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Ballistic impact response of resistance-spot-welded(RSW) double-layered plates for Q&P980 steel

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Defence Technology（防务技术） 2022年第6期18卷 1052-1064页

作者： Bo-han ma Dong-fang ma Huan-ran Wang da-nian Chen Feng-hua Zhou MOE Key Laboratory of Impact and Safety Engineering Ningbo UniversityNingbo315211China College of Science&Technology Ningbo UniversityNingbo315211China

Ballistic impact response of resistance-spot-welded(RSW)double-layered(2×1.6 mm)plates(190 mm×150 mm)for Q&P980 steel impacted by a round-nosed steel bullet(12 mm diameter and 30 mm length)was investigated by using gas gun and high-speed camera *** RSW specimens were spot welded using a 6 mm diameter electrode face producing a 7.2 mm diameter fusion zone of the spot *** ballistic curve and energy balance for the tests of the spot weld of the RSW specimens at different velocity were analyzed to characterize the ballistic behavior of the RSW specimens under bullet *** fracture mechanisms of the RSW specimens under bullet impact were *** the tests below the ballistic limit,the cracks initiated from the notch-tip and propagated along the faying surface or obliquely through the thickness depending on the impact *** the tests above the ballistic limit,the plug fracture in the front plate of the RSW specimen could be caused by the thinning-induced necking in the BM near the HAZ,while the plug fracture in the rear plate of the RSW specimens may be consist of the circumferential cracking from the rear surface and the bending fracture of the hinged part of *** effects of the electrode indentation and the weld interfaces on deformation and fracture of the RSW specimens under bullet impact were *** the tests above the ballistic limit,the circumferential fracture from the rear surface of the RSW specimens was always initiated along the interior periphery of the electrode indentation and the crack paths were along the FZ/CGHAZ or CGHAZ/FGHAZ *** the circumferential crack also formed outside the electrode indentation,the fracture on the BM/HAZ interface could be *** the front plate of the RSW specimens,the shear/bending induced cracking from the notch-tip were observed and the crack paths were along the FZ/CGHAZ or CGHAZ/FGHAZ interface.

关键词： RSW Q&P980 steel Ballistic impact Deformation Fracture

基于ILSO-DELM的燃气轮机压气机故障预警方法

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电工电气 2024年第5期 63-68页

作者：马梦甜茅大钧蒋欢春上海电力大学自动化工程学院上海200090 上海明华电力科技有限公司上海200090

压气机结构复杂,运行特性为非线性的特点加大了燃气轮机压气机故障预警的难度,为了提高燃气轮机压气机故障预警能力,提出了一种基于改进的狮群优化算法(ILSO)优化深度极限学习机(DELM)的故障预警方法。通过皮尔逊相关分析得到与预警参... 详细信息

压气机结构复杂,运行特性为非线性的特点加大了燃气轮机压气机故障预警的难度,为了提高燃气轮机压气机故障预警能力,提出了一种基于改进的狮群优化算法(ILSO)优化深度极限学习机(DELM)的故障预警方法。通过皮尔逊相关分析得到与预警参数相关性高的测点,构建ILSO-DELM预测模型,得到正常状态下预警参数的绝对值,通过参数估计确定阈值,根据残差绝对值是否超过预警线来间接判断压气机的运行情况。以上海某燃机电厂的运行数据进行分析,通过验证表明:该方法能够对压气机故障提前预警,并且相比于DELM模型预测精度更高。

关键词：压气机深度极限学习机狮群优化算法故障预警

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国外无人潜航器技术发展热点分析

舰船科学技术 2024年第4期46卷 185-189页

作者：张大中韩冬梅马晓晨丁宏中国船舶集团有限公司第七一四研究所北京100101

基于科学引文索引数据库及相关科技文献数据,分析国外军用无人潜航器技术的研究热点,着重研究无人潜航器技术军事应用重点解决的问题和对未来作战的影响。相关结果初步勾勒国外军用无人潜航器技术发展全貌,可为理清军用无人潜航器技术... 详细信息

