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Evidence for the Reliability and Validity of the Arabic Version of the Student Risk Screening Scale for Internalizing and Externalizing Behaviors (SRSS-IE)
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作者 Sumayah A. Alrubayie Keetam D. F. Alkahtani 《Journal of Behavioral and Brain Science》 2024年第1期32-45,共14页
School-based universal screening for behavioral/emotional risk is a necessary first step to providing services in an educational setting for students with emotional and behavioral disorders (EBDs). Psychometric proper... School-based universal screening for behavioral/emotional risk is a necessary first step to providing services in an educational setting for students with emotional and behavioral disorders (EBDs). Psychometric properties are critical to making decisions about choosing a screening instrument. The purpose of the present study was to examine the psychometric properties of the student risk screening scale for internalizing and externalizing behaviors (SRSS-IE). Participants included 3145 students and their teachers. Item-level analyses of the current sample supported the retention of all items. The internal consistency of the SRSS items ranged from 0.83 to 0.85. Convergent validity between the SRSS-IE and a well-established screening tool, the strength and difficulties questionnaire (SDQ), was found for the total score (r = 0.70). Additionally, the results of this study demonstrate strong social validity, suggesting the SRSS-IE to be a useful and functional screening tool. We conclude that the SRSS-IE is a valid and reliable instrument for assessing the level of emotional and behavioral difficulties among elementary students. 展开更多
关键词 the Student Risk Screening Scale for internalizing and Externalizing Behaviors (SRSS-IE) Strength and Difficulties Questionnaire (SDQ) Emotional and Behavioral Difficulties Screening tools Systematic Screening
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Evaluating the Role of Internal Factors in the Damage and the Methods of Treatment of the Limestone of Emir Hasan Mosque in Akhmim, Sohag, Egypt
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作者 Elashmawy A. Abd-Elkareem 《Open Journal of Geology》 2020年第12期1280-1295,共16页
The present paper examines the deterioration of the limestone of Emir Hasan Mosque as a result of internal damage factors. Tests were done and carried to determine the rate of damage to the limestone that was used in ... The present paper examines the deterioration of the limestone of Emir Hasan Mosque as a result of internal damage factors. Tests were done and carried to determine the rate of damage to the limestone that was used in the past in Egypt. Chemical analyses were done to identify soluble salts. The study utilized optical microscopy, scanning electron microscope equipped with EDS unit, and X-ray diffraction analysis to identify the main causes of increased limestone damage rates because of being affected by internal destructive factors. The study discussed different ways to conserve separate parts through the use of one consolidated material through the study of changes to limestone during the period of treatment to determine the appropriate treatment methods. 展开更多
