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Bernoulli-based random undersampling schemes for 2D seismic data regularization 被引量:4
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作者 蔡瑞 赵群 +3 位作者 佘德平 杨丽 曹辉 杨勤勇 《Applied Geophysics》 SCIE CSCD 2014年第3期321-330,351,352,共12页
Seismic data regularization is an important preprocessing step in seismic signal processing. Traditional seismic acquisition methods follow the Shannon–Nyquist sampling theorem, whereas compressive sensing(CS) prov... Seismic data regularization is an important preprocessing step in seismic signal processing. Traditional seismic acquisition methods follow the Shannon–Nyquist sampling theorem, whereas compressive sensing(CS) provides a fundamentally new paradigm to overcome limitations in data acquisition. Besides the sparse representation of seismic signal in some transform domain and the 1-norm reconstruction algorithm, the seismic data regularization quality of CS-based techniques strongly depends on random undersampling schemes. For 2D seismic data, discrete uniform-based methods have been investigated, where some seismic traces are randomly sampled with an equal probability. However, in theory and practice, some seismic traces with different probability are required to be sampled for satisfying the assumptions in CS. Therefore, designing new undersampling schemes is imperative. We propose a Bernoulli-based random undersampling scheme and its jittered version to determine the regular traces that are randomly sampled with different probability, while both schemes comply with the Bernoulli process distribution. We performed experiments using the Fourier and curvelet transforms and the spectral projected gradient reconstruction algorithm for 1-norm(SPGL1), and ten different random seeds. According to the signal-to-noise ratio(SNR) between the original and reconstructed seismic data, the detailed experimental results from 2D numerical and physical simulation data show that the proposed novel schemes perform overall better than the discrete uniform schemes. 展开更多
关键词 Seismic data regularization compressive sensing Bernoulli distribution sparse transform UNDERSAMPLING 1-norm reconstruction algorithm.
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Diverse Deep Matrix Factorization With Hypergraph Regularization for Multi-View Data Representation
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作者 Haonan Huang Guoxu Zhou +2 位作者 Naiyao Liang Qibin Zhao Shengli Xie 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第11期2154-2167,共14页
Deep matrix factorization(DMF)has been demonstrated to be a powerful tool to take in the complex hierarchical information of multi-view data(MDR).However,existing multiview DMF methods mainly explore the consistency o... Deep matrix factorization(DMF)has been demonstrated to be a powerful tool to take in the complex hierarchical information of multi-view data(MDR).However,existing multiview DMF methods mainly explore the consistency of multi-view data,while neglecting the diversity among different views as well as the high-order relationships of data,resulting in the loss of valuable complementary information.In this paper,we design a hypergraph regularized diverse deep matrix factorization(HDDMF)model for multi-view data representation,to jointly utilize multi-view diversity and a high-order manifold in a multilayer factorization framework.A novel diversity enhancement term is designed to exploit the structural complementarity between different views of data.Hypergraph regularization is utilized to preserve the high-order geometry structure of data in each view.An efficient iterative optimization algorithm is developed to solve the proposed model with theoretical convergence analysis.Experimental results on five real-world data sets demonstrate that the proposed method significantly outperforms stateof-the-art multi-view learning approaches. 展开更多
