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A regression approach for seismic first-break picking

Petroleum Science 2024年第3期21卷 1584-1596页

作者： Huan yuan san-Yi yuan Jie Wu Wen-Jing sang Yu-He Zhao CNPC Key Laboratory of Geophysical Exploration China University of Petroleum(Beijing)Beijing 102249China Research Institute of Petroleum Exploration&Development—Northwest(NWGI) Key Laboratory of reservoir characterization of CNPCPetroChinaLanzhou 730020GansuChina

The picking efficiency of seismic first breaks(FBs)has been greatly accelerated by deep learning(DL)***,the picking accuracy and efficiency of DL methods still face huge challenges in low signal-to-noise ratio(SNR)*** address this issue,we propose a regression approach to pick FBs based on bidirectional long short-term memory(Bi LSTM)neural network by learning the implicit Eikonal equation of 3D inhomogeneous media with rugged topography in the target *** employ a regressive model that represents the relationships among the elevation of shots,offset and the elevation of receivers with their seismic traveltime to predict the unknown FBs,from common-shot gathers with sparsely distributed *** from image segmentation methods which automatically extract image features and classify FBs from seismic data,the proposed method can learn the inner relationship between field geometry and *** addition,the predicted results by the regressive model are continuous values of FBs rather than the discrete ones of the binary *** picking results of synthetic data shows that the proposed method has low dependence on label data,and can obtain reliable and similar predicted results using two types of label data with large *** picking results of9380 shots for 3D seismic data generated by vibroseis indicate that the proposed method can still accurately predict FBs in low SNR *** subsequent stacked profiles further illustrate the reliability and effectiveness of the proposed *** results of model data and field seismic data demonstrate that the proposed regression method is a robust first-break picker with high potential for field application.

关键词： First-break picking Low signal-to-noiseratio Regression BiLSTM Traveltime Geometry Noisy seismic data

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Enhancing thermoelectric performance of p-type SnTe through manipulating energy band structures and decreasing electronic thermal conductivity

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Rare Metals 2024年第7期43卷 3232-3241页

作者： Xin Qian Hao-Ran Guo Jia-Xin Lyu Bang-Fu Ding Xing-yuan san Xiao Zhang Jiang-Long Wang Shu-Fang Wang Hebei Key Lab of Optic-Electronic Information and Materials College of Physics Science and TechnologyHebei UniversityBaoding 071002China College of Electron and Information Engineering Hebei UniversityBaoding 071002China Research Institute for Frontier Science Beihang UniversityBeijing100191China

SnTe has received considerable attention as an environmentally friendly alternative to the representative thermoelectric material of ***,excessive hole carrier concentration in SnTe results in an extremely low Seebeck coefficient and high thermal conductivity,which makes it exhibit relatively inferior thermoelectric *** this work,the thermoelectric performance of p-type SnTe is enhanced through regulating its energy band structures and reducing its electronic thermal conductivity by combining Bi doping with CdSe ***,the carrier concentration of SnTe is successfully suppressed via Bi doping,which significantly decreases the electronic thermal ***,the convergence and flattening of the valence bands by alloying CdSe effectively improves the effective mass of SnTe while restraining its carrier ***,a maximum figure of merit(ZT) of~ 0.87 at 823 K and an average ZT of~ 0.51 at 300-823 K have been achieved in Sn_(0.96)Bi_(0.04)Te-5%*** results indicate that decreasing the electronic thermal conductivity is an effective means of improving the performance of thermoelectric materials with a high carrier concentration.

