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PD-YOLO:Colon Polyp Detection Model Based on Enhanced Small-Target Feature Extraction

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Computers, Materials & Continua 2025年第1期82卷 913-928页

作者： Yicong Yu Kaixin lin Jiajun Hong rong-Guei Tsai Yuanzhi Huang New Engineering Industry College Putian UniversityPutian351100China Engineering Research Center of Big Data Application in Private Health Medicine(Putian University) Fujian Province UniversityPutian351100China Computer College Guangdong University of Science&TechnologyDongguan523668China

In recent years,the number of patientswith colon disease has increased *** polyps are the precursor lesions of colon *** not diagnosed in time,they can easily develop into colon cancer,posing a serious threat to patients’lives and health.A colonoscopy is an important means of detecting colon ***,in polyp imaging,due to the large differences and diverse types of polyps in size,shape,color,etc.,traditional detection methods face the problem of high false positive rates,which creates problems for doctors during the diagnosis *** order to improve the accuracy and efficiency of colon polyp detection,this question proposes a network model suitable for colon polyp detection(PD-YOLO).This method introduces the self-attention mechanism CBAM(Convolutional Block Attention Module)in the backbone layer based on YOLOv7,allowing themodel to adaptively focus on key information and ignore the unimportant *** help themodel do a better job of polyp localization and bounding box regression,add the SPD-Conv(Symmetric Positive Definite Convolution)module to the neck layer and use deconvolution instead of *** results indicate that the PD-YOLO algorithm demonstrates strong robustness in colon polyp *** to the original YOLOv7,on the Kvasir-SEG dataset,PD-YOLO has shown an increase of 5.44 percentage points in AP@0.5,showcasing significant advantages over other mainstream methods.

关键词： Polyp detection YOLOv7 SPD-Conv CBAM deconvolution

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溯因推理研究:现状与问题

计算机科学 2003年第5期30卷 23-25,36页

作者：陈荣姜云飞林笠中山大学软件所广州510275 暨南大学数学系广州510632

The notion of abduction was first introduced by the philosopher and logician C. S. Pierce, who claims de-duction, abduction and induction are three different forms of human reasoning. Broadly speaking, abduction is a rea-soning process invoked to explain a puzzling observation. The study of logic-based abduction has been the most activeresearch in AI, and there are many results around the subject. This paper surveys the state-of-the-art research andpresents some problems for future work.

关键词：人工智能溯因推理归纳推理演绎推理

Mesopolymer modified with palladium phthalocyaninesulfonate as a versatile photocatalyst for phenol and bisphenol A degradation under visible light irradiation

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Journal of Environmental Sciences 2013年第8期25卷 1687-1695页

作者： rong Xing lin Wu Zhenghao fei Peng Wu Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection Yancheng Teachers University Yancheng 224002 China Shanghai Key Laboratory of Green Chemistry and Chemical Processes Department of Chemistry East China Normal University Shanghai 200062 China

A novel versatile photocatalyst, FDU-PdPcS, was prepared by immobilizing palladium phthalocyaninesulfonate （PdPcS） onto the FDU-15 mesopolymer via multi-step chemical modification processes involving chloromethylation of the FDU-15 mesopolymer first with chloromethyl methyl ether, a subsequent amination reaction with ethylenediamine, and finally modification with palladium phthalocyaninesulfonate via ionic interaction. The obtained FDU-PdPcS photocatalyst was characterized by the X-ray diffraction （XRD）, UV-Vis spectrosopy and inductively coupled plasma （ICP） techniques. This photocatalyst not only affords a high dispersion of monomeric PdPcS molecules, which may further be stabilized by the π-electron of benzene rings of FDU-15, but also provides a number of diamino groups inside the mesopores, which could be advantageous for the photodegradation of phenolic pollutants. In photodegradation studies of phenolic pollutants, the FDU-PdPcS catalyst exhibited excellent visible light photocatalytic activity and reusability. The photodegradation products of phenol and bisphenol A were investigated by the gas chromatoghraphy-mass spectrometry （GC-MS） technique. The results showed that the photodegradation products were composed of carboxylic acids and CO2. Isopropanol, sodium azide and benzoquinone were used as hydroxyl radical （OH.）, singlet oxygen （1O2） and superoxide radical （O2.-） scavengers, respectively. The results suggested that 1O2 and O2. were the prominent active species during the photodegradation process. A possible mechanism for the photodegradation of phenol was also discussed.

