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Infrared small target detection algorithm via partial sum of the tensor nuclear norm and direction residual weighting
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作者 SUN Bin XIA Xing-Ling +1 位作者 FU Rong-Guo SHI Liang 《红外与毫米波学报》 北大核心 2025年第2期277-288,共12页
Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small targe... Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small target detection method based on the tensor nuclear norm and direction residual weighting was proposed.Based on converting the infrared image into an infrared patch tensor model,from the perspective of the low-rank nature of the background tensor,and taking advantage of the difference in contrast between the background and the target in different directions,we designed a double-neighborhood local contrast based on direction residual weighting method(DNLCDRW)combined with the partial sum of tensor nuclear norm(PSTNN)to achieve effective background suppression and recovery of infrared small targets.Experiments show that the algorithm is effective in suppressing the background and improving the detection ability of the target. 展开更多
关键词 infrared small target detection infrared patch tensor model partial sum of the tensor nuclear norm direction residual weighting
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Bayesian Network Reconstruction and Iterative Divergence Problem Solving Method Based on Norm Minimization
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作者 Kuo Li Aimin Wang +2 位作者 Limin Wang Yuetan Zhao Xinyu Zhu 《Computer Modeling in Engineering & Sciences》 2025年第4期617-637,共21页
A Bayesian network reconstruction method based on norm minimization is proposed to address the sparsity and iterative divergence issues in network reconstruction caused by noise and missing values.This method achieves... A Bayesian network reconstruction method based on norm minimization is proposed to address the sparsity and iterative divergence issues in network reconstruction caused by noise and missing values.This method achieves precise adjustment of the network structure by constructing a preliminary random network model and introducing small-world network characteristics and combines L1 norm minimization regularization techniques to control model complexity and optimize the inference process of variable dependencies.In the experiment of game network reconstruction,when the success rate of the L1 norm minimization model’s existence connection reconstruction reaches 100%,the minimum data required is about 40%,while the minimum data required for a sparse Bayesian learning network is about 45%.In terms of operational efficiency,the running time for minimizing the L1 normis basically maintained at 1.0 s,while the success rate of connection reconstruction increases significantly with an increase in data volume,reaching a maximum of 13.2 s.Meanwhile,in the case of a signal-to-noise ratio of 10 dB,the L1 model achieves a 100% success rate in the reconstruction of existing connections,while the sparse Bayesian network had the highest success rate of 90% in the reconstruction of non-existent connections.In the analysis of actual cases,the maximum lift and drop track of the research method is 0.08 m.The mean square error is 5.74 cm^(2).The results indicate that this norm minimization-based method has good performance in data efficiency and model stability,effectively reducing the impact of outliers on the reconstruction results to more accurately reflect the actual situation. 展开更多
关键词 Bayesian norm minimization network reconstruction iterative divergence SPARSITY
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Commentary on“International norms for adult handgrip strength:A systematic review of data on 2.4 million adults aged 20 to 100+years from 69 countries and regions”
