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Chinese version of the Perth Alexithymia Questionnaire:psychometric properties and clinical applications
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作者 Xin-Lu Cai Qingying Ye +7 位作者 Ke Ni Lin Zhu Qian Zhang Minmin Yin Zhe Zhang Wei Wei David A.Preece Bao-Ming Li 《General Psychiatry》 CSCD 2024年第2期274-283,共10页
Background The alexithymia trait is of high clinical interest.The Perth Alexithymia Questionnaire(PAQ)was recently developed to enable detailed facet-level and valence-specific assessments of alexithymia.Aims In this ... Background The alexithymia trait is of high clinical interest.The Perth Alexithymia Questionnaire(PAQ)was recently developed to enable detailed facet-level and valence-specific assessments of alexithymia.Aims In this paper,we introduce the first Chinese version of the PAQ and examine its psychometric properties and clinical applications.Methods In Study 1,the PAQ was administered to 990 Chinese participants.We examined its factor structure,internal consistency,test-retest reliability,as well as convergent,concurrent and discriminant validity.In Study 2,four groups,including a major depressive disorder(MDD)group(n=50),a matched healthy control group for MDD(n=50),a subclinical depression group(n=50)and a matched healthy control group for subclinical depression(n=50),were recruited.Group comparisons were conducted to assess the clinical relevance of the PAQ.Results In Study 1,the intended five-factor structure of the PAQ was found to fit the data well.The PAQ showed good internal consistency and test-retest reliability,as well as good convergent,concurrent and discriminant validity.In Study 2,the PAQ was able to successfully distinguish the MDD group and the subclinical depression group from their matched healthy controls.Conclusions The Chinese version of the PAQ is a valid and reliable instrument for comprehensively assessing alexithymia in the general population and adults with clinical/subclinical depression. 展开更多
关键词 CLINICAL instrument matched
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Sustainable Water Management for Urban Agriculture, Gardens and Public Open Space Irrigation: A Case Study in Perth
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作者 Raju Sharma Dhakal Geoff Syme +1 位作者 Edward Andre Charles Sabato 《Agricultural Sciences》 2015年第7期676-685,共10页
Urban agriculture has been increasingly popular as a form of modern agriculture in urban settings. It includes community gardens, fruit orchards, home gardens, veggie patches, public open spaces, reserves, urban fores... Urban agriculture has been increasingly popular as a form of modern agriculture in urban settings. It includes community gardens, fruit orchards, home gardens, veggie patches, public open spaces, reserves, urban forest, and recreational landscaping. However, irrigation using urban water supply has been identified as a major constraints for the development of urban agriculture. This study presents a sustainable water management trial at Butler, a northern sub-urban development