathan Hamlin 《Open Journal of Discrete Mathematics》 2017年第1期13-31,共19页
With the challenge of quantum computing ahead, an analysis of number and representation adequate to the task is needed. Some clarifications on the combinatorial nature of representation are presented here;this is rela... With the challenge of quantum computing ahead, an analysis of number and representation adequate to the task is needed. Some clarifications on the combinatorial nature of representation are presented here;this is related to the foundations of digital representations of integers, and is thus also of interest in clarifying what numbers are and how they are used in pure and applied mathematics. The author hopes this work will help mathematicians and computer scientists better understand the nature of the Generalized Knapsack Code, a lattice-based code which the author believes to be particularly promising, and the use of number in computing in general. 展开更多
关键词 number Theory Quantum COMPUTING Public-Key CRYPTOGRAPHY Generalized KNAPSACK code Combinatorial code
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A General Conclusion on Lucas Numbers of the Form px^(2),Where p Is Prime
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作者 Zhou Chizhong(BasicCourses Department) 《岳阳大学学报》 CAS 1995年第2期10-16,共7页
ABSTRACT. Led。 be the n^(th) Lucas number, n>0. Let p be an odd prime. In this paperwe prove a general theorem. According to the theorem we give an algorithm by using whichthe equationl-(n)=px^(2) can be ... ABSTRACT. Led。 be the n^(th) Lucas number, n>0. Let p be an odd prime. In this paperwe prove a general theorem. According to the theorem we give an algorithm by using whichthe equationl-(n)=px^(2) can be solved for arbitrary given p.Por example,we find its all solutionsfor 1000<p<40000. By the end of the paper an Interestingconjecture Is presented. 展开更多
关键词 AND PHRASES Lucas number 1991 AMS SUBJECT CLASSIFICATION code 11B39
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The “3 Genomic Numbers” Discovery: How Our Genome Single-Stranded DNA Sequence Is “Self-Designed” as a Numerical Whole
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作者 Jean-Claude Perez 《Applied Mathematics》 2013年第10期37-53,共17页
This article proves the existence of a hyper-precise global numerical meta-architecture unifying, structuring, binding and controlling the billion triplet codons constituting the sequence of single-stranded DNA of the... This article proves the existence of a hyper-precise global numerical meta-architecture unifying, structuring, binding and controlling the billion triplet codons constituting the sequence of single-stranded DNA of the entire human genome. Beyond the evolution and erratic mutations like transposons within the genome, it’s as if the memory of a fossil genome with multiple symmetries persists. This recalls the “intermingling” of information characterizing the fractal universe of chaos theory. The result leads to a balanced and perfect tuning between the masses of the two strands of the huge DNA molecule that constitute our genome. We show here how codon populations forming the single-stranded DNA sequences can constitute a critical approach