关键词： mesopolymer phthalocyanine photocatalysis visible light phenolic pollutants

Pseudopotential Density-Functional Calculations for Structures of Small CarbonClusters CN （N=2-8）

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Communications in Theoretical Physics 2004年第1期41卷 89-94页

作者： BAIYu-lin CHENXiang-rong YANGXiang-Dong LUPeng-fei lnstituteofAtomicandMolecularPhysics SichuanUniversityChengdu610065ChinaDepartmentofElectronicInformationScienceandTechnologyYibinUniversityYibin644000China lnstituteofAtomicandMolecularPhysics SichuanUniversityChengdu610065China

We introduce a first-principles density-functional theory,*** finite-difference pseudopotential density- functional theory in real space and the Langevin molecular dynamics annealing technique,to the descriptions of structures and some properties of small carbon clusters(C_N,N=2～8).It is shown that the odd-numbered clusters have linear structures and most of the even-numbered clusters prefer cyclic structures.

关键词： pseudopotential density-functional theory real space Langevin molecular dynamics annealing technique small carbon clusters

粉质黏土和风化粉砂岩中变径抗浮锚杆高效绿色成孔关键技术

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山西建筑 2025年第1期51卷 80-83,133页

作者：林飞江苏省新能源地质调查大队江苏南京210041 江苏华东建设基础工程有限公司江苏南京210007

为了提高粉质黏土和全风化、强风化粉砂岩地层中变径抗浮锚杆的成孔工效,对长螺旋钻机进行了改进,使其具有送风功能,开发了长螺旋钻机引孔接力高压旋喷钻机扩孔下变径抗浮锚杆成孔关键技术,并提出了相应的施工参数。采用关键技术和施工... 详细信息

为了提高粉质黏土和全风化、强风化粉砂岩地层中变径抗浮锚杆的成孔工效,对长螺旋钻机进行了改进,使其具有送风功能,开发了长螺旋钻机引孔接力高压旋喷钻机扩孔下变径抗浮锚杆成孔关键技术,并提出了相应的施工参数。采用关键技术和施工参数,保证变径抗浮锚杆抗拔力达到设计要求外,与单一高压旋喷钻机进行变径抗浮锚杆成孔的常规工艺相比,减少了13%的工期。鉴于粉质黏土和全风化、强风化粉砂岩地层中,高压送风长螺旋钻机引孔时会产生扬尘,开发了配套的降尘结构,消除了扬尘引起的环境问题及对作业人员的危害,实现了绿色施工。

关键词：变径抗浮锚杆粉质黏土长螺旋钻机引孔扩孔

Influence of matrix physical properties on flow characteristics in dual network model

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Petroleum Science 2023年第4期20卷 2244-2252页

作者： Chen-Chen Wang Yong-fei Yang Deng-lin Han Miao-Miao Su rong-rong Hu Cooperative Innovation Center of Unconventional Oil and Gas Yangtze UniversityWuhan430100HubeiChina Laboratory of Reservoir Microstructure Evolution and Digital Characterization Yangtze UniversityWuhan430100HubeiChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina School of Geosciences Yangtze UniversityWuhan430100HubeiChina College of Resources and Environment Yangtze UniversityWuhan430100HubeiChina School of Petroleum Engineering Yangtze UniversityWuhan430100HubeiChina

The tight oil formation develops with microfractures and matrix pores,it is important to study the influence of matrix physical properties on flow *** first,the representative fracture and matrix samples are selected respectively in the dual media,the fracture and matrix digital rocks are constructed with micro-CT scanning at different resolutions,and the corresponding fracture and matrix pore networks are extracted,***,the modified integration method is proposed to build the dual network model containing both fracture and matrix pore-throat elements,while the geometric-topological structure equivalent matrix pores are generated to fill in the skeleton domain of fracture network,the constructed dual network could describe the geometric-topological structure characteristics of fracture and matrix pore-throat *** last,by adjusting the matrix pore density and the matrix filling domain factor,a series of dual network models are obtained to analyze the influence of matrix physical properties on flow characteristics in *** can be seen that the matrix system contributes more to the porosity of the dual media and less to the *** the decrease in matrix pore density,the porosity/permeability contributions of matrix system to dual media keep decreasing,but the decrease is not significant,the oil-water co-flow zone decreases and the irreducible water saturation increases,and the saturation interval dominated by the fluid flow in the fracture keeps *** the decrease in matrix filling domain factor,the porosity/permeability contributions of matrix system to dual media decreases,the oil-water co-flow zone increases and the irreducible water saturation decreases,and the saturation interval dominated by the fluid flow in the fracture keeps *** results can be used to explain the dual-media flow pattern under different matrix types and different fracture control volumes during tight oil production

