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化工管理 2024年第3期 117-119页

作者：李婉茹何天宇王鹏勃田鑫抚顺化工机械设备制造有限公司辽宁抚顺113122

通过对螺旋扭曲管管束的制造难点与质量控制等环节的分析,阐述了扭曲管换热器的结构设计特点,分析总结螺旋扭曲管管束制造经验。以某炼化预加氢换热器换热优化改造为例,通过在实际装置中应用,验证扭曲管换热器的高效传热效率。

关键词：扭曲管结构设计连续重整

深井封隔器解封时套管挤压失效风险评估方法及应用

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钻采工艺 2024年第3期47卷 170-176页

作者：伍兴东王鹏博裴东东何勇李宁博许红林张智中国石化西北油田分公司采油四厂中国石油辽河油田公司安全环保技术监督中心重庆科技大学石油与天然气工程学院油气藏地质及开发工程国家重点实验室西南石油大学

封隔器解封时,环空液柱快速下沉将产生明显抽吸压力,导致封隔器解封后生产套管挤毁事故时有发生,给深部高温高压油井安全生产带来巨大挑战。基于规范中套管有效外压力的计算方法,考虑环空液柱下沉流速及其诱导的环空抽吸压力,建立了封... 详细信息

封隔器解封时,环空液柱快速下沉将产生明显抽吸压力,导致封隔器解封后生产套管挤毁事故时有发生,给深部高温高压油井安全生产带来巨大挑战。基于规范中套管有效外压力的计算方法,考虑环空液柱下沉流速及其诱导的环空抽吸压力,建立了封隔器解封时套管有效外压力计算方法,针对现场实例井研究了封隔器解封对套管等效支撑内压力和套管挤压失效风险的影响规律。结果表明,封隔器解封时油管液面深度越大、封隔器胶筒外径与套管内径环空间隙越大,环空抽吸压力值越大,套管内等效支撑内压力当量密度越低,套管挤压失效风险越大。为降低套管挤压失效风险,建议提高封隔器胶筒解封后变形恢复能力,同时封隔器解封前油管内应尽量补满液体。研究成果为确保深部高温高压油井安全生产提供重要理论依据和技术支撑。

关键词：套管封隔器解封挤压失效抽吸压力

Parameter vertex method and its parallel solution for evaluating the dynamic response bounds of structures with interval parameters

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Science China(Physics,Mechanics & Astronomy) 2018年第6期61卷 62-74页

作者： ZhiPing Qiu pengbo wang Institute of Solid Mechanics Beihang University Beijing 100191 China

In this article, we propose a parameter vertex method to determine the upper and lower bounds of the dynamic response of structures with interval parameters, which can be regarded as an extension of the matrix vertex method proposed by Qiu and wang. The matrix vertex method requires considerable computation time and encounters the dependency problem in practice,thereby limiting its application in engineering. The proposed parameter vertex method can avoid the dependency problem, and the number of possible vertex combinations in the proposed method is significantly less than that in the matrix vertex *** parameter vertex method requires that each matrix element in the dynamic differential equation is monotonic with respect to the uncertain parameter, and that the dynamic response reaches its extreme value when the uncertain parameter is at its *** further reduce the runtime, both vertical and transversal parallel algorithms are introduced and integrated into the parameter vertex method to improve its computational efficiency. Two numerical examples are presented to demonstrate the proposed method combined with both parallel algorithms. The performances of the two parallel algorithms are thoroughly studied. The parameter vertex method combined with parallel algorithm can be used for large-scale computing.

关键词：平行算法动态反应参数结构顶点矩阵元素评估大规模计算计算时间

车厢结构用冷轧马氏体钢电阻点焊工艺性能研究

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电焊机 2024年第5期54卷 117-123页

作者：王鹏博张永强惠亚军王泽阳伊日贵王晓雄张郢首钢集团有限公司技术研究院北京100043 首钢京唐钢铁联合有限责任公司河北唐山063200

为评估和对比1.2 mm厚的SCR1000和SCR1200冷轧马氏体钢的电阻点焊工艺性能,采用OBARA DB-220型点焊机进行电阻点焊试验,对比了两个钢种的焊接电流窗口、焊点破坏模式、力学性能、金相组织、疲劳性能。研究结果表明:随着钢材强度的提升,... 详细信息

为评估和对比1.2 mm厚的SCR1000和SCR1200冷轧马氏体钢的电阻点焊工艺性能,采用OBARA DB-220型点焊机进行电阻点焊试验,对比了两个钢种的焊接电流窗口、焊点破坏模式、力学性能、金相组织、疲劳性能。研究结果表明:随着钢材强度的提升,整体焊接电流窗口逐渐向左侧偏移,SCR1200达到最小焊核直径、焊接飞溅的焊接电流均小于SCR1000;SCR1200上限电流焊点剪切力比SCR1000提升了8.9%,而SCR1000的焊点韧性较好,其断口韧窝更细小和密集;相对熔核区和母材区,SCR1000、SCR1200的点焊接头的热影响区出现了明显的软化区,但SCR1200的软化区硬度略高。在相同载荷下,SCR1200的疲劳寿命高于SCR1000,点焊接头的疲劳强度随着钢板强度的增加而提高。