关键词 Emir Hasan Mosque internal Factors damage LIMEStoNE Treatment
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Mitochondrial transplantation ameliorates hippocampal damage following status epilepticus 被引量:2
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作者 Xiaoxia Jia Qinghua Wang +5 位作者 Jianlun Ji Wenchun Lu Zhidong Liu Hao Tian Lin Guo Yun Wang 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第1期41-50,共10页
Background:Hippocampal damage caused by status epilepticus(SE)can bring about cognitive decline and emotional disorders,which are common clinical comorbidities in patients with epilepsy.It is therefore imperative to d... Background:Hippocampal damage caused by status epilepticus(SE)can bring about cognitive decline and emotional disorders,which are common clinical comorbidities in patients with epilepsy.It is therefore imperative to develop a novel therapeutic strat-egy for protecting hippocampal damage after SE.Mitochondrial dysfunction is one of contributing factors in epilepsy.Given the therapeutic benefits of mitochondrial replenishment by exogenous mitochondria,we hypothesized that transplantation of mitochondria would be capable of ameliorating hippocampal damage following SE.Methods:Pilocarpine was used to induced SE in mice.SE-generated cognitive de-cline and emotional disorders were determined using novel object recognition,the tail suspension test,and the open field test.SE-induced hippocampal pathology was assessed by quantifying loss of neurons and activation of microglia and astrocytes.The metabolites underlying mitochondrial transplantation were determined using metabonomics.Results:The results showed that peripheral administration of isolated mitochon-dria could improve cognitive deficits and depressive and anxiety-like behaviors.Exogenous mitochondria blunted the production of reactive oxygen species,pro-liferation of microglia and astrocytes,and loss of neurons in the hippocampus.The metabonomic profiles showed that mitochondrial transplantation altered multiple metabolic pathways such as sphingolipid signaling pathway and carbon metabolism.Among potential affected metabolites,mitochondrial transplantation decreased levels of sphingolipid(d18:1/18:0)and methylmalonic acid,and elevated levels of D-fructose-1,6-bisphosphate.Conclusion:To the best of our knowledge,these findings provide the first direct ex-perimental evidence that artificial mitochondrial transplantation is capable of amelio-rating hippocampal damage following SE.These new findings support mitochondrial transplantation as a promising therapeutic strategy for epilepsy-associated psychiat-ric and cognitive disorders. 展开更多
关键词 cognitive deficit emotional disorders hippocampal damage mitochondrial transplantation status epilepticus
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Damage and geological assessment of the 18 September 2011 M_w 6.9 earthquake in Sikkim,India using very high resolution satellite data 被引量:7
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作者 Tapas R.Martha K.Babu Govindharaj K.Vinod Kumar 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第6期793-805,共13页
