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ISO25000-Related Metrics for Evaluating the Quality of Complex Information Systems
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作者 Antonia Stefani Bill Vassiliadis 《Journal of Computer and Communications》 2023年第9期18-43,共26页
Evaluating complex information systems necessitates deep contextual knowledge of technology, user needs, and quality. The quality evaluation challenges increase with the system’s complexity, especially when multiple ... Evaluating complex information systems necessitates deep contextual knowledge of technology, user needs, and quality. The quality evaluation challenges increase with the system’s complexity, especially when multiple services supported by varied technological modules, are offered. Existing standards for software quality, such as the ISO25000 series, provide a broad framework for evaluation. Broadness offers initial implementation ease albeit, it often lacks specificity to cater to individual system modules. This paper maps 48 data metrics and 175 software metrics on specific system modules while aligning them with ISO standard quality traits. Using the ISO25000 series as a foundation, especially ISO25010 and 25012, this research seeks to augment the applicability of these standards to multi-faceted systems, exemplified by five distinct software modules prevalent in modern information ecosystems. 展开更多
关键词 Software Quality information Systems Quality Standards Quality metrics ISO25000
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EKELAND’S VARIATIONAL PRINCIPLE AND CARISTI’S COINCIDENCE THEOREM FOR SET-VALUED MAPPINGS IN PROBABILISTIC METRIC SPACES
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作者 张石生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第7期607-614,共8页
By using the partial ordering method,a more general type,of Ekeland’s ariational principle and a set-valued Caristi’s coincidence theorem in probabilistic metric spaces are obtained.In addition,a direct simple proof... By using the partial ordering method,a more general type,of Ekeland’s ariational principle and a set-valued Caristi’s coincidence theorem in probabilistic metric spaces are obtained.In addition,a direct simple proof of the equivalence between these two theorems in probabilistic metric spaces is given. 展开更多
关键词 probabilistic metric space Caristi's coincidence theorem Ekeland's variational principle partial ordering set.
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A Variational Principle in Probabilistic Metric Spaces(Ⅱ)~* 概率度量空间中的变分原理
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作者 何培均 《贵州大学学报(自然科学版)》 1994年第1期8-12,共5页
本文研究概率度量空间中的变分原理.我们证明了概率分析中的一个序原理,应用这个序原理并引入分布值映射的下半连续性概念,把Ekeland变分原理和Caristi不动点定理推广到概率度量空间中.
关键词 概率度量空间 变分原理 不动点
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Some Approximation in Cone Metric Space and Variational Iterative Method
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作者 Ning Chen Jiqian Chen 《Applied Mathematics》 2012年第12期2007-2018,共12页
In this paper, we give some new results of common fixed point theorems and coincidence point case for some iterative method. By using of variation iteration method and an effective modification of He’s variation iter... In this paper, we give some new results of common fixed point theorems and coincidence point case for some iterative method. By using of variation iteration method and an effective modification of He’s variation iteration method discusses some integral and differential equations, we give out some new conclusion and more new examples. 展开更多
关键词 CONE metric Space Common Fixed Point Effective variation ITERATION Method Integral-Differential Equation
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基于SVMD-Informer-XGBoost的风电功率区间预测
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作者 黄丹 张历卓 +1 位作者 陈思羽 匡迎春 《长江信息通信》 2024年第10期34-37,共4页