关键词：马氏体钢电阻点焊电流窗口力学性能疲劳性能

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基于改进YOLOv5的卷烟品规智能识别模型研究

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无线互联科技 2024年第8期21卷 15-17页

作者：刘晓明陈皓王朋波陶建文刘艳平陕西省烟草公司商洛分公司陕西商洛726000 商洛市烟草公司商州分公司陕西商洛726000

为实现低成本、便捷、高校的卷烟品规智能识别,降低客户经理盘点库存的时间成本,提升卷烟库存盘点效率,文章在YOLOv5模型的基础上,引入CA注意力机制,构建一种卷烟品规识别模型。针对卷烟品规识别任务,文章建立了一个多隐含层、多神经元... 详细信息

为实现低成本、便捷、高校的卷烟品规智能识别,降低客户经理盘点库存的时间成本,提升卷烟库存盘点效率,文章在YOLOv5模型的基础上,引入CA注意力机制,构建一种卷烟品规识别模型。针对卷烟品规识别任务,文章建立了一个多隐含层、多神经元节点的深度学习模型来提取卷烟外观的关键特征,同时实现了对卷烟品规和数量的识别。

关键词： YOLOv5 卷烟品规智能识别

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沙库巴曲缬沙坦治疗维持性血液透析合并慢性心力衰竭患者的临床效果

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临床医学研究与实践 2024年第2期9卷 54-57页

作者：姚转娥王鹏波付秦娟宋琼刘爱张鹏陕西省第二人民医院陕西西安710005 西京医院陕西西安710000

目的探讨沙库巴曲缬沙坦治疗维持性血液透析合并慢性心力衰竭患者的有效性和安全性。方法选取在陕西省第二人民医院血液净化中心行维持性血液透析且合并慢性心力衰竭的21例患者为研究对象,均给予沙库巴曲缬沙坦治疗12周。比较治疗前、... 详细信息

目的探讨沙库巴曲缬沙坦治疗维持性血液透析合并慢性心力衰竭患者的有效性和安全性。方法选取在陕西省第二人民医院血液净化中心行维持性血液透析且合并慢性心力衰竭的21例患者为研究对象,均给予沙库巴曲缬沙坦治疗12周。比较治疗前、后的生命体征、生化指标、心功能指标、生活质量及不良反应发生情况。结果治疗后,维持性血液透析合并慢性心力衰竭患者的收缩压、舒张压、纽约心脏病学会(NYHA)分级Ⅲ级占比、N末端B型脑钠肽前体(NT-proBNP)水平低于治疗前,左室射血分数(LVEF)高于治疗前,左室舒张末期内径(LVDD)、左室收缩末期内径(LVDS)小于治疗前(P<0.05)。治疗后,维持性血液透析合并慢性心力衰竭患者的躯体健康、精神健康评分高于治疗前(P<0.001)。结论沙库巴曲缬沙坦有利于改善维持性血液透析合并慢性心力衰竭患者的心功能及生活质量。

关键词：血液透析慢性心力衰竭沙库巴曲缬沙坦心功能生活质量

大跨度重型钢桁架屋盖固步式等高免卸载滑移施工技术

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广东土木与建筑 2024年第3期31卷 92-96页

作者：杨威王蓬勃余继军曾维锋黄朝奎张泽峰湖北精工工业建筑系统有限公司武汉430312 中建五局第三建设有限公司长沙410004

以某电子加工厂钢结构项目为例,介绍了大跨度重型钢结构桁架屋面固步式等高免卸载滑移的综合施工技术,归纳总结了该类型累积滑移施工技术和施工控制要点。滑移施工技术较常规技术而言,对安装工期和综合措施费均大有益处,为同类型的施工... 详细信息

以某电子加工厂钢结构项目为例,介绍了大跨度重型钢结构桁架屋面固步式等高免卸载滑移的综合施工技术,归纳总结了该类型累积滑移施工技术和施工控制要点。滑移施工技术较常规技术而言,对安装工期和综合措施费均大有益处,为同类型的施工安装提供借鉴。

关键词：固步式免卸载滑移重型钢桁架

Direct Synthesis of Ultrathin Crystalline Two-Dimensional Triazine Polymers from Aldoximes

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CCS Chemistry 2024年第4期6卷 932-940页

作者： Jianghong Zhen Jichuang Shen Tian Sun Congxu wang pengbo Lyu Yuxi Xu School of Engineering Westlake UniversityHangzhou 310024Zhejiang School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105Hunan

