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农业信息处理(英文) 2023年第2期10卷 149-163页

作者： Yang Zhang Jun Yue Aihuan song shixiang Jia Zhenbo Li School of Information and Electrical Engineering Ludong UniversityYantai 264025PR China Marine Biology Institute of Shandong Province Qingdao 266104PR China School of Information and Electrical Engineering China Agricultural UniversityBeijing 100193PR China

The high similarity of shellfish images and unbalanced samples are key factors affecting the accuracy of shellfish *** study proposes a new shellfish recognition method FL_Net based on a Convolutional Neural Network(CNN).We first establish the shellfish image(SI)dataset with 68 species and 93574 images,and then propose a filter pruning and repairing model driven by an output entropy and orthogonality measurement for the recognition of shellfish with high similarity features to improve the feature expression ability of valid *** the shellfish recognition with unbalanced samples,a hybrid loss function,including regularization term and focus loss term,is employed to reduce the weight of easily classified samples by controlling the shared weight of each sample species to the total *** experimental results show that the accuracy of shell-fish recognition of the proposed method is 93.95%,13.68%higher than the benchmark network(VGG16),and the accuracy of shellfish recognition is improved by 0.46%,17.41%,17.36%,4.46%,1.67%,and 1.03%respectively compared with AlexNet,GoogLeNet,ResNet50,SN_Net,MutualNet,and ResNeSt,which are used to verify the efficiency of the proposed method.

关键词： Shellfish recognition High similarity Unbalanced samples Convolutional Neural Network Filter pruning and repairing Hybrid loss function

Differences in the Tectonic Evolution of Basins in the CentralSouthern South China Sea and their Hydrocarbon Accumulation Conditions

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Acta Geologica Sinica(English Edition) 2021年第1期95卷 30-40页

作者： TANG Wu ZHAO Zhigang song Shuang WANG Yibo XIE Xiaojun LIU shixiang CNOOC Research Institute Co. Ltd.Beijing 100028China

To reveal the causes of differences in the hydrocarbon accumulation in continental marginal basins in the centralsouthern South China Sea,we used gravity-magnetic,seismic,drilling,and outcrop data to investigate the tectonic histories of the basins and explore how these tectonic events controlled the hydrocarbon accumulation conditions in these *** the subduction of the Cenozoic proto-South China Sea and the expansion of the new South China Sea,the continental margin basins in the central-southern South China Sea could be classified as one of three types of epicontinental basins:southern extensional-foreland basins,western extensional-strike slip basins,and central extensional-drift *** these basins have different tectonic and sedimentary histories,they also differ in their accumulated hydrocarbon *** the Cenozoic,the basin groups in the southern South China Sea generally progressed through three stages:faulting and subsidence from the late Eocene to the early Miocene,inversion and uplift in the middle Miocene,and subsidence since the late *** source rocks with marine-continental transitional facies dominated byⅡ-Ⅲkerogen largely developed in extremely thick Miocene sedimentary series with the filling characteristics being mainly deep-water deposits in the early stage and shallow water deposits in the late *** well-developed sandstone and carbonate reservoirs,this stratum has a strong hydrocarbon generation *** the Cenozoic,the basin groups in the western South China Sea also progressed through the three developmental stages discussed *** source rocks with lacustrine facies,marine-continental transitional facies,and terrigenous marine facies dominated byⅡ2-Ⅲkerogen largely developed in the relatively thick stratum with the filling characteristics being mainly lacustrine deposits in the early stage and marine deposits in the late *** a reservoir comprised of self-generated a

关键词： tectonic evolution hydrocarbon accumulation continental margin central-southern South China Sea proto-South China Sea

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基于雷-菲法的油气管道可靠性分析

辽宁石油化工大学学报 2013年第2期33卷 39-42页

作者：宋士祥吴明刘珂张国军马跃范开锋辽宁石油化工大学石油天然气工程学院辽宁抚顺113001 沈阳特种设备检测研究院辽宁沈阳110036

影响管道安全可靠性的因素众多且具有随机性,因此直接求解极限状态方程比较困难。应用雷-菲法,求解过程简便且精度高。基于可靠性理论和B31G—1991标准,综合考虑腐蚀缺陷长度、径向缺陷深度、腐蚀速率、壁厚、管材屈服强度、管线内压等... 详细信息