关键词： Thermoelectric materials SnTe Energy band structure Electronic thermal conductivity ZT value

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Functionalization of covalent organic frameworks via multicomponent reactions

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Science China Chemistry 2024年

作者： Xue-Hui Liu Peng-Lai Wang Wei Wang san-yuan Ding State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering MOE Frontiers Science Center for Rare Isotopes Lanzhou University

Functionalized covalent organic frameworks (COFs) represent a fascinating class of porous materials that have attracted widespread interest due to their modifiable structures and impressive potential applications. However, the construction of functionalized COFs remains difficult as it requires simultaneous consideration of robust linkages, diversified structures, and tailorable functionalities. Recently, the introduction of multicomponent reactions (MCRs) into COF synthesis opens new avenues for creating highly stable and function-oriented COF materials, marking a significant advance in the development of COFs. This minireview summarizes the types of MCRs used in COF synthesis, highlights the functionalization strategies of COFs via MCRs, and provides insights on the key challenges and future frontiers in this field.

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Novel subtype of obesity influencing the outcomes of sleeve gastrectomy:Familial aggregation of obesity

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World Journal of Gastroenterology 2024年第13期30卷 1887-1898页

作者： Ze-Yu Wang Yun-Fei Qu Tian-Ming Yu Zeng-Lin Liu Yu-Gang Cheng Ming-Wei Zhong san-yuan Hu Department of General Surgery The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan HospitalJinan 250000Shandong ProvinceChina Department of Postgraduate Shandong First Medical University and Shandong Academy of Medical SciencesJinan 250000Shandong ProvinceChina Department of General Surgery Shandong Provincial Qianfoshan HospitalCheeloo College of Medicine Shandong UniversityJinan 250000Shandong ProvinceChina State Key Laboratory of Integration and Innovation of Classic Formula and Modern Chinese Medicine Lunan Pharmaceutical Group Co.Ltd.Linyi 276005Shandong ProvinceChina

BACKGROUND Differences in the preoperative characteristics and weight loss outcomes after sleeve gastrectomy(SG)between patients with familial aggregation of obesity(FAO)and patients with sporadic obesity(SO)have not been *** To explore the impact of SG on weight loss and the alleviation of obesity-related comorbidities in individuals with *** A total of 193 patients with obesity who underwent SG were *** with FAO/SO were matched 1:1 by propensity score matching and were categorized into 4 groups based on the number of first-degree relatives with obesity(1 SO vs 1FAO,2SO vs 2FAO).The baseline characteristics,weight loss outcomes,prevalence of obesity-related comorbidities and incidence of major surgeryrelated complications were compared between *** We defined FAO as the presence of two or more first-degree relatives with *** with FAO did not initially show significant differences in baseline data,short-term postoperative weight loss,or obesity-related comorbidities when compared to patients with SO ***,distinctions between the two groups became evident at the two-year mark,with statistically significant differences in both percentage of total weight loss(P=0.006)and percentage of excess weight loss(P<0.001).The FAO group exhibited weaker remission of type 2 diabetes mellitus(T2DM)(P=0.031),hyperlipidemia(P=0.012),and non-alcoholic fatty liver disease(NAFLD)(P=0.003)as well as a lower incidence of acid reflux(P=0.038).CONCLUSION FAO patients is associated with decreased mid-to-long-term weight loss outcomes;the alleviation of T2DM,hyperlipidemia and NAFLD;and decreased incidence of acid reflux postoperatively.

关键词： Obesity Bariatric surgery Sleeve gastrectomy Family history Weight loss

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A seismic elastic moduli module for the measurements of low-frequency wave dispersion and attenuation of fluid-saturated rocks under different pressures

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Petroleum Science 2024年第1期21卷 162-181页

作者： Yan-Xiao He Shang-Xu Wang Gen-Yang Tang Chao Sun Hong-Bing Li san-Yi yuan Xian Wei Li-Deng Gan Xiao-Feng Dai Qiang Ge Peng-Peng Wei Hui-Qing Zhang National Key Laboratory of Petroleum Resources and Engineering CNPC Key Lab of Geophysical ExplorationCollege of GeophysicsChina University of Petroleum(Beijing)Beijing102249China School of Resources and Geosciences China University of Mining and TechnologyXuzhou221116JiangsuChina Research Institute of Petroleum Exploration and Development CNPCBeijing100083China Beijing Vocational College of Labour and Social Security Beijing100029China PetroChina Dagang Oilfield Exploration and Development Research Institute CNPCTianjin300280China

