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SOME EXAMPLES OF TRANSITION SPANS MINERALIZING AND ANALYSIS OFTHEIR DYNAMICS
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作者 BI Hua1, ZHAO Zhi zhong1, ZHU Wei huang2, YANG Yuan gen2,HUANG Lan3 and LIU Qiang3(1. Department of Resources, Environment and Tourism, Hainan Normal College, Haikou 571158, China 2. Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China 3. Biology Department, Hainan Normal College,Haikou 571158,China) 《Geotectonica et Metallogenia》 2002年第1期89-92,共4页
The transitional span is a special environment for deposits. Taking peat, oil gas, metallic deposits as examples, this paper discusses the spatial temporal transitional characteristics of mineralization in transitiona... The transitional span is a special environment for deposits. Taking peat, oil gas, metallic deposits as examples, this paper discusses the spatial temporal transitional characteristics of mineralization in transitional regions, points out the importance of the mineralization in transition spans, and analyses their dynamics finally. 展开更多
关键词 TRANSITION spans ORE formation examples DYNAMICS
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L(s,t) edge spans of trees and product of two paths 被引量:2
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作者 牛庆杰 林文松 宋增民 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期639-642,共4页
L( s, t)-labeling is a variation of graph coloring which is motivated by a special kind of the channel assignment problem. Let s and t be any two nonnegative integers. An L (s, t)-labeling of a graph G is an assig... L( s, t)-labeling is a variation of graph coloring which is motivated by a special kind of the channel assignment problem. Let s and t be any two nonnegative integers. An L (s, t)-labeling of a graph G is an assignment of integers to the vertices of G such that adjacent vertices receive integers which differ by at least s, and vertices that are at distance of two receive integers which differ by at least t. Given an L(s, t) -labeling f of a graph G, the L(s, t) edge span of f, βst ( G, f) = max { |f(u) -f(v)|: ( u, v) ∈ E(G) } is defined. The L( s, t) edge span of G, βst(G), is minβst(G,f), where the minimum runs over all L(s, t)-labelings f of G. Let T be any tree with a maximum degree of △≥2. It is proved that if 2s≥t≥0, then βst(T) =( [△/2 ] - 1)t +s; if 0≤2s 〈 t and △ is even, then βst(T) = [ (△ - 1) t/2 ] ; and if 0 ≤2s 〈 t and △ is odd, then βst(T) = (△ - 1) t/2 + s. Thus, the L(s, t) edge spans of the Cartesian product of two paths and of the square lattice are completely determined. 展开更多
关键词 L(s t) -labeling L(s t) edge span TREE Cartesian product square lattice
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Real edge spans of distance two labelings of graphs 被引量:1
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作者 戴本球 林文松 《Journal of Southeast University(English Edition)》 EI CAS 2009年第4期557-562,共6页
An L(j, k)-labeling of a graph G is an assignment of nonnegative integers to the vertices of G such that adjacent vertices receive integers which are at least j apart, and vertices at distance two receive integers w... An L(j, k)-labeling of a graph G is an assignment of nonnegative integers to the vertices of G such that adjacent vertices receive integers which are at least j apart, and vertices at distance two receive integers which are at least k apart. Given an L(j, k)-labeling f of G, define the L(j, k) edge span of f, βj,k(G,f) =max{ |f(x)-f(y)|: {x,y}∈E(G)}. The L(j,k) edge span of G, βj,k (G) is min βj,k( G, f), where the minimum runs over all L(j, k)-labelings f of G. The real L(.j, k)-labeling of a graph G is a generalization of the L(j, k)-labeling. It is an assignment of nonnegative real numbers to the vertices of G satisfying the same distance one and distance two conditions. The real L(j, k) edge span of a graph G is defined accordingly, and is denoted by βj,k(G). This paper investigates some properties of the L(j, k) edge span and the real L(j, k) edge span of graphs, and completely determines the edge spans of cycles and complete t-partite graphs. 展开更多