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作者 Barbara E.Ainsworth Zhining Zhou 《Journal of Sport and Health Science》 2025年第4期40-42,共3页
In the December 2025 issue of the Journal of Sport and Health Science,Tomkinson et al.^(1)present international norms for adult handgrip strength(HGS)developed from a systematic review of 100 studies with 2.4 million ... In the December 2025 issue of the Journal of Sport and Health Science,Tomkinson et al.^(1)present international norms for adult handgrip strength(HGS)developed from a systematic review of 100 studies with 2.4 million adults aged 20 to 100+years from 69 countries and regions.Twenty-eight interna-tional handGRIP Strength(iGRIPS)researchers contributed to the study. 展开更多
关键词 handgrip strength systematic review ADULTS international norms
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Schweizer-Sklar T-Norm Operators for Picture Fuzzy Hypersoft Sets: Advancing Suistainable Technology in Social Healthy Environments
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作者 Xingsi Xue Himanshu Dhumras +2 位作者 Garima Thakur Rakesh Kumar Bajaj Varun Shukla 《Computers, Materials & Continua》 2025年第7期583-606,共24页
Ensuring a sustainable and eco-friendly environment is essential for promoting a healthy and balanced social life.However,decision-making in such contexts often involves handling vague,imprecise,and uncertain informat... Ensuring a sustainable and eco-friendly environment is essential for promoting a healthy and balanced social life.However,decision-making in such contexts often involves handling vague,imprecise,and uncertain information.To address this challenge,this study presents a novel multi-criteria decision-making(MCDM)approach based on picture fuzzy hypersoft sets(PFHSS),integrating the flexibility of Schweizer-Sklar triangular norm-based aggregation operators.The proposed aggregation mechanisms—weighted average and weighted geometric operators—are formulated using newly defined operational laws under the PFHSS framework and are proven to satisfy essential mathematical properties,such as idempotency,monotonicity,and boundedness.The decision-making model system-atically incorporates both benefit and cost-type criteria,enabling more nuanced evaluations in complex social or environmental decision problems.To enhance interpretability and practical relevance,the study conducts a sensitivity analysis on the Schweizer-Sklar parameter(Δ).The results show that varyingΔaffects the strictness of aggregation,thereby influencing the ranking stability of alternatives.A comparative analysis with existing fuzzy and hypersoft-based MCDM methods confirms the robustness,expressiveness,and adaptability of the proposed approach.Notably,the use of picture fuzzy sets allows for the inclusion of positive,neutral,and negative memberships,offering a richer representation of expert opinions compared to traditional models.A case study focused on green technology adoption for environmental sustainability illustrates the real-world applicability of the proposed method.The analysis confirms that the approach yields consistent and interpretable results,even under varying degrees of decision uncertainty.Overall,this work contributes an efficient and flexible MCDM tool that can support decision-makers in formulating policies aligned with sustainable and socially responsible outcomes. 展开更多
关键词 Hypersoft set picture fuzzy set Schweizer-Sklar norms aggregation operators DECISION-MAKING green technology adoption
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International Norms for Lethal Autonomous Weapon Systems:Divergences among Major Countries
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作者 Chen Genfeng Sun Xuefeng 《Contemporary International Relations》 2025年第2期19-36,共18页