Knowledge about the seismic elastic modulus dispersion,and associated attenuation,in fluid-saturated rocks is essential for better interpretation of seismic observations taken as part of hydrocarbon identification and time-lapse seismic surveillance of both conventional and unconventional reservoir and overburden performances.A Seismic Elastic Moduli Module has been developed,based on the forced-oscillations method,to experimentally investigate the frequency dependence of Young's modulus and Poisson's ratio,as well as the inferred attenuation,of cylindrical samples under different confining pressure *** with three standard samples showed that the measured elastic moduli were consistent with the published data,indicating that the new apparatus can operate reliably over a wide frequency range of f∈[1-2000,10^(6)]*** Young's modulus and Poisson's ratio of the shale and the tight sandstone samples were measured under axial stress oscillations to assess the frequency-and pressure-dependent *** dry condition,both samples appear to be nearly frequency independent,with weak pressure dependence for the shale and significant pressure dependence for the *** particular,it was found that the tight sandstone with complex pore microstructure exhibited apparent dispersion and attenuation under brine or glycerin saturation conditions,the levels of which were strongly influenced by the increased effective *** addition,the measured Young's moduli results were compared with the theoretical predictions from a scaled poroelastic model with a reasonably good agreement,revealing that the combined fluid flow mechanisms at both mesoscopic and microscopic scales possibly responsible for the measured dispersion.

关键词： Low-frequency measurements Dispersion and attenuation Rock physics Fluid flow

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基于非线性定向降维的k近邻致密砂岩储层含气性预测方法

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Applied Geophysics 2024年第2期21卷 221-231,418页

作者：宋朝辉桑文镜袁三一王尚旭中国石油大学(北京) 地球物理学院北京102249

本文提出利用全连接人工神经网络(FANN)进行非线性定向降维并结合k近邻方法分类的致密砂岩储层含气性预测方法。k近邻方法能够依据样本间相似性,针对性地选取对应的部分训练样本建立局部模型,但缺乏含气敏感属性的提取能力,并面临“维... 详细信息

本文提出利用全连接人工神经网络(FANN)进行非线性定向降维并结合k近邻方法分类的致密砂岩储层含气性预测方法。k近邻方法能够依据样本间相似性,针对性地选取对应的部分训练样本建立局部模型,但缺乏含气敏感属性的提取能力,并面临“维度灾难”问题。由于样本中的含气性特征虽然是重要特征,但不一定是主要特征。线性降维方法难以准确提取这些特征。我们通过训练一个合理搭建的FANN并输出其中间低维特征实现对训练样本和待预测样本的非线性定向降维。这种做法既能够增加样本的可分性,同时避免了通过样本低维空间中的最大差异实现降维而改变样本固有分布特征的问题。另外,k近邻方法对降维数据进行分类,还等效于用k近邻方法替代FANN中具有线性分类作用的深层结构,有利于白化FANN的黑箱问题。本方法在具体的物理场景中挖掘机器学习算法的物理内涵,提高了智能方法的可解释性。将本方法应用在实际数据中,预测结果显示本方法能够一定程度上挖掘局部波形属性中蕴含的含气敏感信息,实现小范围的致密砂岩储层精确刻画。

关键词： k近邻方法致密砂岩储层预测非线性定向降维可解释性

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A novel texture clustering method based on shift invariant DWT and locality preserving projection

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第2期10卷 247-252页

作者： Rui XING san-yuan ZHANG Le-qing ZHU School of Computer Science and Technology Zhejiang University Hangzhou 310027 China

We propose a novel texture clustering method. A classical type of(approximate) shift invariant discrete wavelet transform(DWT),dual tree DWT,is used to decompose texture images. Multiple signatures are generated from the obtained high-frequency bands. A locality preserving approach is applied subsequently to project data from high-dimensional space to low-dimensional space. Shift invariant DWT can represent image texture information efficiently in combination with a histogram signature,and the local geometrical structure of the dataset is preserved well during clustering. Experimental results show that the proposed method remarkably outperforms traditional ones.