Post-disaster very high resolution(VHR) satellite data are potential sources to provide detailed information on damage and geological changes for a large area in a short time.In this paper,we studied landslides trig... Post-disaster very high resolution(VHR) satellite data are potential sources to provide detailed information on damage and geological changes for a large area in a short time.In this paper,we studied landslides triggered by the M_w 6.9 earthquake in Sikkim,India which occurred on 18 September 2011 using VHR data from Cartosat-1,GeoEye-1,QuickBird-2 and WorldView-2 satellites.Since the earthquake-affected area is located in mostly inaccessible Himalayan terrain,VHR data from these satellites provided a unique opportunity for quick and synoptic assessment of the damage.Using visual change analysis technique through comparison of pre- and post-earthquake images,we assessed the damage caused by the event.A total of 123 images acquired from eight satellites,covering an area of4105 km2 were analysed and 1196 new landslides triggered by the earthquake were mapped.Road blockages and severely affected villages were also identified.Geological assessment of the terrain highlighted linear disposition of landslides along existing fault scarps,suggesting a reactivation of fault.The landslide inventory map prepared from VHR images also showed a good correlation with the earthquake shake map.Results showed that several parts of north Sikkim,particularly Mangan and Chungthang,which are close to the epicentre,were severely affected by the earthquake,and that the event-based landslide inventory map can be used in future earthquake-triggered landslide susceptibility assessment studies. 展开更多
关键词 International Charter damage Landslide Fault VHR Disaster
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MicroRNA-based targeting of the Rho/ROCK pathway in therapeutic strategies after spinal cord injury 被引量:1
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作者 Tetsu Kimura Yuta Horikoshi 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第2期311-312,共2页
Spinal cord injury(SCI)is one of the leading causes of disability and is a devastating condition that requires long-term care,reduces social productivity,and gives an immense emotional burden on patients and their fa ... Spinal cord injury(SCI)is one of the leading causes of disability and is a devastating condition that requires long-term care,reduces social productivity,and gives an immense emotional burden on patients and their fa milies.SCI frequently occurs due to traffic accidents,falls,slips,violence,sports,and medical accidents in today's society.The initial mechanical damage triggers a secondary injury cascade that induces more intractable damage(Silva et al.,2014).Secondary injury mechanisms have been postulated,including neuronal apoptosis,inflammation,oxidative stress,and excitotoxicity. 展开更多
关键词 damage INJURY EMOTIONAL
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“Emotional Dwarfism”Is a Failure to Thrive Emotionally-Whence the Childhood Roots of Hate,Psychosis,Violence,and Nucleargeddon-All Curable 被引量:1