影响管道安全可靠性的因素众多且具有随机性,因此直接求解极限状态方程比较困难。应用雷-菲法,求解过程简便且精度高。基于可靠性理论和B31G—1991标准,综合考虑腐蚀缺陷长度、径向缺陷深度、腐蚀速率、壁厚、管材屈服强度、管线内压等可靠性影响因素的随机性,应用雷-菲法建立腐蚀管道可靠性评价模型,编制了相应的计算程序。计算结果表明,缺陷深度是管道失效的主要影响因素;管道的可靠性指数随缺陷长度、缺陷深度、径向腐蚀速率的增加而降低,随着管材屈服强度的增加呈线性增加,随内压的增加迅速减小。

关键词：雷-菲法可靠性油气管道一次二阶矩法

The gradual subduction-collision evolution model of Proto-South China Sea and its control on oil and gas

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Acta Oceanologica Sinica 2023年第3期42卷 123-137页

作者： Xiaojun Xie Wu Tang Gongcheng Zhang Zhigang Zhao Shuang song shixiang Liu Yibo Wang Jia Guo China National Offshore Oil Corporation(CNOOC)Research Institute Co. Ltd.Beijing 100028China

This study involved outcrop,drilling,seismic,gravity,and magnetic data to systematically document the geological records of the subduction process of Proto-South China Sea(PSCS)and establish its evolution *** results indicate that a series of arc-shaped ophiolite belts and calcalkaline magmatic rocks are developed in northern Borneo,both of which have the characteristics of gradually changing younger from west to east,and are direct signs of subduction and collision of *** the same time,the subduction of PSCS led to the formation of three accretion zones from the south to the north in Borneo,the Kuching belt,Sibu belt,and Miri *** sedimentary formation of northern Borneo is characterized by a three-layer structure,with the oceanic basement at the bottom,overlying the deep-sea flysch deposits of the Rajang–Crocker group,and the molasse sedimentary sequence that is dominated by river-delta and shallow marine facies at the top,recording the whole subduction–collision–orogeny process of ***,seismic reflection and tomography also confirmed the subduction and collision of *** on the geological records of the subduction and collision of PSCS,combined with the comprehensive analysis of segmented expansion and key tectonic events in the South China Sea,we establish the“gradual”subduction-collision evolution model of *** the late Eocene to middle Miocene,the Zengmu,Nansha,and Liyue–Palawan blocks were separated by West Baram Line and Balabac Fault,which collided with the Borneo block and Kagayan Ridge successively from the west to the east,forming several foreland basin systems,and PSCS subducted and closed from the west to the *** subduction and extinction of PSCS controlled the oil and gas distribution pattern of southern South China Sea(SSCS)mainly in three ***,the“gradual”closure process of PSCS led to the continuous development of many large deltas in ***,the deltas formed during the subduction–collision of PS

关键词： Proto-South China Sea gradual subduction-collision evolution model oil and gas distribution southern South China Sea Borneo

Recent advances in generation of terahertz vortex beams andtheir applications

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Chinese Physics B 2020年第9期29卷 105-121页

作者： Honggeng Wang Qiying song Yi Cai Qinggang Lin Xiaowei Lu Huangcheng Shangguan Yuexia Ai shixiang Xu Shenzhen Key Laboratory of Micro-Nano Photonic Information Technology College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China Key Laboratory of Optoelectronic Devices and Systems and Ministry of Education and Guangdong Province College of Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

Last decade has witnessed a rapid development of the generation of terahertz(THz)vortex beams as well as their wide applications,mainly due to their unique combination characteristics of regular THz radiation and orbital angular momentum(OAM).Here we have reviewed the ways to generate THz vortex beams by two representative scenarios,i.e.,THz wavefront modulation via specific devices,and direct excitation of the helicity of THz vortex *** former is similar to those wavefront engineering devices in the optical and infrared(IR)domain,but just with suitable THz materials,while the latter is newly-developed in THz regime and some of the physical mechanisms still have not been explained explicitly enough though,which would provide both challenges and opportunities for THz vortex beam *** for their applications,thanks to the recent development of THz optics and singular optics,THz vortex beams have potentials to open doors towards a myriad of practice applications in many ***,some representative potential applications are evaluated such as THz wireless communication,THz super-resolution imaging,manipulating chiral matters,accelerating electron bunches,and detecting astrophysical sources.