关键词 L( j k -labeling real L(j k -labeling L(j k) edge span real L(j k) edge span frequency assignment
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TIBET ARCHIVES:Rich Collection Spans Some 700 Years
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作者 MA LIHUA 《China's Tibet》 1996年第1期10-11,共2页
TIBETARCHIVES:RichCollectionSpansSome700Years¥//MALIHUALhasaplayedhostthispastAugusttoanInternationalSymposi... TIBETARCHIVES:RichCollectionSpansSome700Years¥//MALIHUALhasaplayedhostthispastAugusttoanInternationalSymposiumonTibet'sArchiv... 展开更多
关键词 TIBET ARCHIVES:Rich Collection spans Some 700 Years
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Safe mining practices under wide spans in underground non-caving mines——Case studies 被引量:2
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作者 J.J.Ran 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第4期535-540,共6页
Mining under wide span is of concern as it increases the probability of back caving causing personnel injury and equipment damage in underground mines in open stoping and underhand drift-and-fill methods.Though restri... Mining under wide span is of concern as it increases the probability of back caving causing personnel injury and equipment damage in underground mines in open stoping and underhand drift-and-fill methods.Though restricting personnel access to well supported lateral development is commonly practiced,it is not always possible to implement this requirement due to various factors such as ore loss control,drilling equipment limitations,availability of remote operating capacity and consideration of productivity.Even with rules implemented to limit personnel entry into openings with wide spans,the hazards of equipment damage and back caving still exist.Over the years,different practices have been reported and adopted to minimize risks associated with exposure to large spans in various underground mines.Lessons from these practices are beneficial to current and future mines with challenges of safe extraction of thick deposits in a non-caving setting.This paper briefly summarizes practices in mining wide orebodies using the open stoping method without personnel access and underhand mining using the drift-andfill method with personnel exposure in the industry and presents cases from Kinross mines where the hanging pillar design was tested,and stope backs were naturally and artificially supported for extraction under wide spans using the open stoping method. 展开更多
关键词 Mine safety WIDE SPAN Back stability Underhand mining HANGING PILLAR
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Entity and Relationship Extraction with High-quality Spans and Enhanced Marker Strategies
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作者 Qibin Li Nianmin Yao Nai Zhou 《Machine Intelligence Research》 2025年第2期289-303,共15页
Entity and relation extraction is a critical task in information extraction.Recent approaches have emphasized obtaining improved span representations.However,existing work suffers from two major drawbacks.First,there ... Entity and relation extraction is a critical task in information extraction.Recent approaches have emphasized obtaining improved span representations.However,existing work suffers from two major drawbacks.First,there is an overabundance of low-quality candidate spans,which hinders the effective extraction of information from high-quality candidate spans.Second,the information encoded by existing marker strategies is often too simple to fully capture the nuances of the span,resulting in the loss of potentially valuable information.To address these issues,we propose an enhancing entity and relation extraction with high-quality spans and enhanced marker(HSEM)strategies,it assigns adaptive weights to different spans in order to make the model more focused on high quality spans.Specifically,the HSEM model enriches marker representation to incorporate more span information and enhance entity categorization.Additionally,we design a span scoring framework that assesses span quality based on the fusion of internal information and focuses the model on training high-quality samples to improve performance.Experimental results on six benchmark datasets demonstrate that our model achieves state-of-the-art results after discriminating span quality. 展开更多