为了提高风电功率区间预测的精度,文章提出逐次变分模态分解(SVMD)、Informer和XGBoost算法模型的结合,实现风电功率区间预测。首先,SVMD算法自适应地分解出风电功率数据的各模态分量(IMF)和残差分量。其次,通过网格搜索算法(CV)对Infor... 为了提高风电功率区间预测的精度,文章提出逐次变分模态分解(SVMD)、Informer和XGBoost算法模型的结合,实现风电功率区间预测。首先,SVMD算法自适应地分解出风电功率数据的各模态分量(IMF)和残差分量。其次,通过网格搜索算法(CV)对Informer和XGBoost模型算法进行优化,并通过网格搜索算法确定Informer-XGBoost输出预测值的最优权重,构建基于SVMD-Informer-XGBoost的预测模型。最后,通过分位数回归法(Quantile regression)输出预测值和真实值的误差,得到风电功率的区间预测。实验结果表明,所提出的方法相较于传统单一模型,在区间预测的准确度和稳定性上有了显著提升。在95%置信度水平下,区间预测指标区间覆盖率(PICP)和区间平均宽度(PINAW)分别可达94.96%和0.0362。 展开更多
关键词 逐次变分模态分解 XGBoost informER 网格搜索
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A New Fixed Point Theorem in FC-Metric Spaces with Applications to Variational Inequalities and Saddle Points 被引量:1
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《大学数学》 2013年第5期23-27,共5页
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基于STAGCN-Informer时空组合模型的风电功率预测方法
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作者 杨绍祖 王海程 +1 位作者 吴金雅 马纪颖 《计算机与现代化》 2024年第7期13-20,共8页
针对风电功率预测中,空间信息受时空波动性和随机性影响无法有效提取,导致预测精度不足的问题,提出一种基于变分模态分解(Variational Mode Decomposition,VMD)、融合时空注意力图卷积网络(Spatiotemporal Attention Graph Convolutiona... 针对风电功率预测中,空间信息受时空波动性和随机性影响无法有效提取,导致预测精度不足的问题,提出一种基于变分模态分解(Variational Mode Decomposition,VMD)、融合时空注意力图卷积网络(Spatiotemporal Attention Graph Convolutional Network,STAGCN)和改进Informer的组合模型(STAGCN-Informer-DCP)。首先运用VMD对原始特征进行模态分解,提取出不同时间尺度上的特征信息。同时利用北方苍鹰算法(Northern Goshawk Optimization,NGO)优化VMD的核心参数(惩罚因子和K值)选择。其次,利用融合时空注意力的STAGCN模块动态捕捉目标风机与近邻相似风机的时空特征,并将其与原始的信号分量融合获得携带空间尺度信息的特征向量。最后使用改进的Informer模型提取时序上下文的长期依赖关系,并实现多步输出预测。实验结果表明,该组合模型能较好地捕捉动态时空依赖,并有效提高了中长期风电预测的准确度。 展开更多
关键词 变分模态分解 时空注意力机制 informer模型 北方苍鹰优化算法 图卷积网络
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Algorithms of common solutions to quasi variational inclusion and fixed point problems 被引量:2
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作者 张石生 李向荣 陈志坚 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第5期571-581,共11页
The purpose of this paper is to present an iterative scheme for finding a common element of the set of solutions to the variational inclusion problem with multivalued maximal monotone mapping and inverse-strongly mono... The purpose of this paper is to present an iterative scheme for finding a common element of the set of solutions to the variational inclusion problem with multivalued maximal monotone mapping and inverse-strongly monotone mappings and the set of fixed points of nonexpansive mappings in Hilbert space.Under suitable conditions, some strong convergence theorems for approximating this common elements are proved. The results presented in the paper not only improve and extend the main results in Korpelevich(Ekonomika i Matematicheskie Metody,1976,12(4):747-756),but also extend and replenish the corresponding results obtained by Iiduka and Takahashi(Nonlinear Anal TMA,2005,61(3):341-350),Takahashi and Toyoda(J Optim Theory Appl,2003, 118(2):417-428),Nadezhkina and Takahashi(J Optim Theory Appl,2006,128(1):191- 201),and Zeng and Yao(Taiwan Residents Journal of Mathematics,2006,10(5):1293-1303). 展开更多
关键词 variational inclusion multi-valued maximal monotone mapping inversestrongly monotone mapping metric projection fixed point nonexpansive mapping
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An analysis on spatial variation of urban human thermal comfort in Hangzhou, China 被引量:3
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作者 WANGWei-wu ZHULi-zhong WANGRen-chao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第2期332-338,共7页
Urban human thermal comfort(UHTC) is affected for interacting of weather condition and underlying surface framework of urban area. Urban underlying surface temperature value and Normalized Difference Vegetation Index(... Urban human thermal comfort(UHTC) is affected for interacting of weather condition and underlying surface framework of urban area. Urban underlying surface temperature value and Normalized Difference Vegetation Index(NDVI) were calculated using image interpreting and supervised classification technique by ERDAS IMAGE software using 1991 and 1999 Landsat TM images data. Reference to the relational standard of assessing human thermal comfort and