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Detecting the Relationship Between Summer Rainfall Anomalies in Eastern China and the SSTA in the Global Domain with a New Significance Test Method

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Journal of Ocean University of China 2009年第1期8卷 15-22页

作者： LU chuhan GUAN Zhaoyong wang Panxing DUAN Mingken Department of Atmospheric Science Nanjing University of in formation Science and TechnologyNanjing 210044 P. R. China

It is suggested that the multiple samples in a correlation map or a set of correlation maps should be examined with significance tests as per the Bernoulli probability model. Therefore, both the contemporaneous and lag correlations of summertime precipitation R in any one of the three regions of Northern China （NC）, the Changjiang-Huaihe River Valley （CHRV）, and Southern China （SC） with the SSTA in the global domain have been tested in the present article, using our significance test method and the method proposed by Livezey and Chen （1983） respectively. Our results demonstrate that the contemporaneous correlations of sum- mer R in CHRV with the SSTA are larger than those in NC. Significant correlations of SSTA with CHRV R are found to be in some warm SST regions in the tropics, whereas those of SSTA with NC R, which are opposite in sign as compared to the SSTA-CHRVR correlations, are found to be in some regions where the mean SSTs are low. In comparison with the patterns of the contemporaneous correlations, the 1 to 12 month lag correlations between NC R and SSTA, and those between CHRV summer R and SSTA show similar patterns, including the magnitudes and signs, and the spatial distributions of the coefficients. However, the summer rainfall in SC is not well correlated with the SSTA, no matter how long the lag interval is. The results derived from the observations have set up a relationship frame connecting the precipitation anomalies in NC, CHRV, and SC with the SSTA in the global domain, which is critically useful for our understanding and predicting the climate variabilities in different parts of China. Both NC and CHRV summer R are connected with E1 Nifio events, showing a ‘- -＇pattern in an E1 Nifio year and a‘＋＋＇ pattern in the subsequent year. Key words summer precipitation; eastern China; global sea surface

关键词： temperature contemporaneous correlation time lag correlation significance test for multiple correlation maps

Research on High Precision Borehole Temperature Measurement Technology

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Acta Geologica Sinica(English Edition) 2024年第S1期98卷 81-83页

作者： ZHANG Bing ZHU Xiaoyi wang Xiaolei XING Lili XUE Bing LI Jiang GAO Shanghua SU Peng wang Yuru wang chuhan Institute of Earthquake Forecasting China Earthquake AdministrationBeijing 100036China Institute of Disaster Prevention SanheHebei 065201China

From 2019 to 2021,China Seismic Experimental Site has built twelve 300 m deep well multi-measurement comprehensive observation stations in the cross-fault area of the Aninghe-Zemuhe fault zone,integrating BBVS120 very broadband borehole seismometer,RZB four-gauge borehole strainmeter and geothermometer with resolution up to 0.0001℃.The borehole diameter is 150 mm and the inner diameter of the sleeve is 130 *** multi-item integrated observation system is divided into two parts:underground and *** downhole part is mainly composed of sensor and power supply signal isolation.

关键词： high-precision borehole thermometer downhole integrated observation seismic science experiment field

Measurement and Analysis of Vibration Effect of Free-falling Corner Cube Driving Mechanism in Free Fall Absolute Gravimeter

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Acta Geologica Sinica(English Edition) 2024年第S1期98卷 84-86页

作者： ZHANG Bing ZHU Xiaoyi WU Qiong XUE Bing XING Lili WU Yanxiong SU Peng wang Xiaolei wang Yuru wang chuhan Institute of Earthquake Forecasting China Earthquake AdministrationBeijing 100036China Institute of Geophysics China Earthquake AdministrationBeijing 100081China Institute of Disaster Prevention SanheHebei 065201China

The vibration interference of the reference corner cube runs through the free flight process of the free-falling corner cube,which is superimposed on the whole laser interference ***,it is necessary to solve the inter... 详细信息