关键词： Network integration Dual media Flow characteristics Matrix pore density Matrix filling domain

On the Optimal Initial Inner-Core Size for Tropical Cyclone Intensification: An Idealized Numerical Study

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Advances in Atmospheric Sciences 2024年第11期41卷 2141-2155页

作者： rong fei Yuqing WANG School of Atmospheric Sciences and Remote Sensing Wuxi UniversityWuxi 214105China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China International Pacific Research Center Department of Atmospheric SciencesSchool of Ocean and Earth Science and TechnologyUniversity of Hawaii at ManoaHonoluluHawaii 96822USA

Recent observational and numerical studies have revealed the dependence of the intensification rate on the inner-core size of tropical cyclones(TCs). In this study, with the initial inner-core size(i.e., the radius of maximum wind—RMW)varied from 20–180 km in idealized simulations using two different numerical models, we found a nonmonotonic dependence of the lifetime maximum intensification rate(LMIR) on the inner-core size. Namely, there is an optimal innercore size for the LMIR of a TC. Tangential wind budget analysis shows that, compared to large TCs, small TCs have large inward flux of absolute vorticity due to large absolute vorticity inside the RMW. However, small TCs also suffer from strong lateral diffusion across the eyewall, which partly offsets the positive contribution from large inward flux of absolute vorticity. These two competing processes ultimately lead to the TC with an intermediate initial inner-core size having the largest LMIR. Results from sensitivity experiments show that the optimal size varies in the range of 40–120 km and increases with higher sea surface temperature, lower latitude, larger horizontal mixing length, and weaker initial TC intensity. The 40–120 km RMW corresponds to the inner-core size most commonly found for intensifying TCs in observations, suggesting the natural selection of initial TC size for intensification. This study highlights the importance of accurate representation of TC inner-core size to TC intensity forecasts by numerical weather prediction models.

关键词： tropical cyclones intensification inner-core size idealized simulations

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予条件共轭梯度法的收敛性

计算物理 1986年第4期 487-495页

作者：胡家赣王邦荣陈创飞刘兴平应用物理与计算数学研究所应用物理与计算数学研究所北京

本文对某些予条件共轭梯度法的收敛性进行了一些分析,如ICCG法,ILUCK(K)法、ILUCG(P)法及所谓的“TCG法”,其中用了许多分裂作为对所要解的线性代数方程组的系数矩阵A进行予条件的工具,这里设A为对角优势矩阵,文中还给出了若干数值算例... 详细信息

本文对某些予条件共轭梯度法的收敛性进行了一些分析,如ICCG法,ILUCK(K)法、ILUCG(P)法及所谓的“TCG法”,其中用了许多分裂作为对所要解的线性代数方程组的系数矩阵A进行予条件的工具,这里设A为对角优势矩阵,文中还给出了若干数值算例来说明我们分析的结果。

关键词：收敛性分裂法计算方法系数矩阵共轭梯度法

Synthetic analysis of a two-ribbon microflare

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Research in Astronomy and Astrophysics 2010年第1期10卷 83-90页

作者： Cheng Fang Peng-fei Chen rong-lin Jiang Yu-Hua Tang Department of Astronomy Nanjing University Nanjing 210093 China

High-resolution Stokes spectral data of Hα, Ca Ⅱ 8542A, and Fe 16302.5A lines for a two-ribbon microflare （TRMF） were simultaneously obtained by the THEMIS telescope on 2002 September 5. We derive the intensity, velocity, and longitudinal magnetic field maps. The hard X-ray emission observed by RHESSI provides evidence of nonthermal particle acceleration in the TRMF. Using Ha and Ca Ⅱ 8542A line profiles and a non-LTE calculation, we obtain semi-empirical atmospheric models for the two brightest kernels of the TRME Our result indicates that the temperature enhancement in the chromosphere is more than 2500 K. The kinetic and radiative energies at the kernels are also estimated, resulting in an estimate of the total energy of the TRMF of about 2.4×10^29 erg. Observations indicate that the TRMF results from the low coronal magnetic reconnection following the eruption of a small fila- ment. However, the local temperature ＂bump＂ in the chromosphere presents a puzzle for such a standard flare model. A possible solution to this is discussed.

关键词： Sun chromosphere- Sun flares - Sun activity - Sun magnetic fields