关键词 High-quality spans enhanced marker span scoring framework span representations entity and relation extraction
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面向生态补偿的水净化生态系统服务供需流动的空间耦合研究——以长三角生态绿色一体化示范区为例 被引量:2
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作者 陈昊扬 姚申君 +2 位作者 彭婉婷 蔡文博 蔡永立 《生态学报》 北大核心 2025年第7期3079-3091,共13页
深入探讨了长三角生态绿色一体化发展示范区(简称“示范区”)内水净化生态系统服务(WPS)的供需状况、服务流动路径及其与生态补偿的关系。随着工业化和城市化的快速推进,示范区面临着严峻的水资源污染和生态系统退化挑战。针对这些问题... 深入探讨了长三角生态绿色一体化发展示范区(简称“示范区”)内水净化生态系统服务(WPS)的供需状况、服务流动路径及其与生态补偿的关系。随着工业化和城市化的快速推进,示范区面临着严峻的水资源污染和生态系统退化挑战。针对这些问题,首先采用InVEST模型对示范区内氮磷WPS的供需进行了量化分析,揭示了不同子流域和行政区域间的供需差异。研究结果显示,示范区大部分地区存在显著的WPS供需赤字,尤其是在太湖东南侧、示范区西南角和东北角区域,氮磷净化服务的供需矛盾尤为突出。为进一步理解WPS的流动特性,应用了SPANS算法来模拟服务在示范区内的流动路径。分析发现,服务盈余区域主要集中在示范区的中心地带以及吴江区的北部和东南部。这些区域通过生态服务流动有效缓解了周边地区的污染压力,形成了明显的区域生态优势。然而,流动路径的复杂性也揭示了生态服务在不同地区间分配的不均衡性,强调了进行合理生态补偿的重要性。基于供需流动分析结果,提出了示范区生态补偿的优化策略。应优先补偿那些接收大量外来污染负荷、提供重要WPS的区域,确保这些区域能够持续提供高质量的生态系统服务。通过政策支持和财政援助,引导资金和资源流向具有潜在供应能力的区域,增强其生态系统功能。研究还建议引入基于供需流动态监测的补偿调整,以应对区域生态服务变化的不确定性,确保生态补偿政策的精准性和有效性。研究不仅为示范区WPS的供需状况提供了全面的量化分析,还通过流动路径模拟和生态补偿设计,为区域生态治理和可持续发展提供了科学依据和实践路径。这些成果对于改善示范区水生态环境、优化水资源配置、推动生态文明建设具有重要意义,同时也为其他地区类似问题的解决提供了有益参考。 展开更多
关键词 水净化服务 生态系统服务流 供需空间关联 生态补偿 spans算法 长三角生态绿色一体化示范区
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Span 80-P507体系萃取稀土防止乳化试验研究
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作者 张秋露 刘杰 +4 位作者 王志荣 薛志潇 李倩婷 高丽 张家起 《湿法冶金》 北大核心 2025年第3期388-397,共10页
溶剂萃取法是稀土分离提纯的主要方法之一,但在工业生产过程中常因工艺条件控制不当而发生乳化现象。为了解决这一难题,研究了以表面活性剂Span 80为调控剂、P507为萃取剂、煤油为稀释剂萃取稀土,考察了水相pH、搅拌速度和水油相比对Er^... 溶剂萃取法是稀土分离提纯的主要方法之一,但在工业生产过程中常因工艺条件控制不当而发生乳化现象。为了解决这一难题,研究了以表面活性剂Span 80为调控剂、P507为萃取剂、煤油为稀释剂萃取稀土,考察了水相pH、搅拌速度和水油相比对Er^(3+)萃取率和萃余液中油质量浓度的影响,并采用响应面法对工艺参数进行了优化。优化结果表明;在水相pH=3.5、搅拌速度130 r/min、水油相比4∶1优化条件下萃取5 min,Er^(3+)萃取率可达95.42%,萃余液中油质量浓度仅为1.68 mg/L,预测值与试验结果吻合度较高;加入Span 80能有效防止乳化现象发生,调控作用明显。 展开更多
关键词 P507 Span 80 稀土 溶剂萃取 乳化 响应面法
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基于span机制与动态解码策略的中文敏感信息识别方法
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作者 钱明熙 梁颖红 《金陵科技学院学报》 2025年第1期15-21,共7页
数字技术的快速发展导致中文敏感信息泄露风险加剧,而传统基于匹配规则和机器学习的方法在复杂实体边界和中文上下文处理时存在不足。针对中文敏感信息的命名实体识别问题提出了一种基于span机制和动态解码策略的改进模型,在BERT+BiLSTM... 数字技术的快速发展导致中文敏感信息泄露风险加剧,而传统基于匹配规则和机器学习的方法在复杂实体边界和中文上下文处理时存在不足。针对中文敏感信息的命名实体识别问题提出了一种基于span机制和动态解码策略的改进模型,在BERT+BiLSTM+CRF模型的基础上,加入span机制以更好地捕捉实体边界的位置信息。实验结果表明,相较于未加入span的基线模型,新模型的准确性和F1值显著提升,F1得分为96.7%,在处理长距离依赖关系和复杂实体时表现更加出色。 展开更多
关键词 中文敏感信息 命名实体识别 span机制 动态解码策略 上下文分析
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Span乳化稠油油水界面性能
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作者 唐珑 潘延东 +2 位作者 黄蒙 高荆维 张志秋 《化工科技》 2025年第5期21-26,50,共7页
针对油田注水开发中油井出水引发的低效循环问题,系统探究了原油组成性质对Span乳化稠油油水界面及其乳状液稳定性的影响。选取辽河油田2种稠油(1^(#)和2^(#))为研究对象,通过柱层析分离获得族组分,结合紫外光谱、红外光谱及气质联用技... 针对油田注水开发中油井出水引发的低效循环问题,系统探究了原油组成性质对Span乳化稠油油水界面及其乳状液稳定性的影响。选取辽河油田2种稠油(1^(#)和2^(#))为研究对象,通过柱层析分离获得族组分,结合紫外光谱、红外光谱及气质联用技术表征原油组成特征。实验采用单滴法评价界面膜强度,并借助偏光显微镜观察乳状液微观状态。结果表明,2^(#)原油沥青质+胶质含量显著高于1^(#)原油,其芳香烃组分中低环芳烃占比更高,利于沥青质分散及界面膜强化。系列Span乳化剂中Span80由于结构中的长碳链和双键结构使其在2^(#)原油体系中形成的界面膜强度最优(t1/2=333s)。微观分析表明,Span80/2^(#)体系形成的油包水(W/O)乳状液平均粒径较Span20体系明显减小,乳状液稳定性提高,Span乳化剂的结构对油水界面强度产生明显影响。 展开更多
关键词 乳化稠油 界面膜强度 Span乳化剂
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SPAN动态保证金模型下电力期货套期效果研究
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作者 苑秀娥 郝宇翔 《财会通讯》 北大核心 2025年第5期97-102,共6页