基于科学引文索引数据库及相关科技文献数据,分析国外军用无人潜航器技术的研究热点,着重研究无人潜航器技术军事应用重点解决的问题和对未来作战的影响。相关结果初步勾勒国外军用无人潜航器技术发展全貌,可为理清军用无人潜航器技术方向提供参考。

关键词：无人潜航器自主性指挥控制无人集群通信导航

An oxygenating colloidal bioink for the engineering of biomimetic tissue constructs

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Bio-Design and manufacturing 2024年第3期7卷 240-261页

作者： Seol-Ha Jeong Jarno Hiemstra Patrick V.Blokzijl Rebeca damian-Ferrara danilo ma.tins dos Santos Jéssica H.L.da Fonseca Min-Ho Kang Jihyun Kim Dilara Yilmaz-Aykut Mei L.L.Cham-Pérez Jeroen Leijten Su Ryon Shin Division of Engineering in Medicine Department of MedicineBrigham and Women’s HospitalHarvard Medical SchoolBostonMA 02139USA Leijten Lab Department of Developmental BioEngineeringFaculty of Science and TechnologyTechnical Medical CentreUniversity of TwenteDrienerlolaan 57522 NB EnschedeThe Netherlands Nanotechnology National Laboratory for Agriculture(LNNA) Embrapa InstrumentaçãoSao CarlosSao Paulo 13560-970Brazil Department of Biomedical-Chemical Engineering The Catholic University of Korea43 Jibong-roBucheon-siGyeonggi-do 14662Republic of Korea Department of Biotechnology The Catholic University of Korea43 Jibong-roBucheon-siGyeonggi-do 14662Republic of Korea

Ensuring a sufficient oxygen supply is pivotal for the success of bioprinting applications since it fosters tissue integration and natural *** in oxygen concentration among diverse tissues necessitates the precise recreation of tissue-specific oxygen levels in imprinted constructs to support the survival of targeted *** oxygen-releasing biomaterials,such as oxygen-generating microparticles(OMPs),have shown promise for enhancing the oxygen supply of microenvironments in injured tissues,whether this approach is scalable for large tissues and whether tissue-specific bioinks with varying OMP concentrations remain printable remain *** study addresses this critical gap by introducing an innovative class of engineered oxygenated bioinks that combine colloidal-based microgels with *** report that incorporating nanosized calcium peroxide(nCaO_(2))and manganese oxide nanosheets(nMnO_(2))into hydrophobic polymeric microparticles enables precise modulation of oxygen release while controlling hydrogen peroxide ***,the fabrication of oxygenating and cytocompatible colloidal gels is achieved using an aqueous two-phase *** study thoroughly evaluates the fundamental characteristics of the resulting bioink,including its rheological behaviors,printability,shape fidelity,mechanical properties,and oxygen release ***,this study demonstrates the macroscopic scalability and cytocompatibility of printed constructs produced via cell-laden oxygenating colloidal *** showcasing the effectiveness of extrusion-based bioprinting,this study underscores how it can be used to fabricate biomimetic tissues,indicating its potential for new *** findings presented here advance the bioprinting field by achieving scalability with both high cell viability and the possibility of mimicking specifically oxygenated *** work thereby offers a promising avenue for the development of functional tissues with e

关键词： 3D bioprinting Bioink Colloidal gels Extrusion printing Oxygen-generating microparticle

Wafer-scale 30°twisted bilayer graphene epitaxially grown on Cu_(0.75)Ni_(0.25)(111)

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Chinese Physics B 2024年第6期33卷 467-471页

作者：马鹏程张翱甄洪润江志诚杨逸尘丁建阳刘正太刘吉山沈大伟于庆凯刘丰张学富刘中灏 School of Physical Science and Technology Ningbo UniversityNingbo 315211China Institute of High-Pressure Physics Ningbo UniversityNingbo 315211China National Key Laboratory of materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China Center of materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China