关键词 Deep matrix factorization(DMF) diversity hypergraph regularization multi-view data representation(MDR)
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Iteratively Weighted Least Square Inversion of 3D Seismic Data Regularization under Constraints of Local Plane Wave Model
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作者 Liu Yujin Li Zhenchun 《石油地球物理勘探》 EI CSCD 北大核心 2012年第A02期41-47,共7页
关键词 石油 地球物理勘探 地质调查 油气资源
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Data-Path Placement Based on Regularity Extraction and Implementation
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作者 杨长旗 洪先龙 +2 位作者 蔡懿慈 经彤 吴为民 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第8期925-936,共12页
An algorithm named DPP is addressed.In it,a new model based on the concept of irregularity degree is founded to evaluate the regularity of cells.It generates the structure regularity of cells by exploiting the signal ... An algorithm named DPP is addressed.In it,a new model based on the concept of irregularity degree is founded to evaluate the regularity of cells.It generates the structure regularity of cells by exploiting the signal flow of circuit.Then,it converts the bit slice structure to parallel constraints to enable Q place algorithm.The design flow and the main algorithms are introduced.Finally,the satisfied experimental result of the tool compared with the Cadence placement tool SE is discussed. 展开更多
关键词 data Path regularity extraction bit slice structure Q place
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Regularized least-squares migration of simultaneous-source seismic data with adaptive singular spectrum analysis 被引量:12
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作者 Chuang Li Jian-Ping Huang +1 位作者 Zhen-Chun Li Rong-Rong Wang 《Petroleum Science》 SCIE CAS CSCD 2017年第1期61-74,共14页
Simultaneous-source acquisition has been recog- nized as an economic and efficient acquisition method, but the direct imaging of the simultaneous-source data produces migration artifacts because of the interference of... Simultaneous-source acquisition has been recog- nized as an economic and efficient acquisition method, but the direct imaging of the simultaneous-source data produces migration artifacts because of the interference of adjacent sources. To overcome this problem, we propose the regularized least-squares reverse time migration method (RLSRTM) using the singular spectrum analysis technique that imposes sparseness constraints on the inverted model. Additionally, the difference spectrum theory of singular values is presented so that RLSRTM can be implemented adaptively to eliminate the migration artifacts. With numerical tests on a fiat layer model and a Marmousi model, we validate the superior imaging quality, efficiency and convergence of RLSRTM compared with LSRTM when dealing with simultaneoussource data, incomplete data and noisy data. 展开更多
关键词 Least-squares migration Adaptive singularspectrum analysis regularization Blended data