Lethal autonomous weapon systems(LAWS)have become a prominent issue in global security governance.However,significant divergences remain among the world's major countries regarding their regulation:some support re... Lethal autonomous weapon systems(LAWS)have become a prominent issue in global security governance.However,significant divergences remain among the world's major countries regarding their regulation:some support restrictions,while others oppose any binding rules,and there are also countries adopting a neutral stance,though their choices are subject to external pressure.In the foreseeable future,the deployment of LAWS will increase further,raising the risk of arms races,with international support for regulating these weapons gaining strength.Yet,establishing legally binding international rules within the United Nations(UN)framework remains a distant prospect.Given this backdrop,China should continue to actively participate in international norms setting concerning LAWS under UN auspices and deepen coordination and cooperation with other countries towards more applicable norms and global governance frameworks. 展开更多
关键词 international norm international security lethal autonomous weapon system major country
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Sobolev space norm regularized full waveform inversion for ultrasound computed tomography
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作者 Panpan Li Yubing Li +2 位作者 Chang Su Zeyuan Dong Weijun Lin 《Chinese Physics B》 2025年第5期444-456,共13页
Full waveform inversion(FWI)is a complex data fitting process based on full wavefield modeling,aiming to quantitatively reconstruct unknown model parameters from partial waveform data with high-resolution.However,this... Full waveform inversion(FWI)is a complex data fitting process based on full wavefield modeling,aiming to quantitatively reconstruct unknown model parameters from partial waveform data with high-resolution.However,this process is highly nonlinear and ill-posed,therefore achieving high-resolution imaging of complex biological tissues within a limited number of iterations remains challenging.We propose a multiscale frequency–domain full waveform inversion(FDFWI)framework for ultrasound computed tomography(USCT)imaging of biological tissues,which innovatively incorporates Sobolev space norm regularization for enhancement of prior information.Specifically,we investigate the effect of different types of hyperparameter on the imaging quality,during which the regularization weight is dynamically adapted based on the ratio of the regularization term to the data fidelity term.This strategy reduces reliance on predefined hyperparameters,ensuring robust inversion performance.The inversion results from both numerical and experimental tests(i.e.,numerical breast,thigh,and ex vivo pork-belly tissue)demonstrate the effectiveness of our regularized FWI strategy.These findings will contribute to the application of the FWI technique in quantitative imaging based on USCT and make USCT possible to be another high-resolution imaging method after x-ray computed tomography and magnetic resonance imaging. 展开更多
关键词 full waveform inversion Sobolev space norm regularization ultrasound computed tomography
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APPLICATION OF THE MINIMAL NORM TENSOR PRINCIPLE IN MOBIUS GEOMETRY
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作者 XING Jin-xiong GONG Yi-fan 《数学杂志》 2025年第3期205-212,共8页
This paper addresses Pinching problems in Möbius geometry for hypersurfaces with Möbius isotropy in the unit sphere.By implementing the minimum norm tensor principle,we rigorously estimate the squared norm o... This paper addresses Pinching problems in Möbius geometry for hypersurfaces with Möbius isotropy in the unit sphere.By implementing the minimum norm tensor principle,we rigorously estimate the squared norm of the quadratic gradient term associated with the Möbius second fundamental form.This analysis yields a critical inequality governing the geometric config-uration.Leveraging this inequality,we subsequently prove a Pinching theorem characterizing the eigenvalues of the Blaschke tensor. 展开更多