Twisted bilayer graphene(TBG) has been extensively studied because of its novel physical properties and potential application in electronic *** we report the synthesis and characterization of 300 TBG naturally grown on Cu_(0.75)Ni_(0.25)(111) film and investigate the electronic structure by angle-resolved photoemission *** with other substrates,our TBG with a wafer scale is acquired with a shorter growth *** Fermi velocity and energy gap of Dirac cones of TBG are comparable with those of a monolayer on Cu_(0.85)Ni_(0.15)(111).The signature of moré lattices has not been observed in either the low-energy electron diffraction patterns or the Fermi surface map within experimental resolution,possibly due to different Cu and Ni contents in the substrates enhancing the different couplings between the substrate and the first/second layers and hindering the formation of a quasiperiodic structure.

关键词： twisted bilayer graphene electronic structure Cu/Ni(111)

What decarbonized the residential building operation worldwide since the 2000s

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Petroleum Science 2022年第6期19卷 3194-3208页

作者： Min-da ma Min-Xia Chen Wei Feng Jing-Wen Huo Building Technology&Urban Systems Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720United States School of management Science and Real Estate Chongqing UniversityChongqing400045PR China Department of Earth System Science Tsinghua UniversityBeijing100084PR China

Decarbonization in operational residential buildings worldwide has become critical in achieving the carbon neutral target due to the growing household energy *** accelerate the pace of global carbon neutrality,this study explores the operational carbon change in global residential buildings through the generalized Divisia index method and decoupling analysis,considering the decarbonization levels of residential buildings at different *** results show that(1)most of the samples showed a decrease in the total emissions from 2000 to *** for China and the United States(US),the carbon emissions in global residential building operations decreased by 7.95 million tons of carbon dioxide(MtCO_(2))per year over the study *** per gross domestic product(GDP)was the most positive driver causing the decarbonization of residential buildings,while GDP was the most negative driver.(2)Carbon intensity was essential to achieving a strong decoupling of economic development and carbon *** US almost consistently presented strong decoupling,while China showed weak decoupling over the last two decades.(3)The pace of decarbonization in global residential building operations is gradually slowing *** 2000 to 2019,decarbonization from residential buildings across 30 countries was 2094.3 MtCO_(2),with a decarbonization efficiency of 3.4%.Overall,this study addresses gaps in evaluating global decarbonization from operational residential buildings and provides a reference for evaluating building decarbonization by other emitters.

关键词： Global residential building Operational decarbonization Generalized divisia index method Decoupling elasticity Building decarbonization strategies

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超声全聚焦成像的裂纹类缺陷定量误差分析

中国测试 2024年第2期50卷 136-145页

作者：康达孔庆茹马啸啸林珊珊张宏马兆光吴慧慧陈尧北京动力机械研究所北京100074 北京航空航天大学机械工程及自动化学院北京100083 南昌航空大学无损检测技术教育部重点实验室江西南昌330063

虽然超声全聚焦成像(total focusing method,TFM)具有直观显示裂纹特征的明显优势,但通过TFM图像进行裂纹定量时不可避免地出现测量误差。该文采用模拟与实验对比的方式,分析TFM技术的裂纹定量误差。从超声波波长对缺陷深度的影响规律入... 详细信息

虽然超声全聚焦成像(total focusing method,TFM)具有直观显示裂纹特征的明显优势,但通过TFM图像进行裂纹定量时不可避免地出现测量误差。该文采用模拟与实验对比的方式,分析TFM技术的裂纹定量误差。从超声波波长对缺陷深度的影响规律入手,分析和研究裂纹长度和取向的全聚焦图像测量误差原因。最后,通过模拟实验对比的方式验证裂纹定量误差。研究结果表明,裂纹上、下尖端的测量深度比实际深度均有所下沉,但两者下沉的深度基本相同,相差在0.6 mm以内,裂纹长度的测量误差范围为0~1 mm,带取向裂纹的取向测量误差基本保持在3°以内。因此,上、下尖端在深度上的测量误差对裂纹长度和取向的影响极小。经实验验证,裂纹深度、长度及取向误差的结论与模拟的结论一致。