随着我国电力市场化不断推进,电力现货市场逐步放开,各区域电力现货市场加速转入正式运行。电力现货价格波动剧烈,需要开设电力期货商品发挥套期保值作用。电力期货是控制电力现货价格风险的重要金融衍生工具,期货保证金制度是期货商品... 随着我国电力市场化不断推进,电力现货市场逐步放开,各区域电力现货市场加速转入正式运行。电力现货价格波动剧烈,需要开设电力期货商品发挥套期保值作用。电力期货是控制电力现货价格风险的重要金融衍生工具,期货保证金制度是期货商品的核心制度,SPAN动态保证金系统下计算的动态保证金具备更强的风险控制能力。本文结合我国电力市场的特点,设计了电力期货动态保证金计算模型,运用套期会计分析了动态保证金模型下电力期货套期保值的效果,并为我国电力期货市场的建设提出建议。 展开更多
关键词 SPAN动态保证金系统 电力期货 套期会计
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Crossing latitude introduction delayed flowering and facilitated dry matter accumulation of soybean as a forage crop
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作者 Dong An Xingfa Lai +3 位作者 Tianfu Han Jean Marie Vianney Nsigayehe Guixin Li Yuying Shen 《Journal of Integrative Agriculture》 2025年第4期1436-1447,共12页
Grain soybean(Glycine max(L.)Merr.)shows potential as a forage crop following its introduction from low to high latitudes due to in its growth phenotype.However,the application of this approach is impeded by the diver... Grain soybean(Glycine max(L.)Merr.)shows potential as a forage crop following its introduction from low to high latitudes due to in its growth phenotype.However,the application of this approach is impeded by the diverse ecological types of soybean,their adaptability to the introduction,and the uncertainty surrounding the growth phenotype post-introduction.This study introduced 24 grain soybean varieties from low-latitude regions(22-31°N)to the high-latitude northwestern Loess Plateau(39°N)between 2018 and 2019.The growth phenotypes were observed,and their forage productivity potential was assessed.All varieties displayed delayed flowering following cross-latitude introduction,with the vegetative growth phase of some varieties even exceeding their entire growth duration at their origin.Rapid dry matter accumulation rates indicated growth adaptation performance and formed the basis for soybean forage yield.Varieties from the tropical South China region exhibited significant yield advantages,with dry matter yields of 8.97-14.68 t ha^(-1)and crude protein yields of 1.44-2.51 t ha^(-1).Varieties HX3 and GX7 from this region demonstrated optimal growth adaptability and productivity in the cross-latitude environment,achieving the highest dry matter yields of 14.68 and 13.86 t ha^(-1),respectively.As a result,HX3 and GX7 are recommended for local farming systems to provide high-quality forage.The cross-latitude introduction of soybean is proposed as a viable and efficient strategy for forage improvement and application. 展开更多
关键词 forage soybean latitude span vegetative growth INTRODUCTION variety screening
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Long-term effect of inbreeding in the yellow steppe lemming,Eolagurus luteus,captive colony
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作者 Vladimir V.Streltsov Olga G.Ilchenko Elena V.Kotenkova 《Current Zoology》 2025年第3期329-337,共9页
In the current research,we investigated the impact of gradually increasing inbreeding on the life span and reproductive rate of yellow steppe lemmings,Eolagurus luteus,that reproduced in the Moscow Zoo.The focal capti... In the current research,we investigated the impact of gradually increasing inbreeding on the life span and reproductive rate of yellow steppe lemmings,Eolagurus luteus,that reproduced in the Moscow Zoo.The focal captive colony existed from 2017 to 2021.The studied animals belonged to the second to tenth generations.The founders of the colony were 5 females and 5 males originating from 3 females and 4 males livetrapped in the Zaisan basin(Kazakhstan).The degree of their descendant relatedness progressively increased.The animals intended to be used for reproduction were distributed to pairs with unfamiliar partners.We constructed the pedigree of 177 individuals and calculated their inbreeding coefficients.This parameter varied from O to 0.29,and the maximum values were registered in the lemmings of the seventh to tenth generations.We measured the life span of 61 individuals and used information about the reproduction or its absence in 45 pairs.A substantial decline in individual life span and