to the understanding of junk DNA function. Then, we suggest revisiting certain methods published in our 2009 book “Codex Biogenesis”. In fact, we demonstrate here how the universal genetic code table is a powerful analytical filter to characterize single-stranded DNA sequences constituting chromosomes and genomes. We can then show that any genomic DNA sequence is featured by three numbers, which characterize it and its 64 codon populations with correlations greater than 99%. The number “1” is common to all sequences, expressing the second law of Chargaff. The other 2 numbers are related to each specific DNA sequence case characterizing life species. For example, the entire human genome is characterized by three remarkable numbers 1, 2, and Phi = 1.618 the golden ratio. Associated with each of these three numbers, we can match three axes of symmetry, then “imagine” a kind of hyperspace formed by these codon populations. Then we revisit the value (3-Phi)/2 which is probably universal and common to both the scale of quarks and atomic levels, balancing and tuning the whole human genome codon population. Finally, we demonstrate a new kind of duality between “form and substance” overlapping the whole human genome: we will show that—simultaneously with the duality between genes and junk DNA—there is a second layer of embedded hidden structure overlapping all the DNA of the whole human genome, dividing it into a second type of duality information/redundancy involving golden ratio proportions. 展开更多
关键词 Genetic code CODON Populations Junk DNA Cancer Genomics Chromosomal Translocations Genomes Diversity Chromosomes Diversity WHOLE Human GENOME DNA SEQUENCE “Phi” the Golden Ratio Fibonacci numberS Information Theory SYMMETRY Cellular Automata Chargaff’s CODON Level SYMMETRY Principle Fractal Self-Similarity “e” Euler’s number “Pi” form and Substance Redundancy Encryption
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A novel OCDMA drop unit based on fiber gratings and 2D wavelength-time codes
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作者 CHEN Biao WANG Fu-chang +1 位作者 HU Jian-dong HE Sai-ling 《Optoelectronics Letters》 EI 2005年第1期53-56,共4页
A novel drop unit for the optical code-division multiple access(OCDMA) based on fiber Bragg gratings and two-dimensional wavelength-time code is studied.The simple OCDMA drop unit can drop a code channel without distu... A novel drop unit for the optical code-division multiple access(OCDMA) based on fiber Bragg gratings and two-dimensional wavelength-time code is studied.The simple OCDMA drop unit can drop a code channel without disturbing the rest code channels.A similar unit for dropping a group of code channels is also proposed.Numerical simulation is given.The system delay can decrease by substituting the electrieal driving optical switch with a specific optical driving.The single channel drop unit can also be the basis for multiple channels drop. 展开更多
关键词 CLC number TN913.7 Document code
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Low-Complexity Optimization Algorithm for Irregular Low-Density Parity-Check Codes
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作者 左健存 邵宇丰 桂林 《Journal of Donghua University(English Edition)》 EI CAS 2013年第4期330-335,共6页