other meteorology data of Hangzhou City in summer, air temperature and relative humidity variation of different land types of underlying surface were inversed. By choosing discomfort index as an indictor, the spatial distribution characteristic and the spatial variation degree of UHTC were estimated and mapped on a middle scale, that is, in six districts of Hangzhou. The main characteristics of UHTC spatial variation from 1991 to 1999 were revealed using a GIS-based calculation model. The variation mechanism were analyzed and discussed from the viewpoint of city planning, construction and environmental protection. 展开更多
关键词 urban human thermal comfort(UHTC) remote sen sing(RS) geographic information system(GIS) spatial distribution variation me chanism
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基于VMD-Informer-BiLSTM模型的超短期光伏功率预测 被引量:21
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作者 滕陈源 丁逸超 +2 位作者 张有兵 李烁 莫雅俊 《高电压技术》 EI CAS CSCD 北大核心 2023年第7期2961-2971,共11页
由于光伏出力的波动性和随机性给电网的规划和运行带来了挑战,因此提高光伏功率预测的精度对提升新能源系统的稳定性具有重要意义。为此提出了一种结合模态分解、多维特征建模、Informer、双向长短期神经网络(bidirectional long short-... 由于光伏出力的波动性和随机性给电网的规划和运行带来了挑战,因此提高光伏功率预测的精度对提升新能源系统的稳定性具有重要意义。为此提出了一种结合模态分解、多维特征建模、Informer、双向长短期神经网络(bidirectional long short-term memory network,BiLSTM)的超短期光伏组合预测模型。首先通过变分模态分解将光伏功率序列分解成不同频率的本征模态函数(intrinsic mode function,IMF),降低光伏功率信号的非平稳性与复杂度;随后使用离散小波变换提取天气因素中的细节分量,实现不同分解算法的优势互补,并用随机森林算法为每个IMF筛选冗余特征,然后将特征矩阵送入Informer进行建模,提取不同时间步中关键时刻的信息,提高对长时间序列的预测效率;最后为进一步提高模型预测精度,分析误差序列特性,利用BiLSTM进行误差校正。采用实际光伏数据进行算例分析,结果表明所提方法提高了超短期光伏功率预测精度。 展开更多
关键词 光伏功率预测 时间序列 变分模态分解 informER 双向长短期神经网络 集成预测
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Spatial and Temporal Variation of Urban Air Quality: A GIS Approach 被引量:3
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作者 Subrata Chattopadhyay Srimanta Gupta Raj Narayan Saha 《Journal of Environmental Protection》 2010年第3期264-277,共14页
This study investigated the seasonal variation of ambient air quality status of Burdwan town using GIS approach. Concentration of SOR2R (sulphur dioxide), NOR2R (nitrogen dioxide) and RSPM (respiratory suspended parti... This study investigated the seasonal variation of ambient air quality status of Burdwan town using GIS approach. Concentration of SOR2R (sulphur dioxide), NOR2R (nitrogen dioxide) and RSPM (respiratory suspended particulate matter) were measured once a week for 24 hour in both premonsoon and postmonsoon season. The seasonal average concentration of the RSPM, SOR2R and NOR2R in premonsoon season was observed to be 188.56 ± 88.63, 5.12 ± 6.27 and 92.51 ± 64.78 mg/mP3P respectively whereas in postmonsoon it was 53.03 ± 38.27, 8.51 ± 7.11 and 162.85 ± 184.80 mg/mP3P respectively. Statistical analysis showed the significant monsoonal effect on mean difference of RSPM, SOR2R and NOR2R concentration. Postmonsoon concentration of ambient SOR2R and NOR2R were observed to be higher than premonsoon, suggesting longer residence times of these pollutants in the atmosphere due to stagnant conditions and low mixing height. Spatial distribution of pollutants throughout the town in both the season was represented by digital elevation model (DEM). On the basis of Air Quality Index (AQI) a GIS based air pollution surface models were generated in both the seasons by means of Inverse Distance Interpolation (IDINT) technique. From the output surface model it was found that in comparison to premonsoon there was a significant increase of clean and fairly clean area and decrease of moderately polluted area of the town during postmonsoon. 展开更多
关键词 AMBIENT AIR QUALITY SEASONAL variatION AIR QUALITY Index (AQI) GEOGRAPHIC information System (GIS)
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Online RGB-D person re-identification based on metric model update 被引量:5
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作者 Hong Liu Liang Hu Liclian Ma 《CAAI Transactions on Intelligence Technology》 2017年第1期48-55,共8页