关键词 minimal norm tensor Möbius second fundamental form HYPERSURFACE
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基于双注意力机制和改进L1-norm相似度的红外与可见光图像融合算法
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作者 喻康 孔祥婷 《湖北大学学报(自然科学版)》 2025年第6期822-832,共11页
针对红外与可见光图像融合方法容易造成图像特征提取不充分和易丢失中间层信息的问题,提出一种基于双注意力机制和改进L1-norm相似度的红外与可见光图像融合算法。该算法首先在编码器中引入Bottleneck残差网络,以减少模型的参数量,从而... 针对红外与可见光图像融合方法容易造成图像特征提取不充分和易丢失中间层信息的问题,提出一种基于双注意力机制和改进L1-norm相似度的红外与可见光图像融合算法。该算法首先在编码器中引入Bottleneck残差网络,以减少模型的参数量,从而高效提取出红外图像和可见光图像的深度特征图。其次,为了有效融合红外与可见光的图像特征,提出联合通道和空间的双注意力机制来提升网络捕捉重要特征信息的能力。接着,在L1-norm相似度融合策略中加入梯度提取算子对获得的深度特征图进行处理,得到对应的梯度图,并将初始融合图和对应的梯度图使用Max策略进行融合,以减少融合图像中目标信息的丢失。最后,将损失函数设置为梯度损失、像素损失和结构相似性损失的线性组合,以约束解码器重构融合图像。实验结果表明:与主流的融合算法(如DenseFuse、FusionGAN、PIAFusion、PMGI、RFN-Nest、U2Fusion等)相比,本算法在主观感受上融合效果更清晰;进一步采用标准差(SD)、互信息(MI)、视觉信息保真度(VIF)、质量指标(Qabf)、信息熵(EN)和空间频率(SF)等6个定量指标进行评估,与主流融合算法相比,前4个指标性能提升显著,较次优值分别提高了6.34%、30.48%、14.25%、4.91%,后2个指标性能接近最优的主流融合算法,融合速度约是U2Fusion的6倍。 展开更多
关键词 图像融合 红外与可见光图像 双注意力机制 L1-norm相似度 梯度转移
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1-Norm/2-Norm约束及小波多尺度2D体波走时成像 被引量:1
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作者 高级 方洪健 《物探化探计算技术》 CAS CSCD 2016年第6期765-772,共8页
在对浅地表复杂地下介质层析成像时,由于观测系统局限性及方法本身对特定岩石地球物理属性的不敏感性等因素,造成地球物理反演存在多解性。在地震走时成像中,地震射线数量在低速区域分布较少形成阴影区,造成其对低速区域成像分辨率较低... 在对浅地表复杂地下介质层析成像时,由于观测系统局限性及方法本身对特定岩石地球物理属性的不敏感性等因素,造成地球物理反演存在多解性。在地震走时成像中,地震射线数量在低速区域分布较少形成阴影区,造成其对低速区域成像分辨率较低。同时因为观测数据包含干扰信息以及不同反演方法的局限性等因素造成反演结果包含次生假异常。这里主要研究了空间域的L1-norm、L2-norm约束反演及小波域小波系数稀疏约束反演,对比不同反演方式及约束条件对地质模型的分辨能力。通过测试孤立异常模型、层状地层模型、倾斜地层模型,得出三种不同反演方式分别具有对不同特定模型的分辨特性。在实际资料成像中,可以通过使用多种反演方式,对比反演结果合理性以期达到更准确的地质构造解释。 展开更多
关键词 体波走时 层析成像 1-norm 2-norm 小波多尺度
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BIO-NORM与NORM耕地质量评价方法对比研究 被引量:22
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作者 于东升 张广星 +3 位作者 张忠启 王兴祥 史学正 杨浩 《土壤学报》 CAS CSCD 北大核心 2011年第2期238-245,共8页
耕地质量评价对指导农业生产具有极为重要的意义,耕地质量评价方法的优劣直接影响到耕地质量评价结果的可靠性。本研究以江西省余江县为研究区域,通过实际调查和样品采集与分析,获取了249个水田表层土壤属性数据和95个田块的水稻产量数... 耕地质量评价对指导农业生产具有极为重要的意义,耕地质量评价方法的优劣直接影响到耕地质量评价结果的可靠性。本研究以江西省余江县为研究区域,通过实际调查和样品采集与分析,获取了249个水田表层土壤属性数据和95个田块的水稻产量数据。利用Norm值法和新建立的Bio-Norm法,分别确定耕地质量评价指标、指标权重和隶属度函数,并对研究区水田耕地质量进行评价。两种评价方法的对比分析表明,Bio-Norm法选取的指标比Norm值法更具有代表性,得出的指标权重更能准确反映指标的重要性,确定的隶属度函数临界值更能反映水稻生长的实际要求。评价结果显示,利用Bio-Norm法得出的耕地质量综合指数(IFI值)与水稻产量回归方程的决定系数(R2)远高于Norm值法,且IFI值与水稻产量各等级的区域分布特征更为吻合。Bio-Norm法评价耕地质量更为科学合理。 展开更多
关键词 耕地质量评价 norm 水稻产量 土壤质量
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BIO-NORM与EO耕地质量评价方法对比研究 被引量:11
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作者 张广星 于东升 +2 位作者 张忠启 王兴祥 史学正 《地理科学》 CSCD 北大核心 2011年第8期1012-1018,共7页
以江西省余江县为研究区域,利用专家经验法(expert opinion,EO)和新建的Bio-Norm法,分别确定耕地质量评价指标、指标权重和隶属度函数,对研究区水田耕地质量进行评价。两种评价方法的对比分析表明,采用EO法时不同专家组选取的参评指标... 以江西省余江县为研究区域,利用专家经验法(expert opinion,EO)和新建的Bio-Norm法,分别确定耕地质量评价指标、指标权重和隶属度函数,对研究区水田耕地质量进行评价。两种评价方法的对比分析表明,采用EO法时不同专家组选取的参评指标不尽相同,评价结果具有不稳定性。Bio-Norm法得出的指标权重及确定的隶属度函数临界值,比起EO法更能反映水稻生长的实际要求;耕地质量综合指数(IFI值)与水稻产量回归方程的决定系数(R2)高于EO法,且IFI值与水稻产量各等级区域分布特征更吻合。采用Bio-Norm法评价耕地质量更为科学合理。 展开更多
关键词 耕地质量评价 专家经验法 norm 水稻产量 土壤质量
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New Constructions of Nullnorms on Bounded Lattices
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作者 Jiajia Xie Wei Ji 《Journal of Applied Mathematics and Physics》 2021年第1期1-10,共10页
We propose two more general methods to construct nullnorms on bounded lattices. By some illustrative examples, we demonstrate that the new method differ from the existing approaches.