关键词：超声全聚焦定量误差裂纹长度裂纹取向

同方期刊数据库博看期刊评论

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分布式电力交易系统安全威胁与检测

计算机应用 2024年第S1期44卷 112-117页

作者：李达马军伟郭庆雷柏德胜徐若然清华大学电机工程与应用电子技术系北京100084 国网数字科技控股有限公司北京100053 国网山西省电力公司太原030021 国网区块链应用技术实验室北京100053 国网区块链科技(北京)有限公司北京100053

随着电力系统网络化改革的逐步深入,融合“互联网+用户深度参与”的电力市场交易多元化新模式受到广泛关注。作为典型的应用案例,基于区块链的分布式电力交易系统由于可为多方电力交易参与方提供可靠的电力消纳能力,显示出巨大的应用潜... 详细信息

随着电力系统网络化改革的逐步深入,融合“互联网+用户深度参与”的电力市场交易多元化新模式受到广泛关注。作为典型的应用案例,基于区块链的分布式电力交易系统由于可为多方电力交易参与方提供可靠的电力消纳能力,显示出巨大的应用潜力。然而,当前对分布式电力交易系统自身的安全性讨论较少,导致节点间可能存在的恶意行为及其安全威胁难以被清晰地描述,相关安全检测方案难以实施,从而为系统运行的稳定性遗留了安全隐患。为此,分析分布式电力交易系统面临的安全威胁,并在此基础上设计了基于深度学习的安全威胁检测方案。首先,设计面向区块链节点的全量流量数据采汇方法,并清洗冗余数据;其次,设计了基于长短期记忆网络和自动编码器技术融合的特征数据训练方案,以实现对特征化节点安全状态数据的高效学习和异常检测。在国家电网示范性区块链平台上展开实验评估,实验结果表明,所提方案具备良好的检测能力和较低的性能开销,适用于提升分布式电力交易系统的安全性。

关键词：区块链分布式电力交易系统安全威胁安全检测深度学习

儿童肱骨髁上骨折的多层螺旋CT后处理诊断研究

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中国城乡企业卫生 2024年第6期39卷 11-13页

作者：孙大昂马红丽滕州市中心人民医院小儿外科山东滕州277599 山东省滕州市中心人民医院影像中心

目的分析儿童肱骨髁上骨折的多层螺旋CT后处理的诊断效果,为儿童肱骨髁上骨折的诊断提供参考。方法选取2021年1月—2022年12月滕州市中心人民医院收治的60例儿童肱骨髁上骨折患儿为研究对象,患儿均进行多层螺旋CT平扫和CT后处理,分析两... 详细信息

目的分析儿童肱骨髁上骨折的多层螺旋CT后处理的诊断效果,为儿童肱骨髁上骨折的诊断提供参考。方法选取2021年1月—2022年12月滕州市中心人民医院收治的60例儿童肱骨髁上骨折患儿为研究对象,患儿均进行多层螺旋CT平扫和CT后处理,分析两种方法图像特点,并对比两种诊断效能。结果多层螺旋CT后处理技术的灵敏度、特异度、准确度为98.33%、98.33%及100.00%,均高于多层螺旋CT平扫的86.67%、83.33%及88.33%,差异均有统计学意义(χ^(2)=4.324、6.405、5.461,P<0.05)。多层螺旋CT平扫结果显示,肱骨髁上骨质连续性中断,断端对位欠佳患儿53例、占88.33%;断端可见游离小骨块患儿35例、占58.33%。多层螺旋CT后处理技术结果显示,骨折远端旋转约30°的患儿38例、占63.33%,骨折远端旋转10°~15°的患儿22例、占36.67%。结论运用多层螺旋CT后处理技术诊断儿童肱骨髁上骨折优势明显,可更加准确、多角度地显示肱骨髁上骨折情况,明显提高患儿骨折诊断的准确性,具有较高的临床应用价值。

关键词：儿童肱骨髁上骨折多层螺旋CT后处理诊断效果