in Perth, Western Australia, for urban irrigation. The trial system consists of a number of water saving features including untreated fit-for-purpose groundwater supplied via a third pipe network, drip irrigation, local weather station, soil moisture sensors connected with a local weather station, night time irrigation, soil enhancement with conditioning and mulching, and use of native plants and vegetation. The trial outcome was compared against controlled areas in terms of irrigation efficiency and sustainable water management for urban agriculture. The study demonstrated that a fit-for-purpose irrigation along with water sensitive land management could be a sustainable alternative for urban agriculture that would achieve a significant water saving and irrigation efficiency at urban settings. However, quality of untreated groundwater can be an issue while utilizing it for irrigation, but the research has shown that it can be managed with innovative irrigation techniques. This indicates that the fit-for-purpose irrigation system with water sensitive land management practices would be highly supportive in sustainable development of urban agriculture, vegetation and recreational landscaping. 展开更多
关键词 URBAN AGRICULTURE SUSTAINABLE IRRIGATION System Integrated LAND and Water Management
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An Integrated Rock Typing Approach for Unraveling the Reservoir Heterogeneity of Tight Sands in the Whicher Range Field of Perth Basin, Western Australia
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作者 Rahim Kadkhodaie Ilkhchi Reza Rezaee +2 位作者 Reza Moussavi Harami Henrik Friis Ali Kadkhodaie Ilkhchi 《Open Journal of Geology》 2014年第8期373-385,共13页
Tight gas sands in Whicher Range Field of Perth Basin show large heterogeneity in reservoir characteristics and production behavior related to depositional and diagenetic features. Diagenetic events (compaction and ce... Tight gas sands in Whicher Range Field of Perth Basin show large heterogeneity in reservoir characteristics and production behavior related to depositional and diagenetic features. Diagenetic events (compaction and cementation) have severely affected the pore system. In order to investigate the petrophysical characteristics, reservoir sandstone facies were correlated with core porosity and permeability and their equivalent well log responses to describe hydraulic flow units and electrofacies, respectively. Thus, very tight, tight, and sub-tight sands were differentiated. To reveal the relationship between pore system properties and depositional and diagenetic characteristics in each sand type, reservoir rock types were extracted. The identified reservoir rock types are in fact a reflection of internal reservoir heterogeneity related to pore system properties. All reservoir rock types are characterized by a compacted fabric and cemented framework. But distribution and dominance of diagenetic products in each of them depend on primary depositional composition and texture. The results show that reservoir rock typing based on three aspects of reservoir sandstones (depositional properties, diagenetic features and petrophysical characteristics) is a suitable technique for depiction of reservoir heterogeneity, recognition of reservoir units and identifying factors controlling reservoir quality of tight sandstones. This methodology can be used for the other tight reservoirs. 展开更多