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作者 Bob Johnson 《Journal of Philosophy Study》 2022年第2期78-92,共15页
VIOLENCE IS NOT ONLY WRONG,IT’S DISEASED-it’s always painful and too often fatal-as with Martin Luther King,no less.When emotions run high,doctors have difficulty making progress-calm,dispassionate review of the obv... VIOLENCE IS NOT ONLY WRONG,IT’S DISEASED-it’s always painful and too often fatal-as with Martin Luther King,no less.When emotions run high,doctors have difficulty making progress-calm,dispassionate review of the obvious evidence is vital,if you aim for less pain and fewer deaths.This paper is based on the self-evident precept that violated children unmistakeably predate violent adults.The remedy,highlighted here,is unusual in all psychiatry,in that it is backed by solid,irrefutable,objective,scientific evidence-from brainscans,no less-at least it is,for those willing to look.The paper has 6 parts:1.Introduction;2.Un-memorising Terror;3.Nutritious Emotions;4.Tyrannical Revenge;5.The Way to Cure Nucleargeddon Is Paved With Good Intentions;6.Conclusion.Parenting is a troubled skill,largely because mis-parenting perpetuates itself.As the poet Philip Larkin says of parents-“they fill you with the faults they had,and add some extra just for you”.Larkin moderates his criticism with“they may not mean to,but they do”.Sadly his“solution”-“don’t have any kids yourself”can extinguish the human race as reliably as ever revengeful Emotional Dwarfism will. 展开更多
关键词 emotional infantilisms Hitler’s blindspot Hitler’s internal memorised monster curing violence curing hate curing psychoses ways to escape our thermonuclear Armageddon
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Remedies for loss and damage caused by climate change from the dimension of climate justice
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作者 Mingde Cao Qi Wang Yu Cheng 《Chinese Journal of Population,Resources and Environment》 2016年第4期253-261,共9页
Adverse consequences to the ecological system and human health caused by impacts potentially attributable to climate change have already drawn great and widespread concern of many scientists and international organiza... Adverse consequences to the ecological system and human health caused by impacts potentially attributable to climate change have already drawn great and widespread concern of many scientists and international organizations.However,we still have a hard time determining exactly the impact of climate change on the environment or the damage that climate change inflicts on countries comprising small islands or low-lying lands in light of today's science and technology.The progress for dealing with the issue of loss and damage has been struggling for a long time from the beginning to the present.In this paper,the author begins by summarizing talks on the concept and the positions of commentators.The author is proposing that the development of future climate negotiations and rule-making process be based on global climate justice as a standard for measuring value.Also,the author proposes that a holistic view of climate justice be established.Generally,three aspects of climate justice can be derived.First,the