关键词： terahertz vortex beams wavefront modulation orbital angular momentum nonlinear optics

PI-RADSv2.1联合PSAMR在tPSA<20ng/mL的前列腺癌诊断中的价值

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临床泌尿外科杂志 2024年第2期39卷 125-130页

作者：胡红跃卓栋张振兴宋周良汪小勇谈杰侯敬元江世祥铜陵市立医院泌尿外科安徽铜陵244000 皖南医学院弋矶山医院泌尿外科

目的:探索前列腺特异性抗原质量比(prostatespecific antigen mass ratio,PSAMR)在总前列腺特异性抗原(total prostate-specific antigen,tPSA)<20ng/mL的前列腺癌(prostate cancer,PCa)诊断中的价值。并结合2.1版前列腺影像报告与数据系统(prostate imagingr eporting and data system,PI-RADSv2.1)评分进一步建立预测PCa风险的预测模型。方法:回顾性分析2021年7月—2023年3月期间皖南医学院弋矶山医院收治的382例行MRITRUS融合靶向活检的可疑PCa患者的临床资料。入组患者的tPSA均在4~20ng/mL之间,且穿刺前均行多参数磁共振(multi-parameter magnetic resonance imaging,mpMRI)检查,并按照PI-RADSv2.1进行评分。其中2021年7月—2022年9月的患者为开发队列,2022年10月—2023年3月的患者为验证队列。分别比较2队列PCa组和非PCa组间年龄、tPSA、游离/总前列腺特异性抗原(f/tPSA)、前列腺体积(prostate volume,PV)、PI-RADSv2.1评分、PSAMR的差异。采用单因素和多因素logistic回归分析探究PSAMR及其他指标与PCa发生的关系,其中多因素分析采用向后逐步回归法。根据多因素分析结果建立预测模型,分别在2队列及整体患者中以受试者工作特征(receiver operating characteristic,ROC)曲线、校准曲线及决策曲线分析(decision curve analysis,DCA)评估模型预测性能。结果:本研究共纳入342例患者,其中病理结果显示为前列腺腺癌的患者93例,非PCa的患者249例。开发队列患者共210例,PCa患者58例,非PCa患者152例。验证队列患者132例,PCa患者35例,非PCa患者97例。基于开发队列单因素和多因素分析显示,PSAMR(OR=5.467,P=0.020)是PCa发生的危险因素。纳入构建预测模型的因素包括年龄、前列腺体积、PI-RADSv2.1评分和PSAMR。预测模型在开发队列、验证队列和总体患者的ROC曲线下面积分别为0.921、0.934和0.924,诊断效能良好。校准曲线显示预测准确性良好。DCA曲线显示该预测模型具有临床应用价值。结论:在tPSA 4~20ng/mL时,PSAMR是PCa的危险因素。纳入PI-RADSv2.1评分和PSAMR构建的预测模型可为前列腺穿刺活检决策提供参考。

关键词：前列腺特异性抗原质量比总前列腺特异抗原前列腺癌预测模型

基于超像素和超度量轮廓图的无人机图像分割算法

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计算机辅助设计与图形学学报 2019年第8期31卷 1294-1300页

作者：宋以宁刘文萍宗世祥骆有庆北京林业大学信息学院北京100083 北京林业大学林学院北京100083

为精确地分割高分辨率无人机航拍图像中的不同地物,提出一种基于超像素和超度量轮廓图的无人机图像分割算法.首先对图像进行线性谱聚类,生成超像素;然后根据HSV颜色空间的直方图特征计算超像素区域间的不相似度;再结合层次分割思想得到... 详细信息

为精确地分割高分辨率无人机航拍图像中的不同地物,提出一种基于超像素和超度量轮廓图的无人机图像分割算法.首先对图像进行线性谱聚类,生成超像素;然后根据HSV颜色空间的直方图特征计算超像素区域间的不相似度;再结合层次分割思想得到可表示边缘强度的超度量轮廓图并将其归一化;最后利用合适的阈值删除边缘强度低于该阈值的轮廓,并将所对应的区域进行合并得到分割后的图像.与ISODATA,FCM和gPb-OWT-UCM算法比较的实验结果表明,该算法图像分割准确率较高,对初始参数的依赖性小,且计算复杂度低.