关键词 TIGHT SANDS Electorofacies Hydraulic Flow Unit ROCK Type RESERVOIR Characteristics
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久坐间断对成年人血管功能的急性影响与调节因素:荟萃分析
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作者 殷明越 刘骞 +4 位作者 许雄壮 马智英 邓盛基 邓鉴峰 黎涌明 《中国组织工程研究》 CAS 北大核心 2025年第17期3684-3696,共13页
目的:持续性地久坐行为会急性降低外周与中枢血管功能,进而加剧罹患心血管疾病风险。久坐间断可能是预防持续久坐对血管功能危害的潜在实用策略,但目前关于其急性功效的已有研究结论并不一致,也尚未得出具体的应用建议。文章旨在对久坐... 目的:持续性地久坐行为会急性降低外周与中枢血管功能,进而加剧罹患心血管疾病风险。久坐间断可能是预防持续久坐对血管功能危害的潜在实用策略,但目前关于其急性功效的已有研究结论并不一致,也尚未得出具体的应用建议。文章旨在对久坐间断对成人外周与中枢血管功能的急性影响进行荟萃分析,并探究其调节因素。方法:基于PRISMA报告规范,以“interrupting”“sedentary”与“vascular function”等为文献检索特征词,于2024年3月检索Web of Science核心合集、PubMed和中国知网数据库。纳入久坐间断对成人外周与中枢血管功能的急性影响的急性随机交叉试验文献。基于Cochrane开发的Risk of Bias 2评估偏倚风险,并基于GRADE系统评价证据等级。使用R语言(版本4.2.0)中的“meta”与“metafor”包进行主效应合并(Hedge’s g作为效应量指标)、发表偏倚检验、亚组与回归分析。结果:纳入22篇随机交叉试验,共364例受试者(年龄21-70岁)。相比于持续不间断久坐,久坐间断急性提升外周血管血流量(Hedge’s g=0.48,95%CI:0.14-0.82,P<0.01,I2=63%,低证据等级)、剪切应力(Hedge’s g=0.65,95%CI:0.37-0.93,P<0.01,I^(2)=54%,中等证据等级)与血流介导的血管舒张功能(Hedge’s g=0.43,95%CI:0.15-0.72,P<0.01,I2=61%,中等证据等级)。疾病(亚组间P=0.01)与性别(亚组间P=0.01)对血流量的主效应合并有显著调节作用(亚组间P=0.01),间断方式(亚组间P=0.01)与频率(亚组间P=0.02)对剪切应力的主效应合并有显著调节作用。久坐间断改善外周血管剪切应力受年龄(β=-0.02,95%CI:-0.03-0.01,P=0.09)与体质量指数(β=-0.10,95%CI:-0.18至-0.02,P<0.01)影响。久坐间断改善血流介导的血管舒张功能受总间断次数(β=-0.09,95%CI:-0.17至-0.01,P=0.03)与试验期间久坐控制时长影响(β=-0.21,-0.34至-0.09,P<0.01);每增加1 h久坐时长与久坐间断对血流介导的血管舒张功能的急性提升效果降低0.67%相关(P<0.01),当久坐控制时间>6 h时,久坐间断的急性收益消失。定性系统综述发现,久坐间断对各类人群血管脉搏波速度无显著影响,但可能预防老年人因持续久坐引起的中枢血管功能下降。结论:久坐间断急性提升成人外周血管血流量(低证据强度)、剪切应力(中证据强度)与血流介导的血管舒张功能(中证据强度),并可能预防、保护老年人因持续久坐引起的中枢血管功能下降(非常低证据等级)。受试者特征(疾病因素、性别、年龄与体质量指数)、间断干预方案(方式、频率、总间断次数)与久坐控制时长均会影响久坐间断对血管功能的急性改善效果。建议各类成人通过爬楼等大肌肉群参与的运动方式,以较高频率(如,每40 min进行1次)进行单次至少5 min的中低强度运动间断久坐,且每日持续久坐的累积时长不要超过6 h。 展开更多
关键词 久坐间断 久坐行为 碎片化运动 血流介导的血管舒张功能 血管功能 血流量 剪切应力 中枢血管功能 荟萃分析 Meta分析
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Catalyst–Support Interaction in Polyaniline‑Supported Ni_(3)Fe Oxide to Boost Oxygen Evolution Activities for Rechargeable Zn‑Air Batteries
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作者 Xiaohong Zou Qian Lu +8 位作者 Mingcong Tang Jie Wu Kouer Zhang Wenzhi Li Yunxia Hu Xiaomin Xu Xiao Zhang Zongping Shao Liang An 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期176-190,共15页
Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3... Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3)Fe oxide/PANI)with a robust hetero-interface,which significantly improves oxygen evolution activities with an overpotential of 270 mV at 10 mA cm^(-2)and specific activity of 2.08 mA cm_(ECSA)^(-2)at overpotential of 300 mV,3.84-fold that of Ni_(3)Fe oxide.It is revealed that the catalyst–support interaction between Ni_(3)Fe oxide and PANI support enhances the Ni–O covalency via the interfacial Ni–N bond,thus promoting the charge and mass transfer on Ni_(3)Fe oxide.Considering the excellent activity and stability,rechargeable Zn-air batteries with optimum Ni_(3)Fe oxide/PANI are assembled,delivering a low charge voltage of 1.95 V to cycle for 400 h at 10 mA cm^(-2).The regulation of the effect of catalyst–support interaction on catalytic activity provides new possibilities for the future design of highly efficient OER catalysts. 展开更多