关键词： laser interference absolute gravimeter gravity measurement vibration influence

An adult patient of X-linked hypophosphatemia with joint manifestation mimicking spondylarthritis

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Chinese Medical Journal 2022年第10期135卷 1255-1257页

作者： chuhan wang Jiuliang Zha Hongbo Yang Yan Jiang Yan Zha Weibo Xia Department of Rheumatology and Clinical Immunology Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China National Clinical Research Center for Dermatologic and Immunologic Diseases(NCRC-DID) Ministry of Science and TechnologyBeijing 100730China State Key Laboratory of Complex Severe and Rare Diseases Peking Union Medical College Hospital(PUMCH)Beijing 100730China Key Laboratory of Rheumatology and Clinical Immunology Ministry of EducationBeijing 100730China Department of Endocrinology and Key Laboratory of Endocrinology National Health CommissionPeking Union Medical College Hospital(PUMCH)Peking Union Medical College and Chinese Academy of Medical SciencesBeijing 100730China

To the Editor:X-linked hypophosphatemia(XLH)is a rare hereditary metabolic disorder characterized by hypophos-phatemic rickets associated with phosphate wasting.[1]It is caused by a loss-of-function mutation in the PHEX(Phosphate regulating gene with Homology to Endopepti-dases located on the X chromosome)gene.[2]The clinical manifestations of the adult patient are usually not specific,often including bone pain,muscle weakness,and so on.

关键词： patient clinical adult

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理性亚格子建模的实践与反思

计算物理 2018年第3期35卷 253-261页

作者：方乐王楚涵北京航空航天大学中法工程师学院北京100191 北京航空航天大学先进航空发动机协同创新中心北京100191 北京航空航天大学中法联合实验室北京100191

亚格子建模是大涡模拟中的核心问题之一.理性亚格子建模的初衷是为尽量去除建模过程中的经验和唯象的成分,让建模过程中的每一步都在物理和数学上有迹可循.根据理性亚格子建模的理论已经发展出一系列不依赖经验常数和唯象模型的亚格子模... 详细信息

亚格子建模是大涡模拟中的核心问题之一.理性亚格子建模的初衷是为尽量去除建模过程中的经验和唯象的成分,让建模过程中的每一步都在物理和数学上有迹可循.根据理性亚格子建模的理论已经发展出一系列不依赖经验常数和唯象模型的亚格子模型,但在实际问题中的效果却仍有不足,从而引发了近年来对亚格子建模思想本身的反思.本文回顾已有的研究和新的进展,目标是对未来的大涡模拟给出理性且自洽的理论指导.

关键词：亚格子建模大涡模拟理性建模柯氏方程数学兼容性

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穿层爆破各煤层动态应力分布与抽放效果探讨

岩石力学与工程学报 2012年第A1期31卷 2989-2996页

作者：龚敏熊本良王楚翰王华北京科技大学土木与环境工程学院北京100083 四川省古叙煤业开发公司四川泸洲646000

穿层深孔爆破在石门揭煤及局部地段防止瓦斯突出有重要作用,由于爆破区域跨越多层煤、岩介质以及扇形布孔造成孔口孔底最小抵抗线不相等因素影响,穿层深孔爆破研究较为困难。在大量矿井试验基础上,利用三维数值模拟方法,研究有代表意义... 详细信息