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Graph Regularized L_p Smooth Non-negative Matrix Factorization for Data Representation 被引量:10
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作者 Chengcai Leng Hai Zhang +2 位作者 Guorong Cai Irene Cheng Anup Basu 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2019年第2期584-595,共12页
This paper proposes a Graph regularized Lpsmooth non-negative matrix factorization(GSNMF) method by incorporating graph regularization and L_p smoothing constraint, which considers the intrinsic geometric information ... This paper proposes a Graph regularized Lpsmooth non-negative matrix factorization(GSNMF) method by incorporating graph regularization and L_p smoothing constraint, which considers the intrinsic geometric information of a data set and produces smooth and stable solutions. The main contributions are as follows: first, graph regularization is added into NMF to discover the hidden semantics and simultaneously respect the intrinsic geometric structure information of a data set. Second,the Lpsmoothing constraint is incorporated into NMF to combine the merits of isotropic(L_2-norm) and anisotropic(L_1-norm)diffusion smoothing, and produces a smooth and more accurate solution to the optimization problem. Finally, the update rules and proof of convergence of GSNMF are given. Experiments on several data sets show that the proposed method outperforms related state-of-the-art methods. 展开更多
关键词 data clustering dimensionality reduction GRAPH regularization LP SMOOTH non-negative matrix factorization(SNMF)
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An enrichment model using regular health examination data for early detection of colorectal cancer 被引量:3
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作者 Qiang Shi Zhaoya Gao +8 位作者 Pengze Wu Fanxiu Heng Fuming Lei Yanzhao Wang Qingkun Gao Qingmin Zeng Pengfei Niu Cheng Li Jin Gu 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2019年第4期686-698,共13页
Objective: Challenges remain in current practices of colorectal cancer(CRC) screening, such as low compliance,low specificities and expensive cost. This study aimed to identify high-risk groups for CRC from the genera... Objective: Challenges remain in current practices of colorectal cancer(CRC) screening, such as low compliance,low specificities and expensive cost. This study aimed to identify high-risk groups for CRC from the general population using regular health examination data.Methods: The study population consist of more than 7,000 CRC cases and more than 140,000 controls. Using regular health examination data, a model detecting CRC cases was derived by the classification and regression trees(CART) algorithm. Receiver operating characteristic(ROC) curve was applied to evaluate the performance of models. The robustness and generalization of the CART model were validated by independent datasets. In addition, the effectiveness of CART-based screening was compared with stool-based screening.Results: After data quality control, 4,647 CRC cases and 133,898 controls free of colorectal neoplasms were used for downstream analysis. The final CART model based on four biomarkers(age, albumin, hematocrit and percent lymphocytes) was constructed. In the test set, the area under ROC curve(AUC) of the CART model was 0.88 [95%confidence interval(95% CI), 0.87-0.90] for detecting CRC. At the cutoff yielding 