关键词 Catalyst-support interaction Supported catalysts HETEROINTERFACE Oxygen evolution reaction Zn-air batteries
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非线性块系岩体动力响应及在巷道防冲支护中的应用 被引量:3
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作者 姜宽 戚承志 《力学学报》 EI CAS CSCD 北大核心 2024年第4期1057-1067,共11页
随着煤矿开采深度的增加,冲击地压灾害日趋严重,亟需采用新方法、新理论加以防治.摆型波是在深部岩体工程中发现的新型非线性波,其使岩体出现相对分离和相对压实的不同运动状态,与冲击地压灾害的发生密切相关.针对岩体中软弱结构层的非... 随着煤矿开采深度的增加,冲击地压灾害日趋严重,亟需采用新方法、新理论加以防治.摆型波是在深部岩体工程中发现的新型非线性波,其使岩体出现相对分离和相对压实的不同运动状态,与冲击地压灾害的发生密切相关.针对岩体中软弱结构层的非线性变形特征,引入双曲线模型建立块系岩体中摆型波传播的非线性动力模型,研究软弱层的物理力学性质(最大闭合量、初始刚度和阻尼)对块系岩体动力响应的影响.进一步,基于块系围岩与支护系统互馈作用的理论模型,在无初始地应力和考虑初始地应力的情况下研究巷道支护系统的刚度、让位能力和阻尼耗能作用对巷道顶板动力响应的影响,分析支护系统的受力情况,为新型防冲吸能巷道液压支架设备的吸能让位行为提供理论依据.研究结果表明:基于双曲线模型建立的块系岩体的非线性动力模型能够限制岩块间软弱层的最大变形量.冲击载荷越大,增大软弱层最大闭合量时岩块的加速度降低程度越显著.增加支护系统刚度,增强支护系统让位能力和阻尼耗能能力,均可有效降低巷道顶板的加速度幅值,减轻巷道围岩对支护系统的冲击力,有效保护巷道结构. 展开更多
关键词 块系岩体 摆型波 双曲线模型 冲击地压 巷道支护 初始地应力
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中国灵长类动物保护的成就与挑战
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作者 李保国 张河 +21 位作者 李明 蒋学龙 范朋飞 周江 郭松涛 齐晓光 李进华 路纪琪 夏东坡 崔亮伟 向左甫 周岐海 黄志旁 黄乘明 肖文 胡慧建 周智鑫 陈明勇 黎大勇 范朋来 杨寅 潘汝亮 《西北大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第5期755-766,共12页
气候变化和人类活动的双重影响导致全球灵长类生物多样性急剧下降。中国是北半球灵长类动物种类最多的国家,但在农业社会向现代社会转型的过程中,现代农业的扩张、自然资源的消耗以及土地的过度开发,使中国面临着严重的生态威胁。为此,... 气候变化和人类活动的双重影响导致全球灵长类生物多样性急剧下降。中国是北半球灵长类动物种类最多的国家,但在农业社会向现代社会转型的过程中,现代农业的扩张、自然资源的消耗以及土地的过度开发,使中国面临着严重的生态威胁。为此,中国实施了包括栖息地恢复和保护在内的多种生态保护措施,在生物多样性保护方面取得了实质性进展,某些地区的灵长类动物种群数量有所增加。该研究对中国灵长类动物的历史文献和实地调查资料进行了系统分析,对中国灵长类动物的濒危状况进行了评估。尽管大多数灵长类物种的栖息地有所改善,种群数量也有所增长,但许多物种仍然面临着严重的威胁,包括种群数量的减少。例如,缅甸金丝猴、东黑冠长臂猿和海南长臂猿等物种由于分布范围有限和种群数量极少,仍然特别脆弱。科学数据的缺乏以及保护生物学研究的不足,进一步加剧了这些挑战。此外,蜂猴、倭蜂猴、印支灰叶猴、肖氏乌叶猴和戴帽叶猴等物种的详细种群监测数据仍然缺乏,这严重阻碍了针对这些物种保护管理政策的制定。因此,在生物多样性保护方面,迫切需要开展专门的灵长类动物调查,实行跨境保护和区域合作,建立全面系统的数据库平台,对灵长类生物学进行持续深入的研究。此外,加强公众对野生动物保护的认识也至关重要。这些综合、系统的工作将为中国灵长类物种的保护和管理提供科学依据。 展开更多
关键词 灵长类动物 生物多样性 栖息地破碎化 生境修复 保护策略
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宁夏不同草地类型土壤微生物残体碳积累特征及其影响因素
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作者 马进鹏 吴梦瑶 +4 位作者 张雅琪 庞丹波 陈林 李学斌 陈应龙 《生态学报》 CAS CSCD 北大核心 2024年第20期9300-9313,共14页
为探究不同草地类型土壤微生物残体碳积累特征,明确微生物残体碳对土壤有机碳(SOC)的贡献及影响因素。研究利用生物标记物的方法,测定宁夏草甸草原(MS)、典型草原(TS)、荒漠草原(DS)、草原化荒漠(SD)和荒漠(D)5种草地类型0—20 cm土壤... 为探究不同草地类型土壤微生物残体碳积累特征,明确微生物残体碳对土壤有机碳(SOC)的贡献及影响因素。研究利用生物标记物的方法,测定宁夏草甸草原(MS)、典型草原(TS)、荒漠草原(DS)、草原化荒漠(SD)和荒漠(D)5种草地类型0—20 cm土壤的理化性质、微生物群落组成及氨基糖含量,进一步分析微生物残体碳含量与土壤理化性质和微生物群落的关系。结果表明:MS和TS土壤有机碳、全氮、铵态氮、硝态氮、微生物量碳、微生物量氮、真菌、细菌、放线菌和原生动物含量显著高于其他草地类型(P<0.05)。土壤氨基葡萄糖(GluN)、氨基甘露糖(ManN)、氨基半乳糖(GalN)和胞壁酸(MurA)含量均表现为MS最大,D最小(P<0.05);不同草地类型土壤氨基葡萄糖含量((0.62±0.18)μg/mg)最高,胞壁酸含量((0.04±0.01)μg/mg)最低。