dimension of human rights protection shows that protection of fundamental human rights is a logical precondition if small-island and low-lying countries are able to achieve climate justice.Second,the definite and traditional concepts of distributive justice and corrective justice hold the view that the principle of common but differentiated responsibilities should be upheld as a basic standard of allocating rights and duties associated with climate change.Third,climate justice requires that any state follow the "no-harm principle," which is regarded as an international customary rule.According to the principle,the obligation of states to prevent the use of their territory for causing trans-boundary harm to the environment shall be a violation of state responsibility,which incurs international punishment.Then we put forward three remedial approaches in light of climate justice,including the approach of State Responsibility(SR) based on the principles and rules of international human rights law and international environmental law.Based on clear rules,the judge can determine whether the damaging behavior or the damage perpetrated by a state party constitutes a state responsibility.The International Environmental Regulation(IEB),which means solving the problems within the framework established by the Conventions on Climate Change,takes advantage of the market mechanisms and incentives such as fund and insurance support system to relieve or compensate the loss and damage.International Environmental Dispute Settlement Mechanism(IEDSM),which includes the means such as consultations,negotiations,nonmandatory ways and international arbitration,international judicial ways to solve these disputes,functions as a procedural safeguard.As an active promoter of global climate governance,China should no doubt stand by the principle of Common But Differentiated Responsibility(CBDR) and take it as a basis for negotiations,actively strengthen the work of South-South cooperation,fulfill her international climate commitments without reservation,vigorously develop a low-carbon economy,and actively promote international negotiations on the subject of loss and damage. 展开更多
关键词 Loss and damage climate justice principle of CBDR state responsibility international environmental regulation
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Identification of Internal Damage in Circular Cylinders through Laser Scanning of Vibrating Surfaces
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作者 Yisu Xi Binkai Shi +3 位作者 Wei Xu Jing Ge Huaxin Zhu Dragoslav Sumarac 《Structural Durability & Health Monitoring》 EI 2022年第2期163-177,共15页
With the aid of non-contact measurements of vibrating surfaces through laser scanning,operating deflection shapes(ODSs)with high spatial resolutions can be used to graphically characterize damage in plane structures.A... With the aid of non-contact measurements of vibrating surfaces through laser scanning,operating deflection shapes(ODSs)with high spatial resolutions can be used to graphically characterize damage in plane structures.Although numerous damage identification approaches relying on laser-measured ODSs have been developed for