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相对类反义性质形容词作补语的不对称
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作者 郝玲 《阜阳师范学院学报(社会科学版)》 2012年第5期41-43,共3页
"大小""好坏""冷热"三类反义形容词做补语时与谓语动词组合情况各不相同,当谓语是强方向动词时,只与三类反义词的一方组合,并且只能实比不能虚比;当谓语是弱方向动词时,"好坏"类作补语双方都... "大小""好坏""冷热"三类反义形容词做补语时与谓语动词组合情况各不相同,当谓语是强方向动词时,只与三类反义词的一方组合,并且只能实比不能虚比;当谓语是弱方向动词时,"好坏"类作补语双方都可以实比,"好"方表积极意义的可以虚比,"坏"方表消极意义的不能虚比;"大小"类双方都既能实比又能虚比;"冷热"类双方都能实比,但不能虚比。 展开更多
关键词 相对类 强方向动词 弱方向动词 不对称
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基于相对密度聚类的激光点云电力线提取方法研究
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作者 胡柏平 《中文科技期刊数据库(全文版)工程技术》 2024年第2期0145-0148,共4页
为进一步降低环境参数对于电力线点云产生的影响,为电力线巡检与相关规划工作的开展提供更加准确可靠的参考依据,本文以当下电力线提取技术存在的主要问题作为切入点,基于候选点云筛选、单根电力线提取以及散点拟合与检测等角度对相对... 为进一步降低环境参数对于电力线点云产生的影响,为电力线巡检与相关规划工作的开展提供更加准确可靠的参考依据,本文以当下电力线提取技术存在的主要问题作为切入点,基于候选点云筛选、单根电力线提取以及散点拟合与检测等角度对相对密度聚类下线路点云数据获取方法进行了阐述,同时以某500kV电力线走廊点云数据分析项目为例,对上述方法进行了相应验证,力求为从业者提供参考。 展开更多
关键词 相对密度聚 激光雷达 点云数据 电力线提取
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相对熵模糊C均值聚类分割算法 被引量:2
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作者 田小平 张忠宝 吴成茂 《西安邮电大学学报》 2015年第5期38-42,61,共6页
针对模糊C均值聚类分割算法无法获得复杂图像的细节信息问题,提出一种相对熵模糊C均值聚类分割算法。该算法利用划分隶属度构造相对熵,对传统模糊C均值聚类进行正则化约束,将其作为正则化因子添加到传统FCM的目标函数,得到新的聚类目标... 针对模糊C均值聚类分割算法无法获得复杂图像的细节信息问题,提出一种相对熵模糊C均值聚类分割算法。该算法利用划分隶属度构造相对熵,对传统模糊C均值聚类进行正则化约束,将其作为正则化因子添加到传统FCM的目标函数,得到新的聚类目标函数。通过拉格朗日乘子最优化推导,得到新的隶属度和聚类中心的迭代更新表达式。实验结果表明,该算法对于图像与背景灰度相近的复杂图像可以清晰的分割出图像的轮廓,也比FCM方法获得更多的图像细节信息。 展开更多
关键词 图像分割 模糊C均值聚 相对熵模糊C均值聚 细节信息
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关于相对Bousfield类和相对Bousfield等价关系
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作者 黄文林 《数学杂志》 2021年第3期257-269,共13页
本文研究了有限群的群代数上的有限生成模的相对Bousfield类,定义了相对Bousfield等价关系和相对Bousfield等价类,建立了群与子群的相对Bousfield等价类之间的对应关系.