穿层深孔爆破在石门揭煤及局部地段防止瓦斯突出有重要作用,由于爆破区域跨越多层煤、岩介质以及扇形布孔造成孔口孔底最小抵抗线不相等因素影响,穿层深孔爆破研究较为困难。在大量矿井试验基础上,利用三维数值模拟方法,研究有代表意义的穿层深孔爆破相关理论问题。建立穿层爆破计算模型,获得不同位置抽放孔有效应力随时间变化规律;探讨各抽放孔有效应力随距炮孔水平距离增加而衰减,以及不同抽放孔轴线方向两层煤中应力分布的差异。计算结果表明:复合介质孔口、孔底煤层中爆破裂隙贯通范围分别为1.4,1.8 m;孔底由于锥形波的叠加和应力波反射双重作用影响,在相同距离时孔底有效应力平均值较孔口大73%;煤–岩复合介质中煤层爆破效果优于单煤层爆破效果,同等情况下,复合介质煤层中孔口处有效应力极值较单煤层增加17%～42%,孔底增加6%～24%。现场实践表明,当作用在抽放孔轴线的平均有效应力由7.12 MPa增到12 MPa后,瓦斯抽放总量增加3倍以上。

关键词：采矿工程穿层爆破煤–岩介质扇形布孔数值计算

A Dual Estimate Tracking Based Multipath Mitigation Method for BOC signals

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A Dual Estimate Tracking Based Multipath Mitigation Method f...

第九届中国卫星导航学术年会

作者： chuhan wang Yang Gao Xiaowei Cui Mingquan Lu Electronic Engineering Department Tsinghua University

Binary Offset Carrier(BOC) modulated signal, which will widely be used in next generation Global Navigation Satellite Systems(GNSS), has multi peaks in the auto-correlation function. In practical application condition, multipath and ambiguity are two main problems that can serious degrade the GNSS receiver ranging precision due to the feature of multi peaks. To solve the ambiguity problem, we typically adopt Dual Estimate Tracking(DET) that treats the subcarrier of BOC signals independently and tracks it by an additional loop. However, the multipath mitigation of DET structure is not specially considered yet due to the complex features of two-dimension cross-correlation function. In this paper, we propose a DET based multipath mitigation method for BOC signals, which mitigates the direct influence by an earlier phase Pseudo-Noise code instead of the prompt for subcarrier locked loop(SLL) and the indirect influence by the Double Delta(DD) method for delay locked loop(DLL). A simulated experiment based on a software receiver is designed to validate the feasibility of the multipath mitigation method and the results show that this method can significant reduce the short and mediate range delay multipath error at the expense of increasing the long range delay multipath error a little. This method can also achieve the compromise between multipath and noise performance by adjusting the local Pseudo-Noise code phase for different application scenarios.

关键词： mitigation binary offset carrier software receiver dual estimate tracking

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集成因子分解机及其在论文推荐中的应用研究

数据分析与知识发现 2023年第8期7卷 128-137页

作者：杨辰郑若桢王楚涵耿爽王楠深圳大学管理学院深圳518060

【目的】针对现有论文推荐方法在处理论文作者映射关系稀疏和特征表达时存在成效不足的问题,开发一种基于因子分解机和集成学习的新型论文推荐框架。【方法】使用卷积神经网络、网络嵌入等方法处理数据获取特征表示,将特征矩阵输入因子... 详细信息

【目的】针对现有论文推荐方法在处理论文作者映射关系稀疏和特征表达时存在成效不足的问题,开发一种基于因子分解机和集成学习的新型论文推荐框架。【方法】使用卷积神经网络、网络嵌入等方法处理数据获取特征表示,将特征矩阵输入因子分解机,引入随机子空间法集成训练模型,最后通过投票机制协同后输出推荐结果。【结果】基于CiteULike数据集的实验结果表明,本文方法的推荐精确率、准确率和F度量分别为72.6%、69.7%和76.2%,分别比基准算法提升高于20个百分点、15个百分点和9个百分点。【局限】负采样过程中缺乏正负样本语义相似性的考虑,在模型的输入构造、特征处理模式方面有待进一步探究。【结论】集成因子分解机能在数据稀疏情况下实现特征的有效表示和利用,从而提升推荐效果。

关键词：论文推荐因子分解机集成学习

Effect of selenium supplementation on apoptosis and cell cycle blockage of renal cells in broilers fed a diet containing aflatoxin B1

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Effect of selenium supplementation on apoptosis and cell cyc...