99.0% specificity, this model’s sensitivity was 62.2%(95% CI, 58.1%-66.2%), thereby achieving a 63-fold enrichment of CRC cases. We validated the robustness of the method across subsets of test set with diverse CRC incidences, aging rates, genders ratio, distributions of tumor stages and locations, and data sources. Importantly, CART-based screening had the higher positive predictive value(1.6%) than fecal immunochemical test(0.3%).Conclusions: As an alternative approach for the early detection of CRC, this study provides a low-cost method using regular health examination data to identify high-risk individuals for CRC for further examinations. The approach can promote early detection of CRC especially in developing countries such as China, where annual health examination is popular but regular CRC-specific screening is rare. 展开更多
关键词 Classification and regression trees COLORECTAL cancer regular health examination data ROUTINE lab test biomarkers
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Data Gathering in Wireless Sensor Networks Via Regular Low Density Parity Check Matrix 被引量:1
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作者 Xiaoxia Song Yong Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第1期83-91,共9页
A great challenge faced by wireless sensor networks(WSNs) is to reduce energy consumption of sensor nodes. Fortunately, the data gathering via random sensing can save energy of sensor nodes. Nevertheless, its randomne... A great challenge faced by wireless sensor networks(WSNs) is to reduce energy consumption of sensor nodes. Fortunately, the data gathering via random sensing can save energy of sensor nodes. Nevertheless, its randomness and density usually result in difficult implementations, high computation complexity and large storage spaces in practical settings. So the deterministic sparse sensing matrices are desired in some situations. However,it is difficult to guarantee the performance of deterministic sensing matrix by the acknowledged metrics. In this paper, we construct a class of deterministic sparse sensing matrices with statistical versions of restricted isometry property(St RIP) via regular low density parity check(RLDPC) matrices. The key idea of our construction is to achieve small mutual coherence of the matrices by confining the column weights of RLDPC matrices such that St RIP is satisfied. Besides, we prove that the constructed sensing matrices have the same scale of measurement numbers as the dense measurements. We also propose a data gathering method based on RLDPC matrix. Experimental results verify that the constructed sensing matrices have better reconstruction performance, compared to the Gaussian, Bernoulli, and CSLDPC matrices. And we also verify that the data gathering via RLDPC matrix can reduce energy consumption of WSNs. 展开更多
关键词 data gathering regular low density parity check(RLDPC) matrix sensing matrix signal reconstruction wireless sensor networks(WSNs)
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Regularized canonical correlation analysis with unlabeled data 被引量:1
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作者 Xi-chuan ZHOU Hai-bin SHEN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第4期504-511,共8页