关键词 群代数 相对Bousfield 相对Bousfield等价 相对投射
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基于相对密度聚类的激光点云电力线提取方法 被引量:2
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作者 温玉维 邓长勇 +1 位作者 曾德培 翁向阳 《测绘与空间地理信息》 2022年第8期262-264,共3页
针对电力线点云聚类过程极易受参数影响的缺点,本文提出了一种基于相对密度聚类的激光点云电力线提取方法。该方法根据电力线点云数据维度与方向特征,实现电力线点云过滤;在把样本点按相对密度聚类成数据簇后,以最小二乘法拟合重构单个... 针对电力线点云聚类过程极易受参数影响的缺点,本文提出了一种基于相对密度聚类的激光点云电力线提取方法。该方法根据电力线点云数据维度与方向特征,实现电力线点云过滤;在把样本点按相对密度聚类成数据簇后,以最小二乘法拟合重构单个电力线,并引入均方根误差(RMSE)法,检验拟合后各目标簇电力线是否达到独立聚类的要求。在近邻参数7<K<10时,较DBSCAN聚类提取法,相对密度聚类提取法能更精准地实现单个电力线的分离。该算法为解决在复杂环境中精准提取电力线的难题,提供了新的研究思路。 展开更多
关键词 激光点云 相对密度聚 K-近邻参数 电力线提取
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支持向量域多分类器 被引量:6
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作者 吴德 刘三阳 《西安交通大学学报》 EI CAS CSCD 北大核心 2012年第6期87-91,共5页
为解决多分类支持向量机计算量大、训练时间长的问题,构造了支持向量域多分类器(MS-VDC).在训练阶段,运用支持向量域描述求得各类样本的最小包围超球,进而将数据空间划分为不同区域;在测试阶段,计算待识别样本与最小包围超球球心的距离... 为解决多分类支持向量机计算量大、训练时间长的问题,构造了支持向量域多分类器(MS-VDC).在训练阶段,运用支持向量域描述求得各类样本的最小包围超球,进而将数据空间划分为不同区域;在测试阶段,计算待识别样本与最小包围超球球心的距离,并判断其空间位置;对超球重叠以及超球外区域的样本,定义一种相对类距离,判断样本归属该值较小的类.MSVDC避免了重复利用训练样本,降低了内存占用并提高了计算效率.数值实验结果表明:MSVDC具有好的鲁棒性,分类精度可高达98.89%,分别比一对多和一对一算法高4.51%和1.24%,训练时间分别为一对多和一对一算法的18.06%和55.41%. 展开更多
关键词 多分 支持向量域描述 最小包围超球 相对类距离 空间位置
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基于密度聚类的K近邻法在储层流体识别中的应用 被引量:11
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作者 赵军 卢一凡 +1 位作者 李宗杰 柳建华 《中国石油大学学报(自然科学版)》 EI CAS CSCD 北大核心 2015年第5期65-71,共7页
针对传统储层流体识别方法识别精度低、运算量大、过于依赖个人经验的缺点,提出基于密度聚类的K近邻法,根据待测层段测井数据的空间分布规律,将样本按相对密度聚类成数据簇,并利用K近邻投票获得各簇所属类别。将该方法应用在某油田奥陶... 针对传统储层流体识别方法识别精度低、运算量大、过于依赖个人经验的缺点,提出基于密度聚类的K近邻法,根据待测层段测井数据的空间分布规律,将样本按相对密度聚类成数据簇,并利用K近邻投票获得各簇所属类别。将该方法应用在某油田奥陶系鹰山组碳酸盐岩储层识别中。结果表明,较之其他常用识别方法,该算法识别精度高,泛化性和鲁棒性强,在处理大数据分类问题时具有明显优势,且在识别常规方法难以识别的油水同层时取得了较好的效果,具有良好的应用前景,为利用数据挖掘方法解决油田勘探开发中的复杂问题提供了新思路。 展开更多
关键词 测井解释 流体识别 K近邻法 相对密度聚 数据挖掘
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不同的K-means聚类算法比较研究 被引量:2
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作者 袁健斌 樊宇翊 伍兴国 《电子技术与软件工程》 2020年第21期175-177,共3页
本文按照相似度的不同选择将聚类分为绝对聚类和相对聚类,总结了初始点的选择方法,并分析和比较K-means聚类的三种不同算法:Forgy/Lloyd算法,MacQueen算法和Hartigan&Wong算法的异同点。
关键词 算法 K-MEANS 相对 绝对聚 机器学习
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基于相对优势类差量的序信息系统属性约简算法 被引量:8
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作者 吕跃进 韦碧鹏 胡明明 《模糊系统与数学》 CSCD 北大核心 2013年第1期142-148,共7页
针对序信息系统,定义了优势类差量和相对优势类差量,讨论了一种刻画属性重要度的新指标。在此基础上,提出一种基于相对优势类差量的启发式约简算法,它能从搜索空间中删除不重要属性,降低了约简的时间复杂度。与现有启发式约简算法相比,... 针对序信息系统,定义了优势类差量和相对优势类差量,讨论了一种刻画属性重要度的新指标。在此基础上,提出一种基于相对优势类差量的启发式约简算法,它能从搜索空间中删除不重要属性,降低了约简的时间复杂度。与现有启发式约简算法相比,该算法具有较高的搜索效率。实例与实验表明了该算法的可行性与有效性。 展开更多
关键词 粗糙集理论 序信息系统 优势差量 相对优势差量 属性约简
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除草剂精克草能对烟田节肢动物群落的影响 被引量:19
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作者 巫厚长 魏重生 +1 位作者 蒯文兴 程遐年 《安徽农业大学学报》 CAS CSCD 北大核心 2001年第4期372-375,共4页
本试验研究了施用除草剂对烟田节肢动物群落的影响。结果表明 ,施药区植食类相对丰盛度明显增加 ,尤其是蚜科 ,捕食类相对丰盛度明显减少 ,特别是蜘蛛类的皿蛛科 ;节肢动物群落和植食类亚群落的多样性指数和均匀度降低 。
关键词 除草剂 烟田 节肢动物群落 精克草能 捕食相对丰盛度
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一种新的基于特殊离群样本优化的三维点云特征选择算法 被引量:2
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作者 黄祥 王红星 +2 位作者 顾徐 孟悦 王浩羽 《图学学报》 CSCD 北大核心 2022年第5期884-891,共8页
随着元宇宙、数字孪生、虚拟现实与增强现实等前沿技术的快速发展,三维点云在电力、建筑、先进制造等行业中得到广泛应用,随之而来的,如何降低三维点云数据冗余度、有效进行点云特征选择,已在充分利用海量点云数据中扮演着关键角色。考... 随着元宇宙、数字孪生、虚拟现实与增强现实等前沿技术的快速发展,三维点云在电力、建筑、先进制造等行业中得到广泛应用,随之而来的,如何降低三维点云数据冗余度、有效进行点云特征选择,已在充分利用海量点云数据中扮演着关键角色。考虑到现有大多数三维点云特征选择算法忽略了特定样本在特征评估中的表现,提出一种新的有监督特征选择算法,即基于特殊离群样本优化的特征选择算法(FSSO)。具体地,为获得精准的特殊离群样本(SOs),FSSO优化均值中心并动态地界定类簇主体;计算SOs的类内相对偏离程度,通过减小类内相对偏离对特征进行打分,实现特征选择过程。在3个公共的三维点云模型分类数据集上(ModelNet40,IntrA,ShapeNetCore)的实验,以及4个高维人工特征数据集的验证实验结果表明,相较于其他特征选择算法,FSSO可选择出具有更强分类能力的特征子集,并提升分类准确率。 展开更多
关键词 三维点云数据 有监督特征选择 特殊离群样本 相对偏离程度
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Action Recognition from a Different View 被引量:1
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作者 陈昌红 干宗良 《China Communications》 SCIE CSCD 2013年第12期139-148,共10页