plate-type structures,they cannot be directly applied to circular cylinders due to the gap between equations of motions of plates and circular cylinders.To fill this gap,a novel approach is proposed in this study for damage identification of circular cylinders.Damage-induced discontinuities of the derivatives of ODSs can be used to gra-phically manifest the occurrence of the damage,and characterize the location and size of the damage.The approach is experimentally validated on a specimen of the circular cylinder component,whose out-of-plane ODSs in an inspection region are acquired through laser scanning using a scanning laser vibrometer.The results suggest that the occurrence,location,and size of the internal damage of the circular cylinder can be identified. 展开更多
关键词 internal damage identification circular cylinder non-contact vibration measurement laser scanning operating deflection shape
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钢筋锈蚀作用下隧道衬砌结构力学性能劣化研究
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作者 李永珑 刘新华 +2 位作者 朱星宇 唐旭 张志强 《铁道学报》 EI CAS CSCD 北大核心 2024年第1期156-163,共8页
考虑锈蚀引起的钢筋力学性能劣化、混凝土有效截面减少、两者黏结性能退化等因素,建立围岩压力作用下钢筋锈蚀隧道衬砌模型,对不同锈蚀率下衬砌结构变形、损伤、内力重分布和裂缝宽度变化进行分析。研究结果表明,锈蚀对衬砌结构各部位... 考虑锈蚀引起的钢筋力学性能劣化、混凝土有效截面减少、两者黏结性能退化等因素,建立围岩压力作用下钢筋锈蚀隧道衬砌模型,对不同锈蚀率下衬砌结构变形、损伤、内力重分布和裂缝宽度变化进行分析。研究结果表明,锈蚀对衬砌结构各部位损伤严重程度表现为拱顶>拱肩>拱脚>拱腰>仰拱;锈蚀引起结构内力重分布,当锈蚀率由0%发展到20%时,衬砌结构临空侧受拉处弯矩逐渐减小,围岩侧受拉处的弯矩逐渐增大,衬砌轴力整体变化不大,最大变化量仅为7.53%;拱顶裂缝宽度发展最快,拱肩和拱脚次之,当锈蚀率发展到2.7%时,拱顶最大裂缝宽度已不满足耐久性要求;开裂区钢筋锈蚀对衬砌力学性能劣化起主导作用,仅开裂区钢筋发生锈蚀时,衬砌结构力学性能劣化规律与钢筋全长锈蚀情况类似,但锈蚀导致的内力变化幅度和裂缝宽度减小。 展开更多
关键词 衬砌结构 混凝土损伤 锈蚀 内力重分布 裂缝宽度
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钢筋混凝土结构移动式精准检测技术开发 被引量:1
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作者 吴智深 侯士通 +1 位作者 黄玺 黄璜 《工程力学》 EI CSCD 北大核心 2024年第1期1-16,共16页
无损检测技术是一种在不损害材料及结构服役性能的前提下,对其性质进行评估和测量的检测技术。然而,随着无损检测技术的发展和实践,结构内部的复杂损伤检测缺乏多层次精准性成为该领域的难点和核心问题。该文旨在结合国内外的研究成果,... 无损检测技术是一种在不损害材料及结构服役性能的前提下,对其性质进行评估和测量的检测技术。然而,随着无损检测技术的发展和实践,结构内部的复杂损伤检测缺乏多层次精准性成为该领域的难点和核心问题。该文旨在结合国内外的研究成果,对无损检测技术的发展、分类和挑战进行梳理和分析,并在此基础上,介绍作者研究团队建立的一套由宏观到细观,再到内部的全面精准检测系统研究成果。针对表面宏观识别与细观定量识别,作者团队开发了表观病害视觉检测技术,包括构建的空间基准点自动追踪融合和亚像素级病害分割的全景图像快速拼接及表观病害厘米级定位方法,以及提出的全景图像中0.05 mm~0.2 mm多尺寸微细裂缝同步识别及真伪判别的人工智能算法。针对结构内部损伤识别,作者团队首创了智能变频敲击声波扫描及各类损伤精准识别新原理,发明建立了自适应激励分布移动敲击声波的损伤检测评估理论方法、声波及声纹图像特征人工智能算法及智能装备关键技术。经过实验验证,裂缝检测中宽度为0.05 mm时最大深度可达40 mm,剥离检测中最大深度可达400 mm,最小识别范围为50 mm。 展开更多
关键词 无损检测 变频敲击 图像处理 内部损伤 裂缝识别 钢筋混凝土 敲击检测
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FBG传感器在起重机械局部损伤监测中的应用研究
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作者 尚歌 王雁飞 《传感技术学报》 CAS CSCD 北大核心 2024年第7期1285-1289,共5页
光纤布拉格光栅(Fiber Bragg Grating,FBG)传感器自身应变传递特性和敏感范围波动较大,在应用过程中缺少结合被测结构性能和FBG传感器本身结构特点的应用方法。为此,研究FBG传感器在起重机械局部损伤监测中的应用。根据起重机械的内部... 光纤布拉格光栅(Fiber Bragg Grating,FBG)传感器自身应变传递特性和敏感范围波动较大,在应用过程中缺少结合被测结构性能和FBG传感器本身结构特点的应用方法。为此,研究FBG传感器在起重机械局部损伤监测中的应用。根据起重机械的内部振动状况构建损伤模型,在FBG传感器光纤的同一位置放置两个不同的Bragg光栅,并根据波长变化采集局部损伤数据,将采集到的数据输入自回归滑动平均模型(Autoregressive Moving Average Model,ARMA)中,提取损伤状态,完成起重机械局部损伤监测。实验结果表明,所提方法的反馈时间低于0.25 ms,监测到的应变数据与实际应变数据差距相近,监测的损伤部位与设定损伤部位一致,证明该方法监测反馈效率和监测精度高,监测效果好,适用于各种环境下的起重机械局部监测工作。 展开更多
关键词 FBG传感器 局部损伤监测 BRAGG光栅 起重机械 ARMA模型 内部振动
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外包式柱脚传力机理及内力分布研究
