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A reweighted damped singular spectrum analysis method for robust seismic noise suppression

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Petroleum Science 2024年第3期21卷 1671-1682页

作者： wei-lin Huang Yan-Xin Zhou Yang Zhou wei-jie Liu Ji-Dong Li State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China SINOPEC Petroleum Exploration and Production Research Institute Beijing102206China SINOPEC Geophysical Research Institute Nanjing211103jiangsuChina

(Multichannel)Singular spectrum analysis is considered as one of the most effective methods for seismic incoherent noise *** utilizes the low-rank feature of seismic signal and regards the noise suppression as a low-rank reconstruction ***,in some cases the seismic geophones receive some erratic disturbances and the amplitudes are dramatically larger than other *** presence of this kind of noise,called erratic noise,makes singular spectrum analysis(SSA)reconstruction unstable and has undesirable effects on the final *** robustify the low-rank reconstruction of seismic data by a reweighted damped SSA(RD-SSA)*** incorporates the damped SSA,an improved version of SSA,into a reweighted *** damping operator is used to weaken the artificial disturbance introduced by the low-rank projection of both erratic and random *** central idea of the RD-SSA method is to iteratively approximate the observed data with the quadratic norm for the first iteration and the Tukeys bisquare norm for the rest *** RD-SSA method can suppress seismic incoherent noise and keep the reconstruction process robust to the erratic *** feasibility of RD-SSA is validated via both synthetic and field data examples.

关键词： Singular spectrum analysis Damping operator Seismic erratic noise Seismic signal processing Robust low-rank reconstruction

Micro segment analysis of supercritical methane thermal-hydraulic performance and pseudo-boiling in a PCHE straight channel

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Petroleum Science 2024年第2期21卷 1275-1289页

作者： Qian Li Zi-jie lin Liu Yang Yue Wang Yue Li wei-Hua Cai Laboratory of Thermo-Fluid Science and Nuclear Engineering Northeast Electric Power UniversityJilin132000JilinChina School of Energy and Power Engineering Northeast Electric Power UniversityJilin132000JilinChina

The printed circuit heat exchanger(PCHE) is receiving wide attention as a new kind of compact heat exchanger and is considered as a promising vaporizer in the LNG process. In this paper, a PCHE straight channel in the length of 500 mm is established, with a semicircular cross section in a diameter of 1.2 *** simulation is employed to investigate the flow and heat transfer performance of supercritical methane in the channel. The pseudo-boiling theory is adopted and the liquid-like, two-phase-like, and vapor-like regimes are divided for supercritical methane to analyze the heat transfer and flow *** results are presented in micro segment to show the local convective heat transfer coefficient and pressure drop. It shows that the convective heat transfer coefficient in segments along the channel has a significant peak feature near the pseudo-critical point and a heat transfer deterioration when the average fluid temperature in the segment is higher than the pseudo-critical point. The reason is explained with the generation of vapor-like film near the channel wall that the peak feature related to a nucleateboiling-like state and heat transfer deterioration related to a film-boiling-like state. The effects of parameters, including mass flow rate, pressure, and wall heat flux on flow and heat transfer were *** calculating of the averaged heat transfer coefficient of the whole channel, the traditional method shows significant deviation and the micro segment weighted average method is adopted. The pressure drop can mainly be affected by the mass flux and pressure and little affected by the wall heat flux. The peak of the convective heat transfer coefficient can only form at high mass flux, low wall heat flux, and near critical pressure, in which condition the nucleate-boiling-like state is easier to appear. Moreover,heat transfer deterioration will always appear, since the supercritical flow will finally develop into a filmboiling-like state. So hea

关键词： Printed circuit heat exchanger Vaporization Supercritical methane Pseudo-boiling Micro segment analysis

Autofocus by Lissajous scanning in time reversal optical scanning holography

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Chinese Optics Letters 2024年第8期22卷 13-20页

作者： jie Liu Haiyan Ou Hua Wang lin Peng wei Shao Shenzhen Institute for Advanced Study University of Electronic Science and Technology of ChinaShenzhen 518000China School of Physics University of Electronic Science and Technology of ChinaChengdu 611731China Key Laboratory of Cognitive Radio and Information Processing Guilin University of Electronic TechnologyGuilin 541004China

In this Letter, an autofocusing method in optical scanning holography(OSH) system is proposed. By introducing Lissajous scanning into multiple signal classification(MUSIC) method in time-reversal(TR) OSH, the axial locations of the targets can be retrieved with better resolution and the peak prominence increases from 0.21 to 0.34. The feasibility of this method is confirmed by simulation as well as experiment.