不同草地类型土壤细菌残体碳(BNC)、真菌残体碳(FNC)和总残体碳(TNC)变化范围为0.12—5.74μg/mg、0.22—15.31μg/mg和0.34—21.05μg/mg;BNC、FNC和TNC对SOC贡献分别为9.0%—17.8%、22.0%—48.2%和33.5%—66.0%;FNC对SOC的贡献是BNC的1.8—3.8倍。相关性分析显示,微生物残体碳含量与海拔、年降雨量、干旱指数、地上生物量、地下生物量以及土壤有机碳、全氮、铵态氮、硝态氮、全磷、微生物生物量(微生物量碳、微生物量氮、微生物量磷、真菌、细菌、放线菌和原生动物)显著正相关(P<0.05),与年均温及土壤容重、pH显著负相关(P<0.05)。细菌残体碳和真菌残体碳含量分别随细菌和真菌含量的增大而增大(P<0.001),微生物残体碳含量随真菌/细菌值的增大而增大(P<0.05),随革兰氏阳性/革兰氏阴性细菌(GP/GN)值的增大而减小(P<0.01)。随机森林模型预测显示,土壤全氮和pH是土壤微生物残体碳的主要影响因子。研究分析了宁夏不同草地类型微生物来源有机碳的积累特征及影响因素,可为进一步探讨干旱半干旱草地生态系统土壤有机碳固存的微生物学机制提供数据支撑。 展开更多
关键词 草地类型 氨基糖 微生物残体 土壤有机碳 生物标志物
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Making wheat salt tolerant:What is missing? 被引量:1
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作者 Lukasz Kotula Noreen Zahra +2 位作者 Muhammad Farooq Sergey Shabala Kadambot H.M.Siddique 《The Crop Journal》 SCIE CSCD 2024年第5期1299-1308,共10页
The growing global population presents a significant challenge to ensuring food security,further compounded by the increasing threat of salinity to agricultural productivity.Wheat,a major staple food providing 20%of t... The growing global population presents a significant challenge to ensuring food security,further compounded by the increasing threat of salinity to agricultural productivity.Wheat,a major staple food providing 20%of the total caloric intake for humans,is susceptible to salinity stress.Developing new salttolerant wheat cultivars using wheat breeding techniques and genetic modifications is crucial to addressing this issue while ensuring the sustainability and efficiency of wheat production systems within the prevailing climate trend.This review overviews the current landscape in this field and explores key mechanisms and associated genetic traits that warrant attention within breeding programs.We contend that traditional approaches to breeding wheat for Na^(+)exclusion have limited applicability across varying soil salinity levels,rendering them inefficient.Moreover,we question current phenotyping approaches,advocating for a shift from whole-plant assessments to cell-based phenotyping platforms.Finally,we propose a broader use of wild wheat relatives and various breeding strategies to tap into their germplasm pool for inclusion in wheat breeding programs. 展开更多
关键词 PHENOTYPING BREEDING Reactive oxygen species Tissue tolerance Sodium exclusion Potassium retention
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基于固体声弹理论的地震反射透射研究进展
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作者 陈阜斌 宗兆云 印兴耀 《地球与行星物理论评(中英文)》 2024年第3期344-357,共14页
多期沉积埋深及成岩过程使地下储层介质具有复杂初始地应力,应力范围跨度大且分布方向复杂.初始地应力对储层介质岩石物理与地震波传播响应具有显著影响.地震反射透射系数方程可以量化储层性质与地球物理观测数据的关系,构建考虑初始地... 多期沉积埋深及成岩过程使地下储层介质具有复杂初始地应力,应力范围跨度大且分布方向复杂.初始地应力对储层介质岩石物理与地震波传播响应具有显著影响.地震反射透射系数方程可以量化储层性质与地球物理观测数据的关系,构建考虑初始地应力作用的地震反射透射系数方程有利于更好理解深部储层界面处地震波传播特征,为深层油气勘探奠定理论基础,正逐渐受到国内外学者的关注.当前已提出的相关理论模型主要从固体声弹理论出发,考虑初始应力与地震波扰动引起的微小固体应变,聚焦岩石物理与地震反射透射参数化的理论方法研究,在应力诱导各向异性参数反演、地应力预测、油气储层识别等方面开展了初步实际应用探索.本文首先介绍固体声弹理论核心内容,然后介绍了基于声弹理论的地震反射透射模型、基本假设及其阶段性应用进展,讨论了方程的局限性以及在地震勘探领域的发展方向. 展开更多
关键词 地震反射透射系数 固体声弹理论 初始地应力 深部储层