In this paper,we propose a novel approach to recognise human activities from a different view.Although appearance-based recognition methods have been shown to be unsuitable for action recognition for varying views,the... In this paper,we propose a novel approach to recognise human activities from a different view.Although appearance-based recognition methods have been shown to be unsuitable for action recognition for varying views,there must be some regularity among the same action sequences of different views.Selfsimilarity matrices appear to be relative stable across views.However,the ability to effectively realise this stability is a problem.In this paper,we extract the shape-flow descriptor as the low-level feature and then choose the same number of key frames from the action sequences.Self-similarity matrices are obtained by computing the similarity between any pair of the key frames.The diagonal features of the similarity matrices are extracted as the highlevel feature representation of the action sequence and Support Vector Machines(SVM) is employed for classification.We test our approach on the IXMAS multi-view data set.The proposed approach is simple but effective when compared with other algorithms. 展开更多
关键词 action recognition different view shape-flow descriptor self-similarity matrix diagonal feature
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Global Plate Motions and Their Impact on the Earth's Surface Area Change 被引量:1
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作者 Cao Shuai Zhang Keliang Wei Dongping 《Earthquake Research in China》 2010年第3期344-352,共9页
Based on their Euler poles, we calculated the relative velocities between every two plates in the typical global plate motion models, respectively, and estimated the area change along these boundaries. In our calculat... Based on their Euler poles, we calculated the relative velocities between every two plates in the typical global plate motion models, respectively, and estimated the area change along these boundaries. In our calculations, plates on both sides accommodated area changes depending on the boundary types: extensional, convergent or transform, so we can estimate area change of each plate and then globally. Our preliminary results show that the area of the southern hemisphere increased while that of the northern hemisphere decreased over the past I million years, and global area has increased by 26,000km^2 to 36,000km^2, which corresponds to the 160m - 250m increment on the Earth's radius if all these area increments are attributed to Earth's expansion. Taking the NUVEL-1 model as an example, of the 14 plates in this model, 11 are decreasing, but the global area has increased because of the larger increment amount from Africa, North America and Antarctica. Finally, we also discussed factors affecting the global area change such as subduction zone retreating and back-arc spreading. 展开更多
关键词 Plate Motions NUVEL-1 Model Pacific Plate SUBDUCTION
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A Multi-Hop Moving Zone(MMZ) Clustering Scheme Based on Cellular-V2X 被引量:3
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作者 Zahid Khan Pingzhi Fan 《China Communications》 SCIE CSCD 2018年第7期55-66,共12页
A clustering scheme based on pure V2V communications has two prominent issues i.e. broadcast storm and network disconnection. The application of the fifth generation(5G) technology to vehicular networks is an optimal ... A clustering scheme based on pure V2V communications has two prominent issues i.e. broadcast storm and network disconnection. The application of the fifth generation(5G) technology to vehicular networks is an optimal choice due to its wide coverage and low latency features. In this paper, a Multihop Moving Zone(MMZ) clustering scheme is proposed by combining IEEE 802.11p with the 3rd Generation Partnership Project(3GPP) 5G cellular technology. In MMZ, vehicles are clustered up-to three hops using V2V communications based on IEEE 802.11 p aiming to reduce excessive cellular hand-off cost. While the zonal heads(ZHs) i.e. cluster heads(CHs) are selected by cellular-V2X(C-V2X) on the basis of multi-metrics i.e. relative speed, distance and link life time(LLT). The main goal of MMZ is to form stable clusters achieving high packet delivery and low latency. The simulation results using ns3 show that, 5G wide range technology significantly improves the stability of MMZ in term of ZH duration and change rate. The average Data Packet Delivery Ratio(DPDR) and E2E latency are also improved as compared to the existing clustering schemes. 展开更多