reproductive parameters in the breeding pairs,along with a progressive increase in the inbreeding coefficients,was registered.The number of delivered litters,born pups,and young lived up to the age of puberty significantly depended on the level of mother inbreeding.The noticeable traits of inbreeding depression in the colony appeared in 2019-2020 when the offspring inbreeding coefficients reached approximately 0.2.Therefore,we assume that if the E.luteus population originates from a relatively small number of noninbred and unfamiliar individuals,then successful reproduction without significant inbreeding depression will continue for several generations of offspring. 展开更多
关键词 ARVICOLINAE Eolagurus luteus inbreeding coefficient inbreeding depression life span reproductive parameters
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Life Span of Solutions for a Class of Semilinear Parabolic Equations with Large Initial Values
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作者 XUE Yingzhen LI Yulin 《Wuhan University Journal of Natural Sciences》 2025年第2期111-117,共7页
In this paper,a class of semilinear parabolic equations with cross coupling of power and exponential functions and large initial values are studied.By constructing and solving ordinary differential equations,the upper... In this paper,a class of semilinear parabolic equations with cross coupling of power and exponential functions and large initial values are studied.By constructing and solving ordinary differential equations,the upper and lower bounds on the solution life span of the equations areobtained. 展开更多
关键词 semilinear parabolic equations life span comparative principle blow up
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灵活运用保证金模型 防范金融衍生品交易风险
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作者 王昉 《中国外资》 2025年第4期89-91,共3页
保证金模型在金融衍生品交易中占据核心地位,是风险管理的重要工具。它包含策略性模式、SPAN模式和TIMS模式等多种形态,每种模式都有其独特的应用场景和优势。在金融衍生品交易中,保证金模型通过资金管理、止损策略、分散投资以及风险... 保证金模型在金融衍生品交易中占据核心地位,是风险管理的重要工具。它包含策略性模式、SPAN模式和TIMS模式等多种形态,每种模式都有其独特的应用场景和优势。在金融衍生品交易中,保证金模型通过资金管理、止损策略、分散投资以及风险评估和监控等多维度应用,为交易者提供了有效的风险控制手段。这些应用不仅帮助交易者降低风险、优化资源配置,还增强了市场的稳定性和透明度,促进了金融衍生品市场的健康发展。 展开更多
关键词 SPAN模式 TIMS模式 止损策略 策略性模式 风险评估
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A new theory for determining large deformation area of roof at intersection and verification analysis
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作者 WU Yi-yi GAO Yu-bing +2 位作者 MA Xiang ZHANG Xing-xing HE Man-chao 《Journal of Central South University》 2025年第2期656-677,共22页
The intersection is a widely used traffic line structure from the shallow tunnel to the deep roadway,and determining the subsidence hidden danger area of the roof is the key to its stability control.However,applying t... The intersection is a widely used traffic line structure from the shallow tunnel to the deep roadway,and determining the subsidence hidden danger area of the roof is the key to its stability control.However,applying traditional maximum equivalent span beam(MESB)theory to determine deformation range,peak point,and angle influence poses a challenge.Considering the overall structure of the intersection roof,the maximum equivalent triangular plate(METP)theory is proposed,and its geometric parameter calculation formula and deflection calculation formula are obtained.The application of the two theories in 18 models with different intersection angles,roadway types,and surrounding rock lithology is verified by numerical analysis.The results show that:1)The METP structure of the intersection roof established by the simulation results of each model successfully determined the location of the roof’s high displacement zone;2)The area comparison method of the METP theory can be reasonably explained:①The roof subsidence of the intersection decreases with the increase of the intersection angle;②The roof subsidence at the intersection of different roadway types has a rectangular type>arch type>circular type;③The roof