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作者 徐艳秋 刘洪雨 《山西建筑》 2024年第15期41-44,共4页
为探究外包式柱脚的传力机理及内力分布状况,基于塑性损伤理论建立了外包式柱脚有限元仿真模型。通过模拟数据分析了钢柱在加载过程中各截面内力变化,研究了钢柱与外包层之间的相互作用机制及内力传递机理;对有、无栓钉外包式柱脚的内... 为探究外包式柱脚的传力机理及内力分布状况,基于塑性损伤理论建立了外包式柱脚有限元仿真模型。通过模拟数据分析了钢柱在加载过程中各截面内力变化,研究了钢柱与外包层之间的相互作用机制及内力传递机理;对有、无栓钉外包式柱脚的内力分布进行了对比,研究了栓钉在内力传递过程中的作用及影响。研究结果表明,内力通过钢柱与外包层之间界面的接触应力及栓钉的作用力进行传递,在柱脚底部截面钢柱已将大部分内力传递给外包层;栓钉在内力传递过程中发挥了积极的作用,促进了钢柱将内力传递给外包层;布置栓钉有利于减轻钢柱底板下面混凝土的局部承压,改善锚栓的受力状况。 展开更多
关键词 外包式柱脚 塑性 损伤 传力机理 有限元 内力 栓钉
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适用2000 HSC CODE的高速船特点及总体设计要求
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作者 张伟 曲宁宁 段玉龙 《船舶》 2024年第3期60-67,共8页
高速船由于其航速高、质量轻、营运特殊等特点,需要适用的规则与常规船型不同。2000年的《国际高速船安全规则》(简称2000 HSC CODE)作为较完备的适用于高速船的规则,被各海事主管机关广泛接受作为高速船的设计依据。文中简要介绍2000 H... 高速船由于其航速高、质量轻、营运特殊等特点,需要适用的规则与常规船型不同。2000年的《国际高速船安全规则》(简称2000 HSC CODE)作为较完备的适用于高速船的规则,被各海事主管机关广泛接受作为高速船的设计依据。文中简要介绍2000 HSC CODE的安全原理,以及该规则对各海事主管机关的适用程度;然后通过国内外高速船事故来分析该类船的事故类型及致因特点,并进一步介绍了适用高速船的风险控制及设计措施,包括营运限制、破舱稳性、防火要求和撤离分析等总体设计要求,以供理解高速船的安全原理并指导其设计。 展开更多
关键词 国际高速船安全规则 安全原理 高速船事故 营运限制 船底破损 阻火分隔
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基于红外热像的车站混凝土结构损伤智能检测方法
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作者 王静 毅力果奇 +1 位作者 杨俊 谢辉 《城市建筑》 2024年第12期1-4,共4页
车站作为一种典型的混凝土建筑,受工艺和材料配比的限制,大多数混凝土结构均具有一定的内部缺陷。因此,为了保证车站人员的安全,研究提出了一种基于红外热像及掩膜循环卷积神经网络的混凝土结构内部损伤智能检测方法。实验结果显示,该... 车站作为一种典型的混凝土建筑,受工艺和材料配比的限制,大多数混凝土结构均具有一定的内部缺陷。因此,为了保证车站人员的安全,研究提出了一种基于红外热像及掩膜循环卷积神经网络的混凝土结构内部损伤智能检测方法。实验结果显示,该方法对不同类型缺陷的检测精度最高为99.7%,最低为93.3%;Io U最高为98.4%,最低为91.5%。在缺陷尺寸量化中,预测尺寸与实际尺寸的比值均趋近于1,二者的相对误差最大为1.35%,最小为0.04%,平均相对误差为0.70%。在实际应用中,智能检测模型的平均精度均值、平均Io U和平均召回率分别为92.1%、90.2%和84.4%,相较于测试中有所下降,但仍保持在良好水平上。上述结果表明,基于红外热像及掩膜循环卷积神经网络的智能检测模型能有效实现混凝土内部损伤的准确检测,有效保障车站混凝土结构的性能。 展开更多
关键词 混凝土 内部损伤 红外热像 Mask R-CNN 无损检测
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载人航天商业化的国际损害责任制度:困境与应对 被引量:2
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作者 龙杰 陈文真 《武大国际法评论》 2024年第1期118-138,共21页
载人航天商业化的发展需要平衡外层空间的公共性和商业载人航天的私营性,国际损害责任制度对管控商业载人航天的成本和风险至关重要。国际外空法对国际损害责任进行了一般性、原则性规定,部分航天国家在国内法中对商业载人航天的损害责... 载人航天商业化的发展需要平衡外层空间的公共性和商业载人航天的私营性,国际损害责任制度对管控商业载人航天的成本和风险至关重要。国际外空法对国际损害责任进行了一般性、原则性规定,部分航天国家在国内法中对商业载人航天的损害责任予以明确。基于外空领域的现有责任规则,构建国际损害责任制度面临着责任主体和索赔主体不明、过失作为例外要件存在不合理、国际保险标准难统一、责任分配制度待完善的困境。对此,可考虑通过关联性确认责任主体和索赔主体、对损害统一适用绝对责任、引入强制责任保险、形成双重责任制度,为国家载人航天商业化发展提供制度构建思路;同时,促进国际社会达成共识,推动人类命运共同体理念在外空领域的进一步实现。 展开更多
关键词 载人航天商业化 国际损害责任 外层空间法 空间物体 责任主体
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破孔面积对燃气弹射性能影响机理分析
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作者 王磊 郭保全 +2 位作者 朱家萱 黄通 高钦和 《固体火箭技术》 CAS CSCD 北大核心 2024年第2期285-292,共8页
为探究发射筒破损面积对燃气弹射过程的影响,采用RNG k-ε湍流模型、有限速率/涡耗散模型和动态分层网格技术,建立包含筒壁损伤的发射筒三维数值模型,在数值验证的基础上通过改变破孔直径,仿真得到不同破孔面积下发射筒内流场分布与内... 为探究发射筒破损面积对燃气弹射过程的影响,采用RNG k-ε湍流模型、有限速率/涡耗散模型和动态分层网格技术,建立包含筒壁损伤的发射筒三维数值模型,在数值验证的基础上通过改变破孔直径,仿真得到不同破孔面积下发射筒内流场分布与内弹道参数。结果表明:在发射筒内部整体流场形态近似呈对称分布,但由于燃气产生附壁效应和旋转涡的出现,局部流场呈现非对称性;随孔径增大筒内压力减小,孔径为160 mm时,t_(0)时速度相比完整筒壁的速度下降高达13.17%,在设定的出筒条件下当孔径大于140 mm后不能满足出筒要求;进行各参数相关性分析时发现破孔面积与第一次压力峰值及t_(0)时速度之间呈负线性相关。 展开更多
关键词 燃气弹射 发射筒破损面积 初容室 内流场 内弹道
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新城疫病毒La Sota株热损伤靶点的初步分析
