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Chinese Medical Journal 2024年第9期137卷 1124-1126页

作者： Hui Li zuoqiang liu Linli Jiang Jiangyu Liang Lei liu Department of Oral and Maxillofacial Surgery State Key Laboratory of Oral Disease&National Center for Stomatology&National Clinical Research Center for Oral DiseasesWest China Hospital of StomatologySichuan UniversityChengduSichuan 610041China Department of Biomaterials Sciences and Prosthodontics School of DentistryUniversity of MichiganAnn ArborMIUnited States

To the Editor:The jaw cyst is one of the most common benign tumors in the oral and maxillofacial region.[1]To date,several studies have reported on jaw cysts in general populations from Italy,Brazil,Greece,and the United States in accordance with the 4th World Health Organization(WHO)classication of head and neck tumors.[2]However,there are no clinicopathological studies of odontogenic and non-odontogenic cysts in a large Chinese population in relation to the latest WHO classi***,few epidemiological studies have analyzed treatment plans and the possible postoperative complications of jaw ***,this study aimed to perform a detailed and extended epidemiological analysis of jaw cysts in a large population in West China.

关键词： clinic treatment pathologic

玛湖凹陷三叠系百口泉组地层再认识与勘探潜力分析

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特种油气藏 2024年第2期31卷 28-36页

作者：钟厚财朱俊梅林煜邓勇刘作强黄友华张珊屈琳中国石油东方地球物理勘探有限责任公司河北涿州072750

为进一步探索玛中平台区近4000.0 km 2勘探空白区的勘探潜力,扩大玛湖凹陷百口泉组勘探潜力,实现玛湖凹陷整体突破,综合利用地质、钻井、高精度地震等资料,对玛湖凹陷百口泉组地层划分进行了细化,将玛中平台区低位域砂体划分为百口泉组... 详细信息

为进一步探索玛中平台区近4000.0 km 2勘探空白区的勘探潜力,扩大玛湖凹陷百口泉组勘探潜力,实现玛湖凹陷整体突破,综合利用地质、钻井、高精度地震等资料,对玛湖凹陷百口泉组地层划分进行了细化,将玛中平台区低位域砂体划分为百口泉组零段(百零段)。在此基础上,结合区域沉积、构造背景,从烃源岩条件、疏导体系、沉积体系和成藏条件等方面对玛中平台区低位域百零段油气成藏条件及控制因素展开了综合分析。研究表明:二叠系风城组烃源岩具有碱湖双峰式生油特征,油气资源基础大,百零段更近源,更容易捕获深层油气;玛中平台区印支期走滑断裂直插深层烃源岩,搭接形成了高效的输导体系;百口泉组顶底板条件优越,百零段在大型地层超覆背景下叠置发育多期湖侵退积砂体,形成规模有效的储盖组合;百零段发育四大规模扇体,其扇三角洲平原亚相致密带、扇间泥岩、构造等值线相互配置,形成复合式多面遮挡,为扇三角洲前缘大面积成藏奠定了基础。类比研究认为,中拐扇前缘亚相上倾、侧向遮挡条件好,具有宏观整体成藏基础。该区前缘亚相有利勘探面积大,岩性目标叠置发育,落实程度高,是目前寻求百零段新层系突破的重点勘探目标。百零段的突破有望打开玛中平台区勘探局面,进而实现玛湖凹陷百口泉组整体突破。

关键词：扇控大面积成藏低位域勘探潜力分析百口泉组玛中平台区玛湖凹陷

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NSNO:Neumann Series Neural Operator for Solving Helmholtz Equations in Inhomogeneous Medium

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Journal of Systems Science & Complexity 2024年第2期37卷 413-440页

作者： CHEN Fukai liu Ziyang LIN Guochang CHEN Junqing SHI zuoqiang Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China Yau Mathematical Sciences Center Tsinghua UniversityBeijing 100084China Yanqi Lake Beijing Institute of Mathematical Sciences and Applications Beijing 101408China

In this paper,the authors propose Neumann series neural operator(NSNO)to learn the solution operator of Helmholtz equation from inhomogeneity coefficients and source terms to *** equation is a crucial partial differential equation(PDE)with applications in various scientific and engineering ***,efficient solver of Helmholtz equation is still a big challenge especially in the case of high ***,deep learning has shown great potential in solving PDEs especially in learning solution *** by Neumann series in Helmholtz equation,the authors design a novel network architecture in which U-Net is embedded inside to capture the multiscale *** experiments show that the proposed NSNO significantly outperforms the state-of-the-art FNO with at least 60%lower relative L^(2)-error,especially in the large wavenumber case,and has 50%lower computational cost and less data ***,NSNO can be used as the surrogate model in inverse scattering *** tests show that NSNO is able to give comparable results with traditional finite difference forward solver while the computational cost is reduced tremendously.