关键词 clustering 3GPP 5G cluster head stable clusters reliability and latency
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电动机效率测量不确定度评定
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作者 傅万进 黄和平 朱健军 《机电信息》 2011年第21期117-118,共2页
根据三相异步电动机能效等级确定方法E1法,建立了电动机效率的不确定度分析模型,并给出了计算方法。在此基础上,利用实测数据进行计算,得到了电机效率测量不确定度。
关键词 电动机效率 A不确定度 B标准不确定度 相对B不确定度 扩展不确定度
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Classification of Teleparallel Homothetic Vector Fields in Cylindrically Symmetric Static Space-Times in Teleparallel Theory of Gravitation
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作者 Ghulam Shabbir Suhail Khan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期675-678,共4页
In this paper we classify cylindrically symmetric static space-times according to their teleparallel homothetic vector fields using direct integration technique. It turns out that the dimensions of the teleparallel ho... In this paper we classify cylindrically symmetric static space-times according to their teleparallel homothetic vector fields using direct integration technique. It turns out that the dimensions of the teleparallel homothetic vector fields are 4, 5, 7 or 11, which are the same in numbers as in general relativity. In case of 4, 5 or 7 proper teleparallel homothetic vector fields exist for the special choice to the space-times. In the case of 11 teleparallel homothetic vector fields the space-time becomes Minkowski with all the zero torsion components. Teleparallel homothetic vector fields in this case are exactly the same as in general relativity. It is important to note that this classification also covers the plane symmetric static space-times. 展开更多
关键词 teleparallel homothetic vector fields WeitzenbSck connections TORSION
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Doppler shift based stable clustering scheme for mobile ad hoc networks
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作者 Ni Minming Zhong Zhangdui +1 位作者 Chen Ruifeng Zhao Dongmei 《High Technology Letters》 EI CAS 2011年第4期414-420,共7页
This paper addresses the clustering problem for mobile ad hoc networks. In the proposed scheme, Doppler shift associated with received signals is used to estimate the relative speed between aelnster head and its membe... This paper addresses the clustering problem for mobile ad hoc networks. In the proposed scheme, Doppler shift associated with received signals is used to estimate the relative speed between aelnster head and its members. With the estimated speed, a node can predict its stay time in every nearby cluster. In the initial clustering stage, a node joins a duster that can provide it with the longest stay time in order to reduce the number of re-affiliations. In the cluster maintaining stage, strategies are designed to help node cope with connection break caused by channel fading and node mobility. Simulation results show that the proposed clustering scheme can reduce the number of re-affiliations and the average disconnection time compared with previous schemes. 展开更多
关键词 mobile ad hoc network CLUSTERING doppler shift relative speed estimation
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Classification of Kantowski-Sachs and Bianchi Type Ⅲ Space-Times According to Their Killing Vector Fields in Teleparallel Theory of Gravitation
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作者 Ghulam Shabbir Suhail Khan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第9期469-472,共4页