Person re-identification (re-id) on robot platform is an important application for human-robot- interaction (HRI), which aims at making the robot recognize the around persons in varying scenes. Although many effec... Person re-identification (re-id) on robot platform is an important application for human-robot- interaction (HRI), which aims at making the robot recognize the around persons in varying scenes. Although many effective methods have been proposed for surveillance re-id in recent years, re-id on robot platform is still a novel unsolved problem. Most existing methods adapt the supervised metric learning offline to improve the accuracy. However, these methods can not adapt to unknown scenes. To solve this problem, an online re-id framework is proposed. Considering that robotics can afford to use high-resolution RGB-D sensors and clear human face may be captured, face information is used to update the metric model. Firstly, the metric model is pre-trained offline using labeled data. Then during the online stage, we use face information to mine incorrect body matching pairs which are collected to update the metric model online. In addition, to make full use of both appearance and skeleton information provided by RGB-D sensors, a novel feature funnel model (FFM) is proposed. Comparison studies show our approach is more effective and adaptable to varying environments. 展开更多
关键词 Person re-identification Online metric model update Face information Skeleton information
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Metric of States
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作者 MA Zhi-Hao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第11期1069-1070,共2页
Metric of quantum states plays an important role in quantum information theory. In this letter, we find the deep connection between quantum logic theory and quantum information theory. Using the method of quantum logi... Metric of quantum states plays an important role in quantum information theory. In this letter, we find the deep connection between quantum logic theory and quantum information theory. Using the method of quantum logic, we can get a famous inequality in quantum information theory, and we answer a question raised by S. Gudder. 展开更多
关键词 STATE density operator metric FIDELITY quantum information quantum logic
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On Generalized Multivalued Random Variational-Like Inclusions
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作者 Mohammad Kalimuddin Ahmad Salahuddin . 《Applied Mathematics》 2011年第8期1011-1018,共8页
In this paper, we posed a random iterative algorithm for generalized multivalued random variational like inclusions. We define the random relaxed Lipschitz and relaxed monotone mappings and prove the existence and con... In this paper, we posed a random iterative algorithm for generalized multivalued random variational like inclusions. We define the random relaxed Lipschitz and relaxed monotone mappings and prove the existence and convergence of solutions of the random iterative sequences generated by a random iterative algorithm. 展开更多
关键词 Generalized Multivalued RANDOM variational Like INCLUSIONS RANDOM Iterative Sequences Measurable SPACE SEPARABLE Real HILBERT SPACE η-Subdifferential HAUSDORFF metric
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Single Nucleotide Polymorphisms: A Window into the Informatics of the Living Genome
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作者 Georgia M. Dunston Tshela E. Mason +1 位作者 William Hercules James Lindesay 《Advances in Bioscience and Biotechnology》 2014年第7期623-626,共4页