subsidence of the intersection with weak surrounding rock is significantly larger than that of the intersection with hard surrounding rock.According to the application results of the two theories,the four advantages of the METP theory are compared and clarified in the basic assumptions,mechanical models,main viewpoints,and mechanism analysis.The large deformation inducement of the intersection roof is then explored.The J 2 peak area of the roof drives the large deformation of the area,the peak point of which is consistent with the center of gravity position of the METP.Furthermore,the change in the range of this peak is consistent with the change law of the METP’s area.Hence,this theory clarifies the large deformation area of the intersection roof,which provides a clear guiding basis for its initial support design,mid-term monitoring,and late local reinforcement. 展开更多
关键词 roadway intersection roof deformation equivalent span theory triangular plate structure numerical analysis stress partial tensor
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Incommensurate modulated structure and its influence on the martensitic transformation temperature span of single phase multielement Ni-Cu-Co-Mn-Ga two-way shape memory single crystals
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作者 Qijia Yu Yang Liu +5 位作者 Chen Si Wenjia Wang Jiaxi Meng Jingmin Wang Jinghua Liu Chengbao Jiang 《Journal of Materials Science & Technology》 2025年第5期230-240,共11页
Significant two-way shape memory effect(TWSME)was achieved in single crystals of single-phase multielement Ni42-x Cu8 Cox Mn37 Ga13(8≤x≤12)alloys by performing thermomechanical training.However,anomalous dependence ... Significant two-way shape memory effect(TWSME)was achieved in single crystals of single-phase multielement Ni42-x Cu8 Cox Mn37 Ga13(8≤x≤12)alloys by performing thermomechanical training.However,anomalous dependence of the martensitic transformation temperature span on Co content was observed.Before training,quite a narrow temperature span of the martensitic transformation,nearly independent of the Co content,was observed in all single crystals.After training the temperature span was still narrow for 8≤x≤10.9 but was obviously expanded for 10.9<x≤12.High-resolution transmission electron microscopy revealed that at the atomic scale,there exists incommensurate modulated structure in the single phase single crystals,as evidenced by nonperiodic satellite spots in the selected area electronic diffraction patterns.Moreover,the modulated wave vector of the satellite spots was increased by higher Co contents.Combining first principal calculations it was considered that the incommensurate modulated structure originates from the formation of Co-Co pairs.After training arrays of ordered dislocations with the same Burgers vector were introduced for 8≤x≤10.9 but the network of dislocations was formed for 10.9<x≤12.Based on analysis of transmission electron microscopy,geometric phase,thermodynamics,and Landau theory,it was considered that the austenite/martensite phase interface was pinned by the network of dislocations,expanding the temperature span of the martensitic transformation.This work supplies new insights for understanding the microstructure and martensitic transformation of Ni-Mn-Ga-based alloys. 展开更多
关键词 Martensitic transformation Incommensurate modulated structure Temperature span DISLOCATION Two-way shape memory effect
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Experimental Design and Material Properties Research of the Reinforced UHPC Columns
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作者 Jiaqi Duan Qiaoling Fu 《Journal of World Architecture》 2025年第4期28-34,共7页