A low-complexity algorithm is proposed in this paper in order to optimize irregular low-density parity-check (LDPC) codes.The algorithm proposed can calculate the noise threshold by means of a one-dimensional densit... A low-complexity algorithm is proposed in this paper in order to optimize irregular low-density parity-check (LDPC) codes.The algorithm proposed can calculate the noise threshold by means of a one-dimensional density evolution and search the optimal degree profiles with fast-convergence differential evolution,so that it has a lower complexity and a faster convergence speed.Simulation resuits show that the irregular LDPC codes optimized by the presented algorithm can also perform better than Turbo codes at moderate block length even with less computation cost. 展开更多
关键词 irregular low-density parity-check (LDPC) codes Turbo codes optimizationCLC number:TN911.22Document code:AArticle ID:1672-5220(2013)04-0330-06
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Efficient Early Termination Strategy for LDPC Codes in GPS Systems
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作者 Feng Wang Jin-Hai Li +1 位作者 Jin-Hai Sun Yue-Peng Yan 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第6期118-122,共5页
By exploiting the structural features of L1C messages,a novel Early Termination( ET) strategy is proposed to speed up the decoding of low-density parity-check( LDPC) codes in the GPS system. The proposed strategy is b... By exploiting the structural features of L1C messages,a novel Early Termination( ET) strategy is proposed to speed up the decoding of low-density parity-check( LDPC) codes in the GPS system. The proposed strategy is based on the cyclic redundancy check( CRC) of the messages in the subframes 2 and 3. The simulation results show that average number of iterations of the proposed strategy is less than that of the standard ET strategy,with nearly no degradation in decoding performance. Besides,the proposed ET strategy can be efficiently implemented in a sequential or parallel manner. Thus,the proposed ET strategy is attractive for practical purposes. 展开更多
关键词 GPS system low-density parity-check (LDPC) codes early termination (ET) strategy cyclic redundancy check (CRC)CLC number:TN911.22 Document code:AArticle ID:1005-9113(2013)06-0118-05
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企业物品二维码编码及应用标准化研究 被引量:1
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作者 邓辉 王毅 张辉 《中国标准化》 2025年第3期35-39,共5页
本文基于标准研究了二维码码制、数据结构和标识方式,提出企业结合二维码应用场景选择编码型数据结构或网址型数据结构,采用一种或几种二维码码制,规范二维码编码、译码、标记、印制要求,利用二维码技术实现物品信息的自动识别与采集。
关键词 物品 二维码 编码 代码 标识 标准化
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物品编码与编目术语的辨析 被引量:1
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作者 张辉 王毅 邓辉 《中国标准化》 2025年第3期21-25,共5页
本文研究了现代编目、编码概念的形成和释义,分析了物品基础数据建设中编目、编码的内涵,结合编目编码术语普及应用情况,提出物品标识和基础数据建设应使用“物品编码(Article Numbering)”术语,物资谱系建设可使用“物资编目(material ... 本文研究了现代编目、编码概念的形成和释义,分析了物品基础数据建设中编目、编码的内涵,结合编目编码术语普及应用情况,提出物品标识和基础数据建设应使用“物品编码(Article Numbering)”术语,物资谱系建设可使用“物资编目(material cataloging)”术语,大力推广与国际接轨的物品编码术语,准确翻译术语,避免理解偏差。 展开更多
关键词 物品 编码 代码 编目 术语
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企业物品编码发展趋势研究