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Optimizing the Bacillus thuringiensis(Bt)protein concentration in cotton:Coordinated application of exogenous amino acids and EDTA to reduce spatiotemporal variability in boll and leaf toxins 被引量:1
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作者 Zhenyu Liu Shu Dong +8 位作者 Yuting Liu Hanjia Li Fuqin Zhou Junfeng Ding Zixu Zhao Yinglong Chen Xiang Zhang Yuan Chen Dehua Chen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3419-3436,共18页
During the boll formation stage,cotton bolls exhibit the lowest expression of Bacillus thuringiensis(Bt)insecticidal proteins.Resistance to insects varies notably among different organs,which poses challenges for cont... During the boll formation stage,cotton bolls exhibit the lowest expression of Bacillus thuringiensis(Bt)insecticidal proteins.Resistance to insects varies notably among different organs,which poses challenges for controlling cotton bollworms.Consequently,an experimental strategy was designed in the 2020-2021 cotton growing season to coordinate the enhancement of protein synthesis and the attenuation of degradation.Two Bt cultivars of Gossypium hirsutum,namely the hybrid Sikang 3 and the conventional Sikang 1,were used as test materials.Three treatments were applied at the peak flowering period:CK(the control),T1(amino acids),and T2(amino acids and EDTA).The results show that,in comparison to the CK group,the Bt protein contents were significantly increased in both cotton bolls and their subtending leaves under the T1 and T2 treatments.The maximum levels of increase observed were 67.5%in cotton bolls and 21.7%in leaves.Moreover,the disparity in Bt protein content between cotton bolls and their subtending leaves notably decreased by 31.2%.Correlation analysis suggested that the primary physiological mechanisms for augmenting Bt protein content involve increased protein synthesis and reduced protein catabolism,which are independent of Bt gene expression levels.Stepwise regression and path analysis revealed that elevating the soluble protein content and transaminase activity,while reducing the catabolic enzyme activities,are instrumental in enhancing the Bt protein content.Consequently,the coordinated application of amino acids and EDTA emerges as a strategy that can improve the overall resistance of Bt cotton and mitigate the spatiotemporal variations in Bt toxin concentrations in both cotton bolls and leaves. 展开更多
关键词 Gossypium hirsutum Bt cotton insecticidal protein bolls and their subtending leaves nitrogen metabolism
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PZT基多层剪切型压电陶瓷致动器驱动性能
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作者 王振宇 王世杰 +4 位作者 王鹏 张东雷 郭明楷 秦国帅 卢春生 《微纳电子技术》 CAS 2024年第12期97-105,共9页
随着驱动技术向微型化与高精度化方向发展,压电致动器因其在精确位移控制和快速响应方面的优势而受到广泛关注。提出了一种基于锆钛酸铅(PZT)陶瓷的多层剪切型压电致动器,并采用有限元分析方法及自主开发的新型实验平台对其驱动性能进... 随着驱动技术向微型化与高精度化方向发展,压电致动器因其在精确位移控制和快速响应方面的优势而受到广泛关注。提出了一种基于锆钛酸铅(PZT)陶瓷的多层剪切型压电致动器,并采用有限元分析方法及自主开发的新型实验平台对其驱动性能进行深入研究。结果表明,致动器的驱动性能主要受输入电压频率和幅值的影响,在适当的频率与低电压条件下可实现更高的调控分辨率。此外,当结构施加的预紧力超过最大负载时,致动器的驱动性能下降约50%,即通过预紧力可有效调控致动器的驱动性能,该结果为压电致动器的工作模式分析以及多层压电陶瓷的电学结构优化提供了重要的依据。 展开更多