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作者 曾敏倩 焦嘉杰 +7 位作者 左晓昕 王军宁 赵艳红 冯磊 卢宇 吕芳 周斌 侯继波 《中国家禽》 北大核心 2024年第2期59-67,共9页
为探索新城疫病毒不耐热毒株La Sota热损伤靶点,以期为新型耐热疫苗研发提供理论依据,试验通过检测加热前后La Sota株的吸附及内化功能,考察纤突蛋白HN和F活性变化情况,以及核衣壳完整性,综合分析新城疫病毒热损伤靶点。结果显示:37℃加... 为探索新城疫病毒不耐热毒株La Sota热损伤靶点,以期为新型耐热疫苗研发提供理论依据,试验通过检测加热前后La Sota株的吸附及内化功能,考察纤突蛋白HN和F活性变化情况,以及核衣壳完整性,综合分析新城疫病毒热损伤靶点。结果显示:37℃加热24 h后F蛋白活性首先受损,表现为内化功能显著下降(0.01<P<0.05),56℃加热15 min后HN和F蛋白活性几乎丧失,表现为吸附及内化功能均极显著下降(P<0.01);高温加热后,病毒核衣壳完整性显著降低,病毒粒子破损且失去纤突结构,表现为吸附及内化功能极显著下降(P<0.01)。研究表明,La Sota株热损伤靶点与加热温度和时间密切相关:中温下(≤56℃)病毒热损伤靶点主要在HN和F蛋白,高温下(≥80℃)病毒热损伤靶点为纤突蛋白和核衣壳;纤突蛋白的热敏感性高于核衣壳,且F蛋白受损早于HN蛋白。 展开更多
关键词 新城疫病毒 La Sota株 热损伤靶点 吸附 内化 纤突蛋白 核衣壳
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学生社会与情感能力:国际比较与中国表现 被引量:2
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作者 黄忠敬 唐一鹏 王娟 《华东师范大学学报(教育科学版)》 北大核心 2024年第5期33-57,共25页
OECD发布了最新第二轮学生社会与情感能力的全球测评结果,中国济南在其中的表现值得关注。本文基于SSES2023的学生数据,从国际比较的视角出发,对中国学生在社会与情感能力上的表现及其国际地位进行全方位的分析。基于全球各城市能力均... OECD发布了最新第二轮学生社会与情感能力的全球测评结果,中国济南在其中的表现值得关注。本文基于SSES2023的学生数据,从国际比较的视角出发,对中国学生在社会与情感能力上的表现及其国际地位进行全方位的分析。基于全球各城市能力均值分析的主要研究发现如下:(1)亚洲学生在社会与情感能力上表现突出。(2)济南10岁组学生在任务能力上居于全球首位,15岁组名列前茅,但成就动机得分稍低。(3)济南10岁组学生在情绪调节上居于全球前列,15岁组部分能力低于国际均值。(4)济南10岁组学生在协作能力上居于全球首位,15岁组居于前列。(5)济南10岁组学生在开放能力上的表现居于全球前列,15岁组低于国际均值。(6)济南10岁组学生在交往能力上居于全球首位,15岁组部分能力低于国际均值。基于社会与情感能力影响因素分析的主要研究发现如下:(1)济南学生在大部分影响因素指标上均优于国际均值,特别是同学关系方面居于全球首位。(2)影响济南学生任务能力的关键积极因素是成长型思维、师生关系、学校归属感和课外活动,其中学校归属感的影响效应居于全球首位。(3)影响济南学生情绪调节能力的关键因素是成长型思维、学校归属感和课外活动,其中学校归属感的影响居于全球首位。(4)影响济南学生协作能力的关键因素是成长型思维、同学关系、学校归属感和课外活动,其中成长型思维的影响效应居于全球首位。(5)影响济南学生开放能力的关键因素是成长型思维、学校归属感、课外活动和教师反馈,10岁组的学校归属感对部分开放能力的影响效应居于全球首位,15岁组的成长型思维对部分开放能力的影响效应相对偏低。(6)影响济南学生交往能力的关键因素是成长型思维、学校归属感和课外活动,其中学校归属感的影响效应在各个城市中居于前列。基于社会与情感能力对学生发展分析的主要研究发现如下:(1)济南学生的生活满意度居于全球首位,心理幸福感偏低。(2)乐观、信任、成就动机和抗压力是影响济南学生生活满意度的重要社会与情感能力。(3)乐观、信任和情绪控制是影响济南学生心理幸福感的重要社会与情感能力。(4)乐观和活力是影响济南学生健康行为的重要社会与情感能力。(5)情绪控制、抗压力和活力是影响济南学生学业焦虑的重要社会与情感能力。(6)乐观、信任和成就动机是影响济南学生关系满意度的重要社会与情感能力。(7)乐观、抗压力和果敢是影响济南学生身体意象的重要社会与情感能力。 展开更多
关键词 社会与情感能力 国际比较 中国表现
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多箱型结构内部爆炸破坏模式分析方法
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作者 李璐萌 张舵 +2 位作者 姚术健 黄诗麒 黄河 《北京理工大学学报》 EI CAS CSCD 北大核心 2024年第3期239-250,共12页
结构内部爆炸破坏是武器毁伤目标的主要方式之一,破坏模式和破坏范围是结构内部爆炸破坏威力的主要表征方式,其分析方法能够有力支撑武器毁伤效果预测和结构防护设计.采用有限元模拟仿真分析,研究多箱型结构内爆毁伤特性,基于仿真结果,... 结构内部爆炸破坏是武器毁伤目标的主要方式之一,破坏模式和破坏范围是结构内部爆炸破坏威力的主要表征方式,其分析方法能够有力支撑武器毁伤效果预测和结构防护设计.采用有限元模拟仿真分析,研究多箱型结构内爆毁伤特性,基于仿真结果,分析了破坏范围和破坏模式随当量和结构参数的变化规律,并提出了能够计算多箱型结构破坏范围、破坏壁面数和破坏分布模式的无量纲数和计算方法,绘制出破坏分布模式图和破坏范围表,该方法能够预测随爆炸当量非连续变化的破坏模式和破坏范围,并根据已有实验结果进行了验证. 展开更多
关键词 内部爆炸 破坏特性 破坏模式 量纲分析 多箱型结构
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水下滑坡运动诱导形成的内波特性及破坏分层特征
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作者 刘宗翰 姚烨 +2 位作者 练继建 陈亮 颜东谊 《人民黄河》 CAS 北大核心 2024年第4期105-110,共6页
为改善湖库因季节性水温分层而导致的水质恶化现象,通过水下滑坡体扰动的方式人工诱导产生内波,探究了水下滑坡运动诱导形成的内波特性及其对水体温度分层结构的破坏特征,结果表明:水下滑坡破坏水体温度分层结构主要通过扰动引起上下层... 为改善湖库因季节性水温分层而导致的水质恶化现象,通过水下滑坡体扰动的方式人工诱导产生内波,探究了水下滑坡运动诱导形成的内波特性及其对水体温度分层结构的破坏特征,结果表明:水下滑坡破坏水体温度分层结构主要通过扰动引起上下层水体交换实现,在此过程中内波作用效果持久且较为平缓;滑坡倾角和滑坡体运动速度对分层水体破坏效果有重要影响;滑坡倾角为45°工况相较60°工况诱导的内波规模更大。 展开更多
关键词 水体温度分层 分层水环境 水下滑坡 内波特性 分层破坏特征
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