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作者 张辉 王毅 邓辉 《中国标准化》 2025年第3期26-29,91,共5页
本文研究了企业物品编码方法、编码技术的发展趋势,提出企业结合物品编码应用场景,从顶层规划,采用应用范围广的编码标准,推动编码业务专业化。中小企业应充分利用已有物品编码资源,甚至可以把编码业务外包给专业编码机构;大型企业可以... 本文研究了企业物品编码方法、编码技术的发展趋势,提出企业结合物品编码应用场景,从顶层规划,采用应用范围广的编码标准,推动编码业务专业化。中小企业应充分利用已有物品编码资源,甚至可以把编码业务外包给专业编码机构;大型企业可以按“新基建”模式积极开展物品编码基础数据建设,服务企业数字化转型。 展开更多
关键词 物品 编码 代码 编目
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圆截面高柔结构风效应现场实测与规范参数讨论
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作者 丁伟亮 王子夏 +2 位作者 王磊 陈守祥 黄楠 《建筑结构》 北大核心 2025年第20期148-156,共9页
圆截面高柔结构因横风向振动而发生倒塌或破坏的案例屡见不鲜,原因之一为规范设计结果与实测结果差异较大。针对这一问题,对一座210m高烟囱进行了风效应现场实测,统计分析了现场实测数据和现有研究中的大量相关实测结果,对比分析了不同... 圆截面高柔结构因横风向振动而发生倒塌或破坏的案例屡见不鲜,原因之一为规范设计结果与实测结果差异较大。针对这一问题,对一座210m高烟囱进行了风效应现场实测,统计分析了现场实测数据和现有研究中的大量相关实测结果,对比分析了不同国家规范在计算横风向荷载时对关键参数的取值差异。结果表明,实测结果和规范参数取值均有较大差异。在此基础上,对中国规范横风向荷载计算方法中升力系数、斯托罗哈数、结构阻尼比的取值进行讨论,给出了初步修正方法,并结合8座实际结构项目,检验了初步修正方法的适用性。 展开更多
关键词 圆截面高柔结构 风荷载规范 现场实测 升力系数 斯托罗哈数 结构阻尼比
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融合反向学习的精英选择遗传算法
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作者 闵云霄 潘峰 《长江信息通信》 2025年第3期78-80,共3页
针对传统遗传算法(SGA)在求解问题时后期局部搜索寻优能力不足,导致全局搜索范围受限,易陷入早熟现象与收敛速度较慢的问题。基于融合反向学习(OBL)思想、精英选择策略以及螺旋式搜索理念,提出一种改进的实数编码遗传算法EOBLGA。首先... 针对传统遗传算法(SGA)在求解问题时后期局部搜索寻优能力不足,导致全局搜索范围受限,易陷入早熟现象与收敛速度较慢的问题。基于融合反向学习(OBL)思想、精英选择策略以及螺旋式搜索理念,提出一种改进的实数编码遗传算法EOBLGA。首先在生成初始种群环节采用反向学习方式,以提升最优解的精度与收敛速度;然后采取种群划分挑选精英父代的思想进行螺旋式交叉操作,增强算法的全局搜索能力;最后采用正余弦混合突变操作,避免算法陷入局部最优的同时加快算法收敛。在测试函数的仿真实验结果表明,该算法不易陷入早熟收敛,并在收敛性能与求解精度上相较于原始SGA更优,验证了算法的有效性。 展开更多
关键词 遗传算法 实数编码 精英种群 反向学习 螺旋搜索
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柠檬草叶绿体基因组密码子偏好性分析
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作者 牟贞才 吴佳奇 +1 位作者 李浚朋 肖强 《湖北民族大学学报(自然科学版)》 2025年第3期327-333,共7页
为解析柠檬草[Cymbopogon citratus(DC.)Stapf]叶绿体基因组密码子使用偏好及其进化驱动因素,通过系统分析其密码子模式,为后续基因组功能研究与种质资源开发提供依据。基于美国国家生物技术信息中心(national center for biotechnology... 为解析柠檬草[Cymbopogon citratus(DC.)Stapf]叶绿体基因组密码子使用偏好及其进化驱动因素,通过系统分析其密码子模式,为后续基因组功能研究与种质资源开发提供依据。基于美国国家生物技术信息中心(national center for biotechnology information,NCBI)数据库获取柠檬草叶绿体基因组完整序列,筛选50条蛋白质编码序列(protein-coding sequences,CDS)。结合有效密码子数量绘图(effective number of codons plot,ENC-plot)、奇偶规则2绘图(parity rule 2 plot,PR2-plot)和中性绘图等方法,探究密码子使用偏好性及影响因素。柠檬草叶绿体基因组整体鸟嘌呤和胞嘧啶(guanine and cytosine,GC)含量为38.70%,第3位GC含量(GC_(3))均值为29.60%,均低于其他同科物种。密码子适应指数(codon adaptation index,CAI)均值为0.17,有效密码子数量(effective number of codons,ENC)均值为48.62,表明密码子偏好性较弱。筛选出30个高频使用密码子,其中26个为高表达密码子;进一步确定12个兼具高频率与高表达密度的最优密码子,如亮氨酸和丙氨酸等。该研究表明,自然选择是柠檬草叶绿体基因组密码子偏好性形成的主要驱动力。 展开更多
关键词 柠檬草 叶绿体基因组 密码子使用偏好 蛋白质编码序列 密码子适应指数 有效密码子数量 自然选择
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腹腔镜和开放手术行精索静脉曲张腹膜后高位结扎术的对比 被引量:48
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作者 蒋志强 曾青 +2 位作者 钟狂飚 何乐业 蒋先镇 《中国内镜杂志》 CSCD 2004年第6期31-32,35,共3页
目的对比评价腹腔镜精索静脉高位结扎术和开放手术经腹膜后精索静脉高位结扎术治疗精索静脉曲张的临床应用价值。方法回顾性分析34例应用腹腔镜精索静脉高位结扎术和42例应用开放手术经腹膜后精索静脉高位结扎术的病例。结果两组在手术... 目的对比评价腹腔镜精索静脉高位结扎术和开放手术经腹膜后精索静脉高位结扎术治疗精索静脉曲张的临床应用价值。方法回顾性分析34例应用腹腔镜精索静脉高位结扎术和42例应用开放手术经腹膜后精索静脉高位结扎术的病例。结果两组在手术时间和术后住院时间上均无明显差异。术后恢复快,随访无复发和睾丸萎缩。结论对于一侧精索静脉曲张,腹腔镜精索静脉高位结扎和小切口腹膜后精索静脉高位结扎并无明显的优劣之分。双侧和复发的精索静脉曲张,可以优先考虑腹腔镜手术。 展开更多
关键词 精索静脉曲张 腹腔镜 开放手术
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