关键词： digital holography Lissajous scanning image reconstruction axial localization

Serum monoterpene levels, glucose homeostasis, lipid profiles, and metabolic syndrome in adults: NHANES, 2013–2014

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Emerging Contaminants 2024年第2期10卷 33-39页

作者： wei-jie Wang Yu-ling lin Chikang Wang Chien-Yu lin Division of Nephrology Department of Internal MedicineTaoyuan General HospitalMinistry of Health and WelfareTaoyuan330TaiwanChina Department of Biomedical Engineering Chung Yuan Christian UniversityTaoyuan300TaiwanChina Department of Nephrology Hsinchu Cathay General HospitalHsinchu300TaiwanChina Department of Healthcare Management Yuanpei University of Medical TechnologyHsinchu300TaiwanChina Department of Environmental Engineering and Health Yuanpei University of Medical TechnologyHsinchu300TaiwanChina Department of Internal Medicine En Chu Kong HospitalNew Taipei City237TaiwanChina School of Medicine Fu Jen Catholic UniversityNew Taipei City242TaiwanChina

Monoterpenes are organic compounds which have been studied for their medicinal ***,the association between monoterpene exposure and metabolic parameters in humans is *** investigated the connection between three specific monoterpenes(α-pinene,β-pinene,and limonene),glucose homeostasis biomarkers,lipid profiles,and metabolic syndrome(MS)in 1627 adults from the National Health and Nutrition Examination Survey(NHANES)2013–*** found serum levels ofα-pinene andβ-pinene were positively associated with fasting glucose,total cholesterol,triglyceride,and apolipoprotein *** addition,increased levels of limonene andΣmonoterpene(sum of three monoterpene chemicals)were linked to higher insulin,β-cell function,total cholesterol,low density lipoprotein cholesterol(LDL-C),triglycerides,and apolipoprotein *** with all three monoterpenes above the 50th percentile had notably higher values for total cholesterol and triglycerides compared to those with all three monoterpenes below the 50th percentile(P for trendlinked to an increased risk of high-density lipoprotein cholesterol(HDL-C)insufficiency and *** concentrations ofβ-pinene were associated with a higher prevalence of ***,increased levels of limonene andΣmonoterpene were connected to a higher risk of MS,larger waist circumference,low HDL-C,hypertriglyceridemia,and higher blood pressure according to MS *** conclusion,serum monoterpenes levels were linked to glucose regulation,lipid profiles,and indicators of *** studies are necessary to clarify the potential causal relationships.

关键词： Glucose homeostasis Lipid profiles Monoterpenes National health and nutrition examination survey(NHANES)

The Existence of a Meridional Curve in Closed Incompressible Surfaces in Fully Alternating link Complements

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Chinese Annals of Mathematics,Series B 2024年第1期45卷 73-80页

作者： wei lin School of Mathematical Sciences Dalian University of TechnologyDalian 116024LiaoningChina

Menasco showed that a closed incompressible surface in the complement of a non-split prime alternating link in S^(3) contains a circle isotopic in the link complement to a meridian of the *** on this result,he was able to argue the hyperbolicity of non-split prime alternating links in *** et *** that if F■S×I\L is an essential torus,then F contains a circle which is isotopic in S×I\L to a meridian of *** author generalizes his result as follows:Let S be a closed orientable surface,L be a fully alternating link in S×I\If F ■ S×I\L is a closed essential surface,then F contains a circle which is isotopic in S×I\L to a meridian of L.

关键词： Fully alternating Incompressible surfaces Meridionally incompressible

Study of baryon number transport dynamics and strangeness conservation effects using Ω-hadron correlations

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Nuclear Science and Techniques 2024年第7期35卷 147-156页

作者： wei-jie Dong Xiao-Zhou Yu Si-Yuan Ping Xia-Tong Wu Gang Wang Huan-Zhong Huang Zi-wei lin Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China Department of Physics and Astronomy University of CaliforniaLos AngelesCA 90095USA Department of Physics East Carolina UniversityGreenvilleNC 27858USA

In nuclear collisions at RHIC energies, an excess of Ω hyperons over ■ is observed, indicating that Ω has a net baryon number despite s and s quarks being produced in pairs. The baryon number in Ω may have been transported from the incident nuclei and/or produced in the baryon-pair production of Ω with other types of anti-hyperons such as Ξ. To investigate these two scenarios, we propose to measure the correlations between Ω and K and between Ω and anti-hyperons. We use two versions, the default and string-melting, of a multiphase transport(AMPT) model to illustrate the method for measuring the correlation and to demonstrate the general shape of the correlation. We present the Ω-hadron correlations from simulated Au+Au collisions at ■ =7.7 and 14.6 Ge V and discuss the dependence on the collision energy and on the hadronization scheme in these two AMPT versions. These correlations can be used to explore the mechanism of baryon number transport and the effects of baryon number and strangeness conservation on nuclear collisions.