关键词： Helmholtz equation inverse problem neumann series neural network solution operator

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电动汽车高压配电盒热仿真分析

汽车电器 2024年第1期 1-6页

作者：刘作强李智聂金泉王长福安炯湖北文理学院汽车与交通工程学院湖北襄阳441053 襄阳群龙汽车部件股份有限公司湖北襄阳441199

高压配电盒在工作过程中会产生热量,为探究高压配电盒的工作温升是否满足设计要求,文章以某型号的高压配电盒为研究对象,采用有限元方法建立高压配电盒的三维模型,并利用ANSYS Icepak软件进行仿真,分析两种不同条件下高压配电盒的温度... 详细信息

高压配电盒在工作过程中会产生热量,为探究高压配电盒的工作温升是否满足设计要求,文章以某型号的高压配电盒为研究对象,采用有限元方法建立高压配电盒的三维模型,并利用ANSYS Icepak软件进行仿真,分析两种不同条件下高压配电盒的温度分布。仿真结果表明:在两种不同条件下,高压配电盒主要元器件的工作温升都在合理范围之内,能够满足设计要求。

关键词：电动汽车高压配电盒热仿真 ANSYS Icepak

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基于快速傅里叶变换的四种相位解包裹算法

强激光与粒子束 2013年第5期4卷 1129-1133页

作者：王华英于梦杰刘飞飞刘佐强河北工程大学信息与电气工程学院河北邯郸056038 河北工程大学理学院河北邯郸056038

为了快速准确地对含有噪声的包裹相位图进行相位展开,采用理论分析与计算机模拟及实验验证相结合的方法,对基于快速傅里叶变换(FFT)的四种典型算法——四次FFT算法(4-FFT)、二次FFT算法(2-FFT)、四次离散余弦变换算法(4-DCT)及横向剪切... 详细信息

为了快速准确地对含有噪声的包裹相位图进行相位展开,采用理论分析与计算机模拟及实验验证相结合的方法,对基于快速傅里叶变换(FFT)的四种典型算法——四次FFT算法(4-FFT)、二次FFT算法(2-FFT)、四次离散余弦变换算法(4-DCT)及横向剪切干涉与FFT相结合的算法(LS-FFT)作了对比研究。结果表明:2-FFT算法运行速度最快,4-FFT算法次之,LS-FFT算法速度最慢;4-FFT算法对含有较强噪声和轻微欠采样的实验数据的处理效果是最好的;LS-FFT算法对强噪声数据的处理效果最差。

关键词：相位解包裹快速傅里叶变换离散余弦变换噪声欠采样

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预放大数字全息显微系统的特性分析

强激光与粒子束 2013年第6期25卷 1365-1369页

作者：王华英刘飞飞宋修法廖薇于梦杰刘佐强马彦晓河北工程大学理学院河北邯郸056038 河北工程大学信息与电子工程学院河北邯郸056038

为了提高预放大数字全息显微系统的成像质量,采用理论分析与实验验证相结合的方法,分别对采用平面及球面参考光记录的预放大数字全息显微系统进行了研究和比较。结果表明:在通常的实验条件下,系统的横向分辨力主要取决于显微物镜的成像... 详细信息

为了提高预放大数字全息显微系统的成像质量,采用理论分析与实验验证相结合的方法,分别对采用平面及球面参考光记录的预放大数字全息显微系统进行了研究和比较。结果表明:在通常的实验条件下,系统的横向分辨力主要取决于显微物镜的成像分辨力;记录距离较小时,两种系统的横向分辨力均随着记录距离的增大略有降低;但当记录距离较大时,球面参考光预放大数字全息系统的横向分辨力降低得更为明显,即平面参考光预放大数字全息显微系统较为优越;在记录距离为0的情况下,即像面数字全息成像情况下,两种系统的再现像均具有最高的分辨力,在利用普通工业用传感器条件下,横向分辨力远超过了2.19μm,且像质较好。因此,尽可能减小全息图的记录距离,或者采用像面数字全息系统,可以有效提高数字全息系统的成像分辨力。

关键词：预放大数字全息术平面参考光球面参考光点扩散函数横向分辨力

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水温对透水沥青混合料力学性能的影响

重庆理工大学学报（自然科学） 2022年第5期36卷 115-121页

作者：张海涛郭志超刘作强东北林业大学土木工程学院哈尔滨150040

为研究水温作用对透水沥青混合料力学性能的影响,采用试验评价与细观图像处理技术,对不同水温状态下的沥青混合料力学性能与细观结构展开分析。研究内容包括:沥青混合料配合比设计,劈裂试验与冻融循环劈裂试验,浸水马歇尔试验,不同水温... 详细信息