关键词 压电致动器 锆钛酸铅(PZT) 多层剪切型 驱动性能 微型化
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基于深度学习的3D打印混凝土蒸汽养护力学性能研究和抗压强度预测 被引量:1
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作者 孙浚博 王雨飞 +1 位作者 赵宏宇 王翔宇 《硅酸盐通报》 CAS 北大核心 2024年第5期1723-1738,1783,共17页
3D打印混凝土(3DCP)技术近年来获得广泛关注,然而,关于养护条件如何影响3DCP的力学性能的研究仍然较少。本研究主要探讨不同蒸汽养护条件(升温速率、恒温时间和恒温温度)对3D打印混凝土材料的力学性能影响规律。为了获得最佳蒸汽养护条... 3D打印混凝土(3DCP)技术近年来获得广泛关注,然而,关于养护条件如何影响3DCP的力学性能的研究仍然较少。本研究主要探讨不同蒸汽养护条件(升温速率、恒温时间和恒温温度)对3D打印混凝土材料的力学性能影响规律。为了获得最佳蒸汽养护条件,通过正交试验研究了不同蒸汽养护条件下打印胶凝材料的力学各向异性。此外,基于室内试验数据,建立了条件表格生成对抗网络(CTGAN)用于扩充数据集,由291条数据扩充为1000条数据,建立了一维残差卷积神经网络(1D-Residual CNN)用于预测3DCP的抗压强度,并建立了5个机器学习(ML)模型用于对比,试验结果表明,CTGAN的数据增强技术可以有效提升1D-Residual CNN模型在3DCP抗压强度上的预测精度,R2最高为0.92。 展开更多
关键词 3D打印混凝土 蒸汽养护 各向异性 抗压强度 深度学习 生成对抗网络
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小反刍兽疫免疫抗体监测的Meta分析
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作者 王艺 沈鹏 +6 位作者 钱莺娟 蔡畅 常星 韩秀琚 徐蛟 郑龙三 王志亮 《畜牧与兽医》 CAS 北大核心 2024年第11期100-108,共9页
小反刍兽疫(PPR)是我国计划要消灭的重大外来动物疫病,对于实施疫苗免疫预防的省份或地区,必须确保免疫覆盖率和免疫抗体合格率,才能有效阻断病毒的传播。我国在春防、秋防期间,会组织开展免疫抗体监测活动,对抗体水平不高的场户及时开... 小反刍兽疫(PPR)是我国计划要消灭的重大外来动物疫病,对于实施疫苗免疫预防的省份或地区,必须确保免疫覆盖率和免疫抗体合格率,才能有效阻断病毒的传播。我国在春防、秋防期间,会组织开展免疫抗体监测活动,对抗体水平不高的场户及时开展补免工作。为综合评价PPR的群体免疫情况,利用荟萃(Meta)分析方法对已发表的文献进行了梳理分析。通过关键词匹配和全文阅读,共有59篇文献符合要求纳入分析,包含样品252048份,抗体平均阳性率为85%(95%CI:83%~87%)。通过进行亚组分析和Wilcoxon显著性检验,发现山东省和江苏省的抗体阳性率明显高于其余省份;不同场户类型之间,规模场的抗体阳性率明显高于散养户;不同检测方法之间抗体阳性率无显著性差异。本研究的分析结果为PPR根除计划的实施提供了科学依据。 展开更多
关键词 小反刍兽疫 免疫 抗体 META分析
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Exercise training mode effects on myokine expression in healthy adults:A systematic review with meta-analysis 被引量:1
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作者 Francesco Bettariga Dennis R.Taaffe +6 位作者 Daniel A.Galvao Pedro Lopez Chris Bishop Anna Maria Markarian Valentina Natalucci Jin-Soo Kim Robert U.Newton 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第6期764-779,共16页
Background:The benefits of exercise are well known;however,many of the underlying molecular mechanisms are not fully understood.Skeletal muscle secretes myokines,which mediate muscleorgan crosstalk.Myokines regulate s... Background:The benefits of exercise are well known;however,many of the underlying molecular mechanisms are not fully understood.Skeletal muscle secretes myokines,which mediate muscleorgan crosstalk.Myokines regulate satellite-cell proliferation and migration,inflammatory cascade,insulin secretion,angiogenesis,fatty oxidation,and cancer suppression.To date,the effects of different exercise modes(namely,aerobic and resistance exercise)on myokine response remain to be elucidated.This is crucial considering the clinical implementation of exercise to enhance general health and wellbeing and as a medical treatment.Methods:A systematic search was undertaken in PubMed,MEDLINE,CINAHL,Embase,SPORTDiscus,andWeb of Science in April 2023.Eligible studies examining the effects of a single bout of exercise on interleukin15(IL-15),irisin,secreted protein acidic and rich in cysteine(SPARC),oncostatinM(OSM),and decorin were included.A random-effects meta-analysis was