Medium shear span ratio reinforced columns are prone to complex failure under seismic action.This paper compares the seismic performance of normal concrete columns and UHPC columns by introducing ultra-high-performanc... Medium shear span ratio reinforced columns are prone to complex failure under seismic action.This paper compares the seismic performance of normal concrete columns and UHPC columns by introducing ultra-high-performance concrete(UHPC).The shear span ratio(2.4-4.4)and axial compression ratio(0.10,0.36)were used as variables,and the bearing capacity,ductility and failure mode were analyzed through low-cycle reciprocating loading studys.The results showed that UHPC significantly improved the bearing capacity,stiffness and energy dissipation capacity of the column,and suppressed the crushing and spalling of concrete.When the shear span ratio is 2.4 and the axial compression ratio is 0.36,the failure mode of UHPC columns was changed from shear failure to flexural shear failure.Thus this study can become a reference for the seismic design of UHPC columns. 展开更多
关键词 Medium shear span ratio UHPC Low-cycle reciprocating study Shear failure Axial compression ratio
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Actionable Genotypes and Their Association with Life Span in Iceland
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作者 Brynjar O Jensson 《四川生理科学杂志》 2025年第11期2486-2486,共1页
Background:In 2021,the American College of Medical Genetics and Genomics(ACMG)recommended reporting actionable genotypes in 73 genes associated with diseases for which preventive or therapeutic measures are available.... Background:In 2021,the American College of Medical Genetics and Genomics(ACMG)recommended reporting actionable genotypes in 73 genes associated with diseases for which preventive or therapeutic measures are available.Evaluations of the association of actionable genotypes in these genes with life span are currently lacking.Methods:We assessed the prevalence of coding and splice variants in genes on the ACMG Secondary Findings,version 3.0(ACMG SF v3.0),list in the genomes of 57,933 Icelanders.We assigned pathogenicity to all reviewed variants using reported evidence in the ClinVar database,the frequency of variants,and their associations with disease to create a manually curated set of actionable genotypes(variants).We assessed the relationship between these genotypes and life span and further examined the specific causes of death among carriers. 展开更多
关键词 Icelandic population genetic variants PATHOGENICITY life span coding splice variants actionable genotypes preventive therapeutic measures ACMG secondary findings
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Construction Process of Basement Floor Slab in Building Engineering Construction
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作者 Kaiyuan Tian 《Journal of World Architecture》 2025年第4期73-78,共6页
The basement was located at the bottom of the building,which not only affected the quality of the whole construction project but also had special requirements for construction technology and construction requirements.... The basement was located at the bottom of the building,which not only affected the quality of the whole construction project but also had special requirements for construction technology and construction requirements.In modern times,with the increasing height of the building,the pressure on the ground has grown,and the demands for basements in construction projects have also steadily increased.With the development of modern technology,various construction techniques for basements emerged within the construction industry.Thus,this paper analyses the type of basement floor construction technologies,highlighting the application of these methods,and points out critical issues to consider.By examining frequent basement leakage problems,the paper proposed several measures to improve the quality if basement construction,aiming to better protect the service life of the building and further improve overall quality,and offering valuable insights for future projects. 展开更多
关键词 Construction engineering Basement slab construction Building life span
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