为研究水温作用对透水沥青混合料力学性能的影响,采用试验评价与细观图像处理技术,对不同水温状态下的沥青混合料力学性能与细观结构展开分析。研究内容包括:沥青混合料配合比设计,劈裂试验与冻融循环劈裂试验,浸水马歇尔试验,不同水温状态下试件断面细观结构分析。研究表明:水温作用对沥青混合料力学性能有一定程度上的损伤,并且沥青混合料的力学性能与水温作用时间以及温度呈线性负相关。此外,水温对大孔隙透水沥青混合料效果更明显,而使用高粘沥青会改善沥青混合料的水温稳定性。研究成果可为解决透水沥青混合料在实际工程中的水温稳定性问题提供参考。

关键词：透水沥青混合料水温力学性能数字图像处理细观结构

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球面参考光预放大数字全息成像系统分辨力

强激光与粒子束 2013年第2期25卷 345-349页

作者：王华英刘飞飞成惠廖薇赵宝群于梦杰刘佐强河北工程大学理学院河北邯郸056038 河北工程大学信息与电气工程学院河北邯郸056038

为了提高数字全息成像系统的成像分辨力,对以球面波作为参考光波的预放大数字全息成像系统的记录和再现过程进行了理论推导,得出了该系统的脉冲响应表达式,并由此分析了决定该系统成像分辨力的因素。在CCD成像分辨力高于显微物镜分辨力... 详细信息

为了提高数字全息成像系统的成像分辨力,对以球面波作为参考光波的预放大数字全息成像系统的记录和再现过程进行了理论推导,得出了该系统的脉冲响应表达式,并由此分析了决定该系统成像分辨力的因素。在CCD成像分辨力高于显微物镜分辨力的情况下,通过对分辨力测试板进行实验,讨论了系统分辨力与记录距离的关系。结果表明:再现像的分辨力对记录距离不敏感;但在记录距离为零,即像面数字全息系统下,再现像具有更高的分辨力。实验结果与理论分析一致。

关键词：预放大数字全息像面数字全息球面参考光脉冲响应分辨力

Frequency Regulation of VSC-MTDC System with Offshore Wind Farms

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 275-286页

作者： Haoyu liu Chongru liu North China Electric Power University Beijing 102206China

Frequency regulation of voltage source converter-based multi-terminal high-voltage direct current(VSC-MTDC)system with offshore wind farms enhances the frequency stability by compensating the power for a disturbed AC ***,it is difficult to reasonably allocate frequency-regulation resources due to a lack of coordination mechanisms between wind farms and the MTDC ***,it is difficult for the frequency control of the wind farms to manage changes in wind speed;and the risk of wind-turbine stalls is ***,based on the kinetic energy of wind turbines and the power margin of the converters,the frequency-regulation capability of wind turbines is evaluated,and a dynamic frequency-support scheme considering the real-time frequency-support capability of the wind turbines and system frequency evolution is proposed to improve the frequency-support performance.A power adaptation technique at variable wind speeds is developed;the active power in the frequency-support stage and restoration stage is switched according to the wind speed.A hierarchical zoning frequency-regulation scheme is designed to use the frequency-regulation resources of different links in the MTDC system with wind *** simulation results show that the novel frequency-regulation strategy maintains frequency stability with wind-speed changes and avoids multiple frequency dips.

关键词： Wind generation voltage source converter-based multi-terminal high-voltage direct current(VSC-MTDC) frequency regulation cooperative control adaptive control variable wind speed

A Novel Design of a Pre-separation Panel Structure to Protect Against the Impact of an Explosion in an Aircraft Plenum Chamber

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Acta Mechanica Solida Sinica 2024年第1期37卷 166-180页

作者： Zongxing liu Xiang Yang Jun liu School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China COMAC Shanghai Aircraft Design and Research Institute Shanghai 201210China

To reduce the damage of the pressurizing panel structure of a fuselage caused by an explosion at the“least risk bomb location”in an aircraft structure,a new pre-separation panel structure was designed to resist blast ***,the dynamic strain response and morphology of impact damage of the new pre-separation panel were measured in an impact damage ***,the commercial software LS-DYNA was used to calculate the propagation of the blast shock wave,and the results were compared with empirical equations to verify the rationality of the numerical calculation ***,the fluid–structure coupling method was used to calculate the damage process of the pre-separation panel structure under the impact of an explosion wave and an impact *** calculated results were in good agreement with the test results,which showed the rationality of the calculation method and the *** residual strength of the damaged pre-separation panel was significantly higher than that of the original damaged *** results show that the new pre-separation panel structure is reasonable and has certain significance for guiding the design of plenum chambers with strong resistance to implosion for aircraft fuselages.

关键词： Pre-separation panel structure Explosive response Residual strength Aircraft plenum chamber Least risk bomb location