Nested in the environment of the nucleus of the cell, the 23 sets of chromosomes that comprise the human genome function as one integrated whole system, orchestrating the expression of thousands of genes underlying th... Nested in the environment of the nucleus of the cell, the 23 sets of chromosomes that comprise the human genome function as one integrated whole system, orchestrating the expression of thousands of genes underlying the biological characteristics of the cell, individual and the species. The extraction of meaningful information from this complex data set depends crucially upon the lens through which the data are examined. We present a biophysical perspective on genomic information encoded in single nucleotide polymorphisms (SNPs), and introduce metrics for modeling information encoded in the genome. Information, like energy, is considered to be a conserved physical property of the universe. The information structured in SNPs describes the adaptation of a human population to a given environment. The maintained order measured by the information content is associated with entropies, energies, and other state variables for a dynamic system in homeostasis. “Genodynamics” characterizes the state variables for genomic populations that are stable under stochastic environmental stresses. The determination of allelic energies allows the parameterization of specific environmental influences upon individual alleles across populations. The environment drives population-based genome variation. From this vantage point, the genome is modeled as a complex, dynamic information system defined by patterns of SNP alleles and SNP haplotypes. 展开更多
关键词 SNPS GENOMIC information Genodynamics BIOPHYSICAL metrics Allelic ENERGIES
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Genetic Variation of Inbred Lines of Maize Detected by SSR Markers
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作者 LI Xin-hai FU Jun-hua ZHANG Shi-huang YUAN Li-xing LI Ming-shun 《Agricultural Sciences in China》 CAS CSCD 2001年第1期14-20,共7页
Simple sequence repeats (SSRs) were used to detect genetic variation among 21 maize(Zea mays L. ) inbred lines. Forty-three SSR primers selected from 69 primers gave stable amplification profiles, which could be clear... Simple sequence repeats (SSRs) were used to detect genetic variation among 21 maize(Zea mays L. ) inbred lines. Forty-three SSR primers selected from 69 primers gave stable amplification profiles, which could be clearly resolved on 3% Metaphor agarose gel, and produced 127 polymorphic amplified fragments.The average number of alleles per SSR locus was 2.95 with a range from 2 to 7. The polymorphism information content (PIC) for the SSR loci varied from 0.172 to 0.753 with an average of 0.511. Genetic similarities among the 21 lines ranged from 0.480 between the combination of Zhongzi451 vs. K12 up to 0.768 between CA156 vs. Ye478. The cluster analysis showed that 21 inbred lines could be classified into two distinct clusters with several subclusters, which corresponded to the heterotic groups determined by their pedigree information.Eight SSR primers, which had high level of polymorphism, could allow a rapid and efficient identification of 21 inbreds. Consequently, SSR markers could be used for measuring genetic variation of maize inbred lines and assigning them to heterotic groups. 展开更多
关键词 MAIZE Simple sequence REPEATS Genetic variation Heterotic groups POLYMORPHISM information content
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A Modified Newton Method Based on the Metric Projector for Solving SOCCVI Problem
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作者 Hao Liu Juhe Sun Li Wang 《Journal of Applied Mathematics and Physics》 2022年第4期1036-1054,共19页
In this paper, based on the second-order sufficient condition, the Clarke's generalized Jacobian of the Karush-Kuhn-Tucker system of the second-order cone constrained variational inequality (SOCCVI) problem that i... In this paper, based on the second-order sufficient condition, the Clarke's generalized Jacobian of the Karush-Kuhn-Tucker system of the second-order cone constrained variational inequality (SOCCVI) problem that is nonsingular is proved by us. A modified Newton method with Armijo line search is presented. Three illustrative examples are given to show how the modified Newton method works. 展开更多
关键词 Second-Order Cone variational Inequality metric Projector Second-Order Sufficient Condition