关键词 Nullnorm Triangular norm Triangular Subnorm Bounded Lattice
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2-median location improvement problems under weighted l_1 norm and l_∞ norm on trees 被引量:1
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作者 杨利平 关秀翠 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期346-351,共6页
This paper focuses on the 2-median location improvement problem on tree networks and the problem is to modify the weights of edges at the minimum cost such that the overall sum of the weighted distance of the vertices... This paper focuses on the 2-median location improvement problem on tree networks and the problem is to modify the weights of edges at the minimum cost such that the overall sum of the weighted distance of the vertices to the respective closest one of two prescribed vertices in the modified network is upper bounded by a given value.l1 norm and l∞norm are used to measure the total modification cost. These two problems have a strong practical application background and important theoretical research value. It is shown that such problems can be transformed into a series of sum-type and bottleneck-type continuous knapsack problems respectively.Based on the property of the optimal solution two O n2 algorithms for solving the two problems are proposed where n is the number of vertices on the tree. 展开更多
关键词 2-median network improvement problem TREE knapsack problem l1 norm l∞ norm
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关于NORM开发利用设施退役源项调查方法的探讨 被引量:3
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作者 王绍林 文富平 +3 位作者 邵明刚 程友建 潘竞舜 涂兴明 《辐射防护》 CAS CSCD 北大核心 2013年第5期261-268,279,共9页
通过对以往实践经验进行总结,依照我国现行法规及技术标准,参考国际技术标准和国外良好实践,建立了一套适用于NORM开发利用设施退役源项调查的参考方法,并结合案例分析对调查方法的要点进行了探讨。这种方法的优点是,在保证调查结果可... 通过对以往实践经验进行总结,依照我国现行法规及技术标准,参考国际技术标准和国外良好实践,建立了一套适用于NORM开发利用设施退役源项调查的参考方法,并结合案例分析对调查方法的要点进行了探讨。这种方法的优点是,在保证调查结果可靠的前提下,将大量的实验室分析工作代之以现场监测,从而减轻了实验室的工作负担。希望对今后同类工作的开展提供参考。 展开更多
关键词 norm开发利用设施 源项调查 退役治理
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磷矿采选及磷酸盐相关产品生产的NORM问题 被引量:3
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作者 吴其反 马成辉 +3 位作者 罗建军 杨名生 喻亦林 彭崇 《辐射防护》 CAS CSCD 北大核心 2011年第6期353-363,共11页
2007年的统计结果表明:产生废物量最大的主要行业是钢铁和煤炭行业,分别占总废物总量的43.6%和28.8%,其次是铜和磷酸盐行业,分别占6.3%和4.62%,其余各行业产生的废物量都小于3%;其中钢铁、煤炭、铜和磷酸盐行业原矿外照射剂量率平均值... 2007年的统计结果表明:产生废物量最大的主要行业是钢铁和煤炭行业,分别占总废物总量的43.6%和28.8%,其次是铜和磷酸盐行业,分别占6.3%和4.62%,其余各行业产生的废物量都小于3%;其中钢铁、煤炭、铜和磷酸盐行业原矿外照射剂量率平均值分别是162 nGy/h、153 nGy/h、170 nGy/h和273 nGy/h,磷酸盐行业外照射水平较高。我国以往的相关工作基本查明磷矿分布区域,磷矿采选和磷酸盐相关产品生产企业,天然放射性水平较高矿石、废渣和部分产品238U、226Ra和40K核素活度浓度,但是,对开采含天然放射性核素较高的磷矿石,或使用这些磷矿石进行生产的企业开展辐射影响评价,以及这些企业在生产过程中对周围环境影响的评价非常有限,监测技术方法也需要进一步完善。在第一次全国污染源普查基础上,选择有代表性的磷酸盐生产企业进行辐射监测与环境影响评价研究具有重要的意义。 展开更多
关键词 磷酸盐 磷矿采选 norm 辐射环境影响
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L1 norm optimal solution match processing in the wavelet domain 被引量:1