In standard canonical correlation analysis (CCA), the data from definite datasets are used to estimate their canonical correlation. In real applications, for example in bilingual text retrieval, it may have a great po... In standard canonical correlation analysis (CCA), the data from definite datasets are used to estimate their canonical correlation. In real applications, for example in bilingual text retrieval, it may have a great portion of data that we do not know which set it belongs to. This part of data is called unlabeled data, while the rest from definite datasets is called labeled data. We propose a novel method called regularized canonical correlation analysis (RCCA), which makes use of both labeled and unlabeled samples. Specifically, we learn to approximate canonical correlation as if all data were labeled. Then, we describe a generalization of RCCA for the multi-set situation. Experiments on four real world datasets, Yeast, Cloud, Iris, and Haberman, demonstrate that, by incorporating the unlabeled data points, the accuracy of correlation coefficients can be improved by over 30%. 展开更多
关键词 Canonical correlation analysis (CCA) regularization Unlabeled data Generalized canonical correlation analysis(GCCA)
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Effect of regularization parameters on geophysical reconstruction
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作者 Zhou Hui Wang Zhaolei +2 位作者 Qiu Dongling Li Guofa Shen Jinsong 《Petroleum Science》 SCIE CAS CSCD 2009年第2期119-126,共8页
In this paper we discuss the edge-preserving regularization method in the reconstruction of physical parameters from geophysical data such as seismic and ground-penetrating radar data. In the regularization method a p... In this paper we discuss the edge-preserving regularization method in the reconstruction of physical parameters from geophysical data such as seismic and ground-penetrating radar data. In the regularization method a potential function of model parameters and its corresponding functions are introduced. This method is stable and able to preserve boundaries, and protect resolution. The effect of regularization depends to a great extent on the suitable choice of regularization parameters. The influence of the edge-preserving parameters on the reconstruction results is investigated and the relationship between the regularization parameters and the error of data is described. 展开更多
关键词 Geophysical data INVERSION error of data regularization regularization parameters
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THE REGULARITY AND UNIQUENESS OF A GLOBAL SOLUTION TO THE ISENTROPIC NAVIER-STOKES EQUATION WITH ROUGH INITIAL DATA
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作者 王海涛 张雄韬 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1675-1716,共42页
A global weak solution to the isentropic Navier-Stokes equation with initial data around a constant state in the L^(1)∩BV class was constructed in[1].In the current paper,we will continue to study the uniqueness and ... A global weak solution to the isentropic Navier-Stokes equation with initial data around a constant state in the L^(1)∩BV class was constructed in[1].In the current paper,we will continue to study the uniqueness and regularity of the constructed solution.The key ingredients are the Holder continuity estimates of the heat kernel in both spatial and time variables.With these finer estimates,we obtain higher order regularity of the constructed solution to Navier-Stokes equation,so that all of the derivatives in the equation of conservative form are in the strong sense.Moreover,this regularity also allows us to identify a function space such that the stability of the solutions can be established there,which eventually implies the uniqueness. 展开更多