关键词： Shift invariant DWT. Texture signature Local preserving clustering Dimension reduction k-means

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构筑未来:框架化学的研究前沿与产业化展望

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中国科学：化学 2024年第6期54卷 815-821页

作者：岳衎丁三元雷浩卜显和陈小明付雪峰国家自然科学基金委员会化学科学部北京100085 华南理工大学前沿软物质学院广州510640 兰州大学功能有机分子化学国家重点实验室化学化工学院兰州730000 暨南大学广东省功能配位超分子材料及应用重点实验室化学与材料学院广州510632 南开大学材料科学与工程学院天津300350 中山大学化学学院广州510275

基于“框架化学的基础及应用研究”研讨会,本文阐述了“框架化学”的科学内涵,从框架结构的设计合成、精确表征、高性能化和产业应用四个方面综述了框架化学领域的主要研究进展,凝练了该领域的关键科学问题,并提出了面向国家需求和产业... 详细信息

基于“框架化学的基础及应用研究”研讨会,本文阐述了“框架化学”的科学内涵,从框架结构的设计合成、精确表征、高性能化和产业应用四个方面综述了框架化学领域的主要研究进展,凝练了该领域的关键科学问题,并提出了面向国家需求和产业发展的重点发展方向.

关键词：框架化学多孔材料金属-有机框架共价有机框架超分子有机框架

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Implementing VLPR systems based on TMS320DM642

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 2005-2016页

作者： ZHU Le-qing ZHANG san-yuan YE Xiu-zi School of Computer Science and Technology Zhejiang University Hangzhou 310027 China

This paper gives a practical schema for using DSP boards to construct Vehicle License Plate Recognition (VLPR) modules that could be embedded in any Intelligent Transportation System (ITS). Using DSP can avoid the heavy investment in dedicated VLPR system and improve the computational power compared to PC software environment. Low cost, high computational power, and high flexibility of DSP provide the License Plate Recognition System (LPRS) an excellent cost-effective solution to execute the major part of the recognition tasks. This paper describes a successful implementation of VLPR system based on Texas Instruments (TI)'s TMS320DM642. The DSP board acquires video (which could be output to a monitor for surveillance) from a camera, captures images from the video, locates and recognizes the license plates in images, and then sends the recognized results and related images after compression to a host PC through the network. Finally, the overall software is optimized according to the features of DM642 chip. Experiments showed that the DSP VLPR system performs well on the local license plates, and that the processing speed and accuracy can meet the requirement of practical applications.

关键词： License Plate Recognition (LPR) Embedded system Image processing DSP DM642

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Genome editing in Bombyx mori: New opportunities for silkworm functional genomics and the sericulture industry

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Insect Science 2019年第6期26卷 964-972页

作者： san-yuan Ma Guy Smagghe Qing-You Xia State Key Laboratory of Silkworm Genome Biology Southwest University ChongqingChina Chongqing Engineering and Technology Research Center for Novel Silk Materials Southwest University Chongqing China Department of Crop Protection Faculty of Bioscience Engineering Ghent University Ghent Belgium

In recent years, research in life sciences has been remarkably revolutionized owing to the establishment, development and application of genome editing technologies. Genome editing has not only accelerated fundamental research but has also shown promising applications in agricultural breeding and therapy. In particular, the clustered, regularly interspaced, short palindromic repeat (CRISPR) technology has become an indispensable tool in molecular biology owing to its high efficacy and simplicity. Genome editing tools have also been established in silkworm (Bombyx mori), a model organism of Lepidoptera insects with high economic importance. This has remarkably improved the level and scope of silkworm research and could reveal new mechanisms or targets in basic entomology and pest management studies. In this review, we summarize the progress and potential of genome editing in silkworm and its applications in functional genomic studies for generating novel genetic materials.

关键词： CRISPR genome editing silkworm TALEN ZFN

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