In this paper we classify Kantowski-Sachs and Bianchi type Ⅲ space-times according to their teleparallel Killing vector fields using direct integration technique. It turns out that the dimension of the telepaxallel K... In this paper we classify Kantowski-Sachs and Bianchi type Ⅲ space-times according to their teleparallel Killing vector fields using direct integration technique. It turns out that the dimension of the telepaxallel Killing vector fields are 4 or 6, which are the same in numbers as in general relativity. In case of 4 the teleparallel Killing vector fields are multiple of the corresponding Killing vector fields in general relativity by some function of t. In the case of 6 Killing vector fields the metric functions become constants and the Killing vector fields in this case are exactly the same as in general relativity. Here we also discuss the Lie algebra in each case. 展开更多
关键词 teleparallel killing vector fields Weitzenb5ck connections TORSION
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A Note on Classification of Spatially Homogeneous Rotating Space-Times According to Their Teleparallel Killing Vector Fields in Teleparallel Theory of Gravitation
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作者 Ghulam Shabbir Suhail Khan Amjad Ali 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第2期268-272,共5页
In this paper we classify spatially homogeneous rotating space-times according to their teleparallel Killing vector fields using direct integration technique.It turns out that the dimension of the teleparallel Killing... In this paper we classify spatially homogeneous rotating space-times according to their teleparallel Killing vector fields using direct integration technique.It turns out that the dimension of the teleparallel Killing vector fields is 5 or 10.In the case of 10 teleparallel Killing vector fields the space-time becomes Minkowski and all the torsion components are zero.Teleparallel Killing vector fields in this case are exactly the same as in general relativity.In the cases of 5 teleparallel Killing vector fields we get two more conservation laws in the teleparallel theory of gravitation.Here we also discuss some well-known examples of spatially homogeneous rotating space-times according to their teleparallel Killing vector fields. 展开更多
关键词 teleparallel killing vector fields Weitzenbock geometry TORSION
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Simultaneous determination of five phenylethanoid glycosides in Cistanches Herba using quantitative analysis of multi-components by single marker 被引量:9
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作者 Ruiyan Li Mingbo Zhao +1 位作者 Pengfei Tu Yong Jiang 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2019年第8期537-546,共10页
In the present study, a method for the quantitative analysis of multi-components by single marker(QAMS) has been developed and validated for the simultaneous determination of echinacoside(ECH), tubuloside A, acteoside... In the present study, a method for the quantitative analysis of multi-components by single marker(QAMS) has been developed and validated for the simultaneous determination of echinacoside(ECH), tubuloside A, acteoside, isoacteoside, and2’-acetylacteoside in Cistanches Herba. ECH was used as the internal standard(IS) to obtain the relative correction factors(RCFs) of the other four phenylethanoid glycosides(PhGs);meanwhile, various influencing factors on RCFs were investigated under different conditions. The content of each component was calculated with RCF. The results were compared with those obtained by the external standard method(ESM) to verify the feasibility and accuracy of the established QAMS method. No significant difference was found in the quantitative results of 10 batches of Cistanches Herba between QAMS and ESM. The proposed QAMS method for simultaneous determination of PhGs in Cistanches Herba is accurate and feasible, providing an efficient and economical approach for the quality control of Cistanches Herba. 展开更多
关键词 Cistanches Herba Phenylethanoid glycosides Quantitative analysis of multi-components by single-marker Relative correction factors
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