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Remote Sensing and Landscape Metrics-Based Forest Physical Degradation: Two-Decades Assessment in Gishwati-Mukura Biological Corridor in Rwanda, East-Central Africa
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作者 Hassina Uwiringiyimana Jaeyong Choi 《Journal of Geoscience and Environment Protection》 2022年第4期64-81,共18页
The management of forest corridors and related ecology is one of the effective strategies to minimize the adverse effects of forest degradation. It controls the connectivity of inhabitant species and the connection of... The management of forest corridors and related ecology is one of the effective strategies to minimize the adverse effects of forest degradation. It controls the connectivity of inhabitant species and the connection of the isolated patches. This study analyzed spatial and temporal forest physical degradation based on forest cover change and forest fragmentation in the Gishwati-Mukura biological corridor from 1990-2019. Remotely sensed datasets, Geographical Information System (GIS) and FRAGSTATS software were used to analyze the spatial and temporal physical degradation and changes in forest cover. The results indicated that the Gishwati-Mukura corridor experienced massive deforestation where approximately 7617.1 ha (64.22%) of forest cover was completely cleared out, which implies an annual forest loss of 262.6 ha&#183;year<sup>-</sup><sup>1</sup> (2.21%) during 1990-2019. The forest cover transitions patterns and geostatistical analysis indicated that extensive deforestation was associated with intensive agriculture. The results demonstrated that agriculture has dramatically increased from 29.46% in 1990 to 57.22% in 2019, with an annual increase of 1.97%. Since Gishwati-Mukura has changed to National Park (NP), it lacks diversified scientific studies addressing the analysis of the remote and spatial patterns to investigate its physical degradation and landscape dynamics. This research study will serve as remote forest analysis gap-filling and as the cornerstone of numerous other research that will contribute to the improvement of the connectivity assessments along the Gishwati-Mukura corridor and other related ecosystems. 展开更多
关键词 Landscape metrics Remote Sensing Geographic information System (GIS) Forest Physical Degradation Biological Corridor National Park
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EXISTENCE AND ITERATIVE ALGORITHMS OF SOLUTIONS FOR GENERALIZED MIXED QUASI_VARIATIONAL INEQUALITIES
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作者 罗春林 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第9期1038-1045,共8页
In this paper, by using the auxiliary technique of variational inequalities, the existence and iterative algorithm; of solutions for a class of generalized mixed quasi-variational inequalities are studied. Our results... In this paper, by using the auxiliary technique of variational inequalities, the existence and iterative algorithm; of solutions for a class of generalized mixed quasi-variational inequalities are studied. Our results answer the open problems mentioned by Noor, improve and generalize some recent known results. 展开更多
关键词 generalized mixed quasi-variational inequalities strongly monotone Lipschitz continuous Hausdorff metric
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特征与度量联合优化信息几何检测器
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作者 吴昊 程永强 +2 位作者 杨政 王宏强 黎湘 《电子学报》 EI CAS CSCD 北大核心 2024年第6期1977-1988,共12页
目前,信息几何检测器主要采用协方差矩阵特征模型,在矩阵流形上度量待检测单元数据与杂波数据间的差异,以区分目标与杂波,从而实现雷达目标检测.然而,在复杂杂波背景下,雷达回波信号信杂比低,杂波在其中占据主导地位.因此,含有目标回波... 目前,信息几何检测器主要采用协方差矩阵特征模型,在矩阵流形上度量待检测单元数据与杂波数据间的差异,以区分目标与杂波,从而实现雷达目标检测.然而,在复杂杂波背景下,雷达回波信号信杂比低,杂波在其中占据主导地位.因此,含有目标回波的雷达回波信号与纯杂波具有统计相似性,该相似性使得二者在矩阵流形上较难区分,从而限制了信息几何检测器的性能优势.为突破特征表示所造成的性能增益限制,本文提出了基于特征与度量联合优化的信息几何检测器.首先设计了特征与度量可调的信息几何检测器灵活框架,并在此基础上基于纽曼-皮尔逊准则建立了特征与度量的联合优化模型,而后利用局部平坦假设与多层感知器,将联合优化模型中的决策变量参数化,并提出了双阶段优化求解方法.基于仿真数据与实测海杂波数据的实验结果表明,该方法检测性能优于现有信息几何检测器等典型目标检测方法,且在目标多普勒接近杂波谱峰时具有较大优势. 展开更多
关键词 雷达目标检测 信息几何检测器 特征流形 联合优化 特征优化 度量优化
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