关键词：无人机图像图像分割超像素线性谱聚类超度量轮廓图

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基于线性谱聚类的林地图像中枯死树监测

林业科学 2019年第4期55卷 187-195页

作者：宋以宁刘文萍骆有庆宗世祥北京林业大学信息学院北京100083 北京林业大学林学院北京100083

【目的】将基于线性谱聚类超像素的方法应用在森林病虫害防治领域,可智能监测无人机森林虫害图像中的枯死树,为森林有害生物的监测工作提供技术支撑。【方法】分别以湖北省受松材线虫与辽宁省受红脂大小蠹侵害的松林无人机图像为试验数... 详细信息

【目的】将基于线性谱聚类超像素的方法应用在森林病虫害防治领域,可智能监测无人机森林虫害图像中的枯死树,为森林有害生物的监测工作提供技术支撑。【方法】分别以湖北省受松材线虫与辽宁省受红脂大小蠹侵害的松林无人机图像为试验数据,首先使用线性谱聚类超像素分割算法将图像划分为多个超像素;然后基于枯死树木的颜色特征,初步提取可能为枯死树的超像素区域;最后基于枯死树木与其他干扰地物具有不同的纹理特征,计算超像素的区域密度和缝隙量,利用支持向量机对初步提取的超像素进行分类,从而检测出图像中的枯死树。【结果】基于线性谱聚类超像素和支持向量机的枯死树监测方法可有效排除与枯死树木颜色相近的其他干扰地物,较准确地提取出枯死树木。使用该方法与基于植被颜色指数的阈值分割方法、基于简单线性迭代聚类超像素和随机森林的方法,对35幅受灾松林无人机图像进行试验,并选用交并比、虚警率和漏检率3个评价指标对3种方法进行定量对比分析。结果表明,基于线性谱聚类超像素的方法监测出的枯死树区域最精确,其监测结果与人工检测结果的交并比均值大于58%,且虚警率和漏检率均优于另外2种方法。【结论】基于线性谱聚类超像素的枯死树监测方法能实现松林中枯死树的快速、准确检测及定位。

关键词：无人机图像分析森林病虫害枯死树监测纹理特征提取超像素线性谱聚类

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岩石压缩损伤破坏全过程试验研究

岩石力学与工程学报 2010年第A2期29卷 4180-4187页

作者：宋卫东明世祥王欣杜建华北京科技大学土木与环境工程学院北京100083

岩石的力学性质对巷道围岩稳定性及变形规律有着重要的影响。对岩样进行三轴压缩破坏全过程及峰后循环加卸载试验研究,探讨围岩超过峰值强度后的变形破坏特征;研究岩石在压缩状态及循环加、卸载条件下的破坏特征及变形机制。研究表明:(1... 详细信息

岩石的力学性质对巷道围岩稳定性及变形规律有着重要的影响。对岩样进行三轴压缩破坏全过程及峰后循环加卸载试验研究,探讨围岩超过峰值强度后的变形破坏特征;研究岩石在压缩状态及循环加、卸载条件下的破坏特征及变形机制。研究表明:(1)岩石在单轴或低围压条件下压缩表现为脆性软化特征。随着围压增大,其破坏形态逐步向压剪和塑性屈服破坏形态转变。(2)岩石在峰后区产生显著的体积扩容,且泊松比ν在峰值后区保持为一常数。(3)软岩在峰值后区的循环加卸载出现明显的摩擦滑移特征。岩石破裂后,在整个峰后变形阶段ε3与ε1均呈良好的线性关系。(4)软岩在达到峰值强度时发生破裂和滑移,峰值点即为突变点。

关键词：岩石力学三轴压缩循环加卸载峰值强度变形机制