关键词： Baryon number transport Strangeness conversation Correlation Gluon junction

不对中故障下带挤压油膜阻尼器的滚动轴承转子系统的动力学分析（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2016年第8期17卷 614-631页

作者： Liang MA Jun-hong ZHANG jie-wei lin Jun WANG Xin LU State Key Laboratory of Engines Tianjin University Tianjin 300072 China Renal College Tianjin University Tianjin 300072 China Institute of Sound and Vibration Research University of Southampton Southampton SO171BJ UK

目的:工业的不断发展对航空发动机、泵、燃气轮机等旋转机械的动力性能提出了更高的要求。转子系统是旋转机械的重要组成部分。复杂的转子系统在高速运转时会产生故障和非线性振动,从而影响系统的可靠性。因此,开展转子系统的非线性动... 详细信息

目的:工业的不断发展对航空发动机、泵、燃气轮机等旋转机械的动力性能提出了更高的要求。转子系统是旋转机械的重要组成部分。复杂的转子系统在高速运转时会产生故障和非线性振动,从而影响系统的可靠性。因此,开展转子系统的非线性动力性研究,研究转子系统在高速运转时的非线性响应及其抑制作用对转子系统的设计和故障诊断具有重要的意义。创新点:1.在建模的时候考虑转子系统的实际结构,在不对中模型中引入齿式联轴器啮合力,在滚动轴承模型中考虑弹流润滑影响;2.探究挤压油膜阻尼器参数对转子系统非线性特性抑制的影响,总结其变化规律。方法:1.基于Hertz接触和弹流润滑理论,建立滚动轴承动力学模型,同时考虑齿式联轴器齿之间的啮合力,建立不对中故障下的齿式联轴器啮合力模型,并在此基础上,根据转子系统的支撑形式,建立0-2-1支撑的转子动力学模型;2.开展转子动力学实验,验证模型的准确性并分析不对中量对系统频谱特性的影响;3.在分析不对中故障非线性特性的基础上,研究挤压油膜阻尼器参数对于非线性特性抑制的作用。结论:1.齿式联轴器啮合作用和滚动轴承的弹流润滑对不对中故障下转子系统的失稳产生一定的影响,润滑会导致系统发生分岔的窗口推迟;2.对于转子系统的弹性支撑,其一阶临界转速和振幅随着刚度的增大而增大,选择合适的刚度有利于转子系统的稳定运行;3.挤压油膜阻尼器的参数对转子系统故障引起的非线性具有较好的抑制作用,其作用的大小取决于不对中量和挤压油膜阻尼器的油膜间隙的耦合,合理地调节油膜间隙有助于增大系统的稳定区间范围。

关键词：挤压油膜阻尼器齿式联轴器滚动轴承弹流润滑非线性动力学不对中故障

Thickness dependence of superconductivity in layered GeP_(5)

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Rare Metals 2024年第3期43卷 1323-1328页

作者： lin Wu Ke-Meng Yang wei Gan Rui-Chun Xiao Ya-jie Dai Xi Tang Hong lin Hui Han Hui Li Information Materials and Intelligent Sensing Laboratory of Anhui Province Institute of Physical Science and Information TechnologyAnhui UniversityHefei230601China

Understanding the relationship between dimensionality and superconductivity has attracted substantial research *** this work,we report the effective modulation of superconductivity in GeP_(5)through *** superconducting phase transition temperature improves by~10%as the thickness of GeP_(5)decreases from bulk to~96 nm,behaving as a unique negative relationship between the superconducting phase transition temperatureand thickness.

关键词： superconductivity dimensionality

Hepatic perivascular epithelioid cell tumors:The importance of preoperative diagnosis

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World Journal of Gastroenterology 2024年第13期30卷 1926-1933页

作者： Shuai Yan Jia-jie Lu lin Chen wei-Hua Cai Jin-Zhu Wu Department of Medical School Nantong UniversityNantong 226300Jiangsu ProvinceChina Department of Hepatobiliary Surgery Affiliated Nantong Hospital 3 of Nantong UniversityNantong 226006Jiangsu ProvinceChina Nantong Institute of Liver Disease Affiliated Nantong Hospital 3 of Nantong UniversityNantong 226006Jiangsu ProvinceChina

Accurate preoperative diagnosis is highly important for the treatment of perivascular epithelioid cell tumors(PEComas)because PEComas are mainly benign tumors and may not require surgical *** analyzing the causes,properties and clinical manifestations of PEComas,we summarize the challenges and solutions in the diagnosis of PEComas.

关键词： Hepatic perivascular epithelioid cell tumors Liver Preoperative diagnosis Angiomyolipomas Mesenchymal tissue-derived tumors