关键词 compressible Navier-Stokes equation BV initial data regularITY UNIQUENESS
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数据要素赋能新质生产力的法治展开 被引量:4
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作者 房慧颖 《东方法学》 北大核心 2025年第2期153-163,共11页
数据要素赋能新质生产力的基础是数据要素参与市场资源配置,科学的数据监管机制是数据要素高效参与市场化配置的法治保障。但是,目前的数据要素监管机制,存在包容性监管立场缺位、单向度监管模式主导、监管措施滞后性等缺陷,严重阻碍了... 数据要素赋能新质生产力的基础是数据要素参与市场资源配置,科学的数据监管机制是数据要素高效参与市场化配置的法治保障。但是,目前的数据要素监管机制,存在包容性监管立场缺位、单向度监管模式主导、监管措施滞后性等缺陷,严重阻碍了数据要素在推动新质生产力生成中作用的发挥。为克服前述缺陷,应当在法治框架下,以包容审慎的监管立场确立新型监管制度供给的基本框架;由单向度主导的监管模式转向协同监管体系,提升监管质效;创新适应监管需求的监管措施,凝聚多元监管工具的监管合力。通过以上措施,构建规范性与灵活性兼备且具有可操作性的数据要素监管机制,从而促进以数据要素为核心的生产力的转型与创新。 展开更多
关键词 新质生产力 数据要素 数据交易 数字平台 常态化监管 数字法治
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基于方面级情感分析与多源舆情融合的应急决策质量评价方法研究 被引量:1
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作者 郭海湘 张蓓佳 +1 位作者 赵甜甜 张文凯 《灾害学》 北大核心 2025年第3期95-103,共9页
该文针对传统应急决策质量评价方法在突发事件实时优化中的局限性,提出一种多源细粒度情感融合驱动的动态评价框架。以“12·18”积石山地震为例,融合多源舆情数据构建评价体系,结合RoBERTa-BiLSTM-Attention+AER模型及q-阶正交模... 该文针对传统应急决策质量评价方法在突发事件实时优化中的局限性,提出一种多源细粒度情感融合驱动的动态评价框架。以“12·18”积石山地震为例,融合多源舆情数据构建评价体系,结合RoBERTa-BiLSTM-Attention+AER模型及q-阶正交模糊融合技术,实现跨平台舆情情感的精准解析。结果表明:(1)模型在案例数据集上F1值达80.51%,较次优模型提高4.53%,实现在信息不完整情景下,精确识别公众意见及情感;(2)设计的多源舆情融合机制有效对冲平台偏差,融合前后两平台间的Cohen's d值从0.231降至0.133和0.117;(3)积石山地震的决策质量呈“初期高效响应—中期协调波动—后期恢复优化”的U型时序演化特征。提出的三维优化框架有助于应急管理从事后归因转向事中干预,为决策优化提供实时反馈。 展开更多
关键词 应急决策 多源数据 方面级情感分析 注意力熵正则化
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基于压缩感知的地震数据同时规则化和插值方法
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作者 董烈乾 周恒 +3 位作者 桑运云 曾庆芹 范红光 田永庆 《地球物理学进展》 北大核心 2025年第1期276-284,共9页
地震数据通常期望被放置在规则网格点上进行采集.但实际采集中会由于障碍物等因素的影响,导致采样点偏离预设网格点位置或者造成采样点的缺失.为了同时实现地震数据的偏点规则化与缺失数据的重构,本文基于压缩感知理论提出了一种新的数... 地震数据通常期望被放置在规则网格点上进行采集.但实际采集中会由于障碍物等因素的影响,导致采样点偏离预设网格点位置或者造成采样点的缺失.为了同时实现地震数据的偏点规则化与缺失数据的重构,本文基于压缩感知理论提出了一种新的数学模型,该模型基于融合采样算子,三维曲波变换以及快速迭代阈值算法,实现了对偏点数据和缺失数据的同时规则化和重构处理.融合采样算子结合了规则网格点的二值采样算子与纠正偏点的二维重心拉格朗日算子;快速迭代阈值算法可有效解决地震数据缺失反问题并提高算法的计算效率.应用该技术对模型和实际地震数据进行测试,验证了该方法在改善地震数据品质的优越性. 展开更多
关键词 压缩感知 融合采样 重心拉格朗日 快速迭代阈值 数据规则化和插值
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基于非规则格网的北极海冰三维可视化研究
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作者 叶萍萍 吴阿丹 +1 位作者 朱小文 张明虎 《遥感技术与应用》 北大核心 2025年第1期122-131,共10页
北极作为地球“三极”之一,蕴藏丰富资源,是全球变化研究的热点区域,其海冰变化对航道开通和生态保护具有重要意义。然而,现有三维虚拟地球(3D GIS)系统无法直接支持非规则格网的数据可视化,限制了北极航道信息服务能力。针对这一技术瓶... 北极作为地球“三极”之一,蕴藏丰富资源,是全球变化研究的热点区域,其海冰变化对航道开通和生态保护具有重要意义。然而,现有三维虚拟地球(3D GIS)系统无法直接支持非规则格网的数据可视化,限制了北极航道信息服务能力。针对这一技术瓶颈,本研究提出了一种将非规则格网数据自动转换为规则格网数据的方法。同时,研发了基于Cesium的海冰数据三维可视化系统,实现了长时间序列非规则格网海冰数据在三维虚拟地球系统中的自动加载和可视化。性能评估结果表明:该方法具有较高的精度和效率,研发系统能够高效和直观展现北极冰情变化,可为船舶航行规划提供重要冰情信息。 展开更多
关键词 数据可视化 数据转换 非规则格网数据 规则格网数据 虚拟三维地球
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基于数据挖掘探究桂金贵教授治疗小儿湿热内蕴型过敏性紫癜的用药规律
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作者 陈莉 李颖 +1 位作者 杜潘洁 汪永忠 《现代中药研究与实践》 2025年第2期78-83,89,共7页
目的探究桂金贵教授治疗小儿湿热内蕴型过敏性紫癜的用药规律及潜在的作用机制。方法收集2021年9月—2022年8月期间桂金贵教授治疗小儿湿热内蕴型过敏性紫癜的门诊处方。利用WPS Excel软件分析处方用药频次,研究药性、药味、归经和功效... 目的探究桂金贵教授治疗小儿湿热内蕴型过敏性紫癜的用药规律及潜在的作用机制。方法收集2021年9月—2022年8月期间桂金贵教授治疗小儿湿热内蕴型过敏性紫癜的门诊处方。利用WPS Excel软件分析处方用药频次,研究药性、药味、归经和功效,揭示用药规律,并应用关联分析、聚类分析、复杂网络分析等方法,筛选核心方药。利用公开数据库收集疾病靶点和核心中药靶点,构建核心药物作用于湿热内蕴型过敏性紫癜的PPI网络图;使用Cytocape 3.8.0中的cytohubba插件来筛选hub基因,利用ClueGO插件进行GO和KEGG富集分析,预测核心方药治疗湿热内蕴型过敏性紫癜的分子机制。结果桂金贵教授以牡丹皮、赤芍、白茅根、仙鹤草为核心方,以清热凉血、凉血止血、利水渗湿、活血化瘀为治法,从“肝”论治湿热内蕴型过敏性紫癜。其治疗机制可能通过IL-17信号通路,参与淋巴细胞代谢过程,改善HSP临床症状;通过TNF信号通路调节,抑制HSP诱导的血管内皮细胞凋亡,逆转HSP损伤;以达到标本兼治的目的。结论通过数据挖掘分析了桂金贵教授治疗小儿湿热内蕴型过敏性紫癜用药规律、核心方及作用机制,为临床用药提供理论支撑,同时为核心方的进一步研究与开发奠定基础。 展开更多