The efficient synthesis of ultrathin crystalline twodimensional(2D)polymers with well-defined repeating units is essential to realize their broad applications but remains a great ***,we report a new strategy to directly synthesize a series of few-layer 2D triazine-based polymers(2DTPs)via trimerization reaction of aromatic aldoximes in one step with a high yield of 85%using AlCl3 as catalyst under solvent-free *** obtained 2D-TPs show high crystallinity,a lateral size of several micrometers,an ultrathin thickness less than 2 nm,and good dispersibility and *** semi-in situ and detailed control experiments,we reveal that the 2D polymerization reaction is a two-step process of dehydration and then cyclotrimerization,and AlCl3 acts as not only catalyst but also an in situ generated template for promoting the formation of *** explored as a new polymeric anode for potassium-ion batteries,the 2D-TP displayed an extraordinary reversible specific capacity of 356 mAh g^(−1)at 0.05 A g^(−1),which is among the best performances ever reported,outstanding rate capability(153 mAh g^(−1)at 1 A g^(−1)),and excellent cycling stability with 95.1%capacity retention after 1000 cycles at 1 A g^(−1).

关键词： two-dimensional triazine polymer aldoxime monomers catalytic cyclotrimerization template-assisted synthesis potassium-ion battery

Advanced high-order nonlinear chirp scaling algorithm for high-resolution wide-swath spaceborne SAR

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Chinese Journal of Aeronautics 2021年第2期34卷 563-575页

作者： Zhirong MEN pengbo wang Jie CHEN Chunsheng LI Wei LIU Wei YANG School of Electronic and Information Engineering Beihang UniversityBejing 100083China Electronic and Electronic Engineering Department Univrsity of ShefeldSheffield S13JDUK

Spaceborne Synthetic Aperture Radar(SAR) is a well-established and powerful imaging technology that can provide high-resolution images of the Earth’s surface on a global scale. For future SAR systems, one of the key capabilities is to acquire images with both high-resolution and wide-swath. In parallel to the evolution of SAR sensors, more precise range models, and effective imaging algorithms are required. Due to the significant azimuth-variance of the echo signal in High-Resolution Wide-Swath(HRWS) SAR, two challenges have been faced in conventional imaging algorithms. The first challenge is constructing a precise range model of the whole scene and the second one is to develop an effective imaging algorithm since existing ones fail to process highresolution and wide azimuth swath SAR data effectively. In this paper, an Advanced High-order Nonlinear Chirp Scaling(A-HNLCS) algorithm for HRWS SAR is proposed. First, a novel Second-Order Equivalent Squint Range Model(SOESRM) is developed to describe the range history of the whole scene, by introducing a quadratic curve to fit the deviation of the azimuth FM rate. Second, a corresponding algorithm is derived, where the azimuth-variance of the echo signal is solved by azimuth equalizing processing and accurate focusing is achieved through a high-order nonlinear chirp scaling algorithm. As a result, the whole scene can be accurately focused through one single imaging processing. Simulations are provided to validate the proposed range model and imaging algorithm.

关键词： High-Resolution WideSwath(HRWS) Imaging method Second-Order Equivalent Squint Range Model(SOESRM) Signal processing Synthetic Aperture Radar(SAR)

Photon penetration depth in human brain for light stimulation and treatment:A realistic Monte Carlo simulation study

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Journal of Innovative Optical Health Sciences 2017年第5期10卷 59-68页

作者： Ting Li Chang Xue pengbo wang Yan Li Lanhui Wu Institute of Biomedical Engineering Chinese Academy of Medical Science and Peking Union Medical College 300192 TianjinP.R.China State Key Lab Elect Thin Film&Integrated Device and Department of Biomedical Engineering University of Electronic Science&Technology of China Chengdu 610054 P.R.China Design Center Avic Beijing Keeven Aviation Instrument Co. Ltd China Aviation Industry Corporation Beijing 100098P.R.China

Light has been clinically utilized as a stimulation in medical treatment,such as Low-level laser therapy and photodynamic thenapy,which has been more and more widely accepted in *** penetration depth of the treatment light is important for precision treatment and safety *** isue of light penetration has been highlighted in biomedical optics field for ***,quantitative research is sparse and even there are conflicts of view on the capability of near-infrared light penet ration into brain *** study attempts to quantitatively revisit this issue by innovative high-realistic 3D Monte Caro modeling of stimulated light penetnation within high precision Visible Chinese human *** properties of light,such as its wave-length,ilumination profle and size are concern in this *** made stra ightforward and quantitative comparisons among the ffects by the light properties(i.e.,wavelengths:660,810 and 980 nn;beam types:Gaussi an and flat beamn;bear dianeters:0,2,4 and 6 cm)which are in the range of light *** findings include about 3%of light dosage within brain tisue;the combination of Gaussian beam and 810nm light make the max imum light penetration(>5cm),which allows light to cross through gray matter into white *** study offered us,the first time as we know,quantitative guide for light stimulation parameter optimization in medical treatment.

关键词： Penetration depth light therapy light propagation MCVM human brain