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作者 龙云 韩立国 +1 位作者 韩利 谭尘青 《Applied Geophysics》 SCIE CSCD 2012年第4期451-458,496,共9页
Greater attention has been paid to vintage-merge processing of seismic data and extracting more valuable information by the geophysicist. A match filter is used within many important areas such as splicing seismic dat... Greater attention has been paid to vintage-merge processing of seismic data and extracting more valuable information by the geophysicist. A match filter is used within many important areas such as splicing seismic data, matching seismic data with different ages and sources, 4-D seismic monitoring, and so on. The traditional match filtering method is subject to many restrictions and is usually difficult to overcome the impact of noise. Based on the traditional match filter, we propose the wavelet domain L1 norm optimal matching filter. In this paper, two different types of seismic data are decomposed to the wavelet domain, different detailed effective information is extracted for Ll-norm optimal matching, and ideal results are achieved. Based on the model test, we find that the L1 norm optimal matching filter attenuates the noise and the waveform, amplitude, and phase coherence of result signals are better than the conventional method. The field data test shows that, with our method, the seismic events in the filter results have better continuity which achieves the high precision seismic match requirements. 展开更多
关键词 Wavelet transform matching filter L 1 norm waveform consistency
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关于translation norms汉译的探索 被引量:3
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作者 喻旭东 《上海翻译》 CSSCI 北大核心 2018年第6期30-34,共5页
[摘要]Translation Norms理论在本世纪初被引入中国,对我国的翻译研究、翻译实践以及翻译教学具有重大意义。然而至今,translation norms概念在国内翻译领域中未能普及,学者对其范畴存在误解。译名统一是该理论在我国旅行的前提,基于对t... [摘要]Translation Norms理论在本世纪初被引入中国,对我国的翻译研究、翻译实践以及翻译教学具有重大意义。然而至今,translation norms概念在国内翻译领域中未能普及,学者对其范畴存在误解。译名统一是该理论在我国旅行的前提,基于对translation norms内涵的分析以及对"norms"和"规范"两词的解读,建议将其汉译为"翻译规范"。 展开更多
关键词 TRANSLATION norms翻译 规范 翻译规范 译名统一
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基于TV-norm的阈值迭代分割算法 被引量:1
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作者 高冉 赵辉 +1 位作者 职占江 宋锦萍 《河南大学学报(自然科学版)》 CAS 北大核心 2009年第3期225-230,共6页
提出了一种基于TV-norm的阈值迭代分割算法.该算法首先用局部阈值迭代法确定各个子图像的阈值,得到一个待处理的矩阵;然后利用TV-norm对阈值矩阵进行插值处理,使之成为与原图像像素数目相同的新矩阵,得到光滑的阈值曲面,进而实现对图像... 提出了一种基于TV-norm的阈值迭代分割算法.该算法首先用局部阈值迭代法确定各个子图像的阈值,得到一个待处理的矩阵;然后利用TV-norm对阈值矩阵进行插值处理,使之成为与原图像像素数目相同的新矩阵,得到光滑的阈值曲面,进而实现对图像的分割;最后通过仿真试验说明该算法的可行性和有效性. 展开更多
关键词 图像分割 局部阈值迭代 TV-norm 阈值曲面
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NORM/TENORM照射的管理 被引量:12
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作者 罗建军 孙庆红 《辐射防护通讯》 2009年第3期4-12,共9页
阐述了国际原子能机构、欧盟等国际组织和部分国家NORM/TENORM照射的管理方式,讨论了需关注的问题,针对我国的NORM/TENORM照射管理现状提出了相应建议。
关键词 norm/TEnorm 照射 审管方式
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