关键词 小儿湿热内蕴型过敏性紫癜 数据挖掘 网络药理学 用药规律 作用机制
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基于中医传承辅助平台的止痒方剂用药规律研究
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作者 李璐瑒 张鑫 +1 位作者 马园 胡欣燕 《实用皮肤病学杂志》 2025年第2期140-145,共6页
目的应用中医传承辅助平台对具有止痒功效的方剂数据进行挖掘分析,总结止痒方剂用药规律。方法收集2020年版《中华人民共和国药典》(一部)、《中药成方制剂》《中医方剂大辞典》《历代止痒方剂》中收载的止痒方剂,并运用中医传承辅助平... 目的应用中医传承辅助平台对具有止痒功效的方剂数据进行挖掘分析,总结止痒方剂用药规律。方法收集2020年版《中华人民共和国药典》(一部)、《中药成方制剂》《中医方剂大辞典》《历代止痒方剂》中收载的止痒方剂,并运用中医传承辅助平台V3.5的方剂分析功能,分析用药频次、中药功效、四气、五味、归经、核心药物及方剂聚类等,并对内服、外用2类方剂进行上述用药规律分析。结果收集到具有止痒功效的方剂共计429首,去除重复和无效数据后共纳入275首方剂,其中内服方剂99首,外用方剂176首,涉及中药226味,总频次共1730次,其中99首内服方剂用药频次927次,176首外用方剂用药频次803次;具有止痒功效的方剂以外用居多。防风、冰片分别为内服、外用止痒方剂使用频次最高的药物。在用药频次方面,所有止痒方剂和内服、外用止痒方剂三者差异较大,而在性味归经和功效方面,三者基本一致,药性寒温并用,药味多为辛、苦、甘,多入肺、心、脾、肝四经,以清热类中药使用频次居首。防风-甘草为所有止痒方剂和内服止痒方剂中使用频次最高的药对,冰片-炉甘石为外用止痒方剂中使用频次最高的药对。炉甘石→冰片、生地黄→当归、炉甘石→冰片分别为所有止痒方剂和内服、外用止痒方剂中置信度最高的关联规则。所有止痒方剂以及内服止痒方剂、外用止痒方剂分别生成5个核心类方组合。结论通过中医传承辅助平台获得了止痒方剂的用药规律,可为中医临床提供用药参考,亦可为中药新药研发提供依据。 展开更多
关键词 瘙痒症 止痒方剂 数据挖掘 聚类分析 用药规律
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基于“状态数据”常态监测高等职业学校高质量发展:可行性、实施困境及突破路径
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作者 吉国庆 《江西职业技术大学学报》 2025年第2期11-15,共5页
通过对全国高等职业学校人才培养工作状态数据采集与管理平台(以下简称“状态数据平台”)所采集到的“状态数据”进行深度挖掘与分析,常态监测高等职业学校高质量发展状态,为多元主体实施价值判断、开展科学决策提供客观依据。然而,当... 通过对全国高等职业学校人才培养工作状态数据采集与管理平台(以下简称“状态数据平台”)所采集到的“状态数据”进行深度挖掘与分析,常态监测高等职业学校高质量发展状态,为多元主体实施价值判断、开展科学决策提供客观依据。然而,当前高等职业学校面临认识和实践的双重困境,导致“状态数据”的常态监测功能没有得到充分发挥。高等职业学校需要重构认识体系和强化能力建设,用理性的、发展的、系统的思维对“状态数据”进行新的认知,构建“常态监测—及时诊断—持续改进”闭环逻辑,让“状态数据”焕发出新的价值功用,使常态监测成为高等职业学校高质量发展的重要支撑。 展开更多
关键词 状态数据 常态监测 高质量发展 高等职业学校
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高维局部数据体中线性信号预测基本理论与方法
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作者 王华忠 项健 +2 位作者 张力起 欧阳志远 宋家文 《石油物探》 北大核心 2025年第1期1-14,共14页
首先,提出了若干线性结构(可以视为局部平面波)飘在具有不同概率分布特征的、实测的局部高维数据体中是地震信号处理的核心概念模式,认为对局部高维数据体中的线性结构进行建模及最佳预测,从而解决去噪、数据规则化和解混叠(Deblending... 首先,提出了若干线性结构(可以视为局部平面波)飘在具有不同概率分布特征的、实测的局部高维数据体中是地震信号处理的核心概念模式,认为对局部高维数据体中的线性结构进行建模及最佳预测,从而解决去噪、数据规则化和解混叠(Deblending)等问题是地震数据处理中的基本环节;认为对线性信号进行最佳的建模和预测包括模型驱动和数据驱动的方法。前者是由预先选定的局部平面波基函数的线性叠加表示局部高维数据体中包含的信号;后者由数据矩阵(张量)分解的方法推断局部高维数据体中包含的线性结构。然后,全面分析了频率-空间域高维Wiener滤波方法、自相关矩阵及Hankel矩阵正交分解方法(SSA方法)、高维线性Radon变换方法(高维Beamforming方法)和张量分解方法的基本理论,为进行局部高维数据体中线性信号预测及各种应用奠定了理论基础。最后,指出山前带及其他复杂地表探区实际数据中的相干噪声和非相干噪声往往不符合线性信号建模及预测的理论假设条件,因而必须发展非线性去噪方法。 展开更多
关键词 局部高维数据体 线性结构 最佳预测 高维Wiener滤波方法 高维SSA方法 高维线性Radon变换方法 张量分解方法 去噪与数据规则化
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基于Inverted-B+树的海量三维地质块体模型高效索引方法 被引量:1
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作者 陈根深 刘刚 +3 位作者 董洋 范文遥 易强 姜子鑫 《计算机科学》 北大核心 2025年第8期146-153,共8页
三维地质块体模型中大量的零值或空值使得基于B+树的属性索引结构频繁分裂和调整,导致索引维护成本高;同时,B+树的单向链表结构加剧了大规模块体模型中数据顺序遍历和范围查询效率低下的问题。为此,提出了一种基于Inverted-B+树(IBT)的... 三维地质块体模型中大量的零值或空值使得基于B+树的属性索引结构频繁分裂和调整,导致索引维护成本高;同时,B+树的单向链表结构加剧了大规模块体模型中数据顺序遍历和范围查询效率低下的问题。为此,提出了一种基于Inverted-B+树(IBT)的索引方法。该方法通过构建IBT索引结构,在将重复键插入叶子节点时,为每个重复键创建倒排节点,从而有效减少了数据处理中的结构调整。通过在内部节点存储中间索引值来加速查询过程,并在叶子节点和倒排节点之间建立双向链表,实现了从任意叶子节点按顺序访问整个数据集从而进行高效的范围查询。利用三维地质结构模型经过体元剖分、插值和降维处理所得到的6个块体模型进行测试,结果表明:与传统B+树相比,IBT方法在索引构建时间、空间占用和查询性能方面均有显著提升,特别是在处理大规模数据集中,其索引构建效率提升了71%,空间占用减少了83%,查询效率得到了显著提升。 展开更多
关键词 Inverted-B+树 规则块体 三维地质模型 空间数据管理 空间索引
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