also undertaken to quantify the magnitude of change.Results:Sixty-two studies were included(n=1193).Overall,exercise appeared to induce small to large increases in myokine expression,with effects observed immediately after to 60 min post-exercise,although these were mostly not statistically significant.Both aerobic and resistance exercise resulted in changes in myokine levels,without any significant difference between training modes,and with the magnitude of change differing across myokines.Myokine levels returned to baseline levels within 180 min to 24 h post-exercise.However,owing to potential sources of heterogeneity,most changes were not statistically significant,indicating that precise conclusions cannot be drawn.Conclusion:Knowledge is limited but expanding with respect to the impact of overall and specific effects of exercise on myokine expression at different time points in the systemic circulation.Further research is required to investigate the effects of different exercise modes at multiple time points on myokine response. 展开更多
关键词 MYOKINE Resistance exercise Aerobic exercise CYTOKINE Systemic circulation
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西昆仑大红柳滩地区花岗岩类侵位时代与成因
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作者 庹明洁 夏永旗 +5 位作者 李诺 加娜提古丽·吾斯曼 于杰 祁冬梅 李婷 邰宗尧 《矿床地质》 CAS CSCD 北大核心 2024年第2期265-288,I0001-I0012,共36页
西昆仑大红柳滩地区花岗岩类分布广泛,与伟晶岩型锂(铍)矿化时空关系密切。为了约束其地质特征、岩石成因以及对伟晶岩型锂(铍)成矿的作用,文章对白龙山闪长岩、俘虏沟闪长岩和大红柳滩二云母花岗岩进行了岩石学、矿物学、地球化学和年... 西昆仑大红柳滩地区花岗岩类分布广泛,与伟晶岩型锂(铍)矿化时空关系密切。为了约束其地质特征、岩石成因以及对伟晶岩型锂(铍)成矿的作用,文章对白龙山闪长岩、俘虏沟闪长岩和大红柳滩二云母花岗岩进行了岩石学、矿物学、地球化学和年代学研究工作。地球化学数据揭示白龙山闪长岩和俘虏沟闪长岩明显富MgO、CaO和TiO_(2),属于准铝质-弱过铝质、高钾钙碱性岩浆系列,结合已有全岩Sr-Nd、锆石Lu-Hf等同位素数据,白龙山闪长岩和俘虏沟闪长岩涉及新生地壳的贡献,其源区贫黏土,可能以砂屑岩为主。全岩锆饱和温度计约束岩浆温度分别为762~795℃(平均781℃)和769~773℃(平均771℃)。角闪石温压计约束白龙山闪长岩中角闪石结晶温度为718~760℃(平均734℃),压力介于125~208 MPa之间(平均151 MPa);俘虏沟闪长岩中的角闪石结晶温度为729~776℃(平均741℃),压力介于133~231 MPa之间(平均176 MPa)。白龙山闪长岩和俘虏沟闪长岩锆石LA-ICP-MS U-Pb年龄分别为(213.67±0.61)Ma(MSWD=1.4,n=39)和(211.73±1.02)Ma(MSWD=1.9,n=14)。大红柳滩二云母花岗岩中发育电气石、白云母和石榴子石等富铝矿物,明显富SiO_(2)和K_(2)O,贫MgO、CaO和TiO_(2),属于过铝质、高钾钙碱性岩浆系列,由壳源物质重熔而成,源区可能是泥质岩。全岩锆饱和温度计约束其温度为755~773℃(平均764℃)。所含锆石往往发育继承核,其年龄介于207~2490 Ma之间。最年轻的岩浆锆石约束岩浆侵位可能发生在(211.20±1.1)Ma(MSWD=0.34,n=10),这些岩浆锆石随后被热液增生边包裹,U-Pb年龄约束岩浆-热液事件发生在(185.10±0.89)Ma(MSWD=4,n=5),可能记录了后期伟晶岩侵位所诱发的热液活动。大红柳滩地区同时发育I型和S型花岗岩,形成于中温(734~781℃)、中压(151~176 MPa)的条件,岩浆-热液活动持续时间长达~33 Ma,为形成超大型规模矿床提供有利条件。 展开更多
关键词 锆石U-PB年龄 岩石成因 花岗岩类 大红柳滩 西昆仑
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破膜压力对综合管廊燃气爆炸传播的影响
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作者 龙渊腾 戚承志 +1 位作者 卢春生 王泽帆 《北京建筑大学学报》 2024年第5期38-46,共9页
综合管廊应用广泛,泄漏燃气爆炸会对管廊造成严重破坏。利用燃气舱内潜在的泄爆体系,可降低爆炸冲击带来的危害,但是目前还缺乏这方面的定量研究。针对地下综合管廊中爆炸传播过程,利用Fluent软件建立了三维数值模型,模拟了不同破膜压... 综合管廊应用广泛,泄漏燃气爆炸会对管廊造成严重破坏。利用燃气舱内潜在的泄爆体系,可降低爆炸冲击带来的危害,但是目前还缺乏这方面的定量研究。针对地下综合管廊中爆炸传播过程,利用Fluent软件建立了三维数值模型,模拟了不同破膜压力下火焰传播、爆炸超压、爆炸超温的变化情况。结果表明:随着破膜压力增加,舱内火焰最大传播速度、最大爆炸超压、最大初始温度逐渐增加,火焰在燃气舱内持续的时间增加、泄爆口处火焰速度减缓;当破膜压力小于60 kPa时,舱内最大超压为燃烧混合物泄放产生的峰值;当大于60 kPa时,外部爆炸的气体不足以阻碍内部已燃气体的泄放,舱内最大爆炸超压为二次爆炸产生的峰值。泄爆可以延缓并降低首次爆炸超温峰值的出现。研究结果将有助于深入了解泄爆作用下综合管廊内燃气爆炸的传播规律以及为燃气舱内逃生口的设计提供参考。 展开更多
关键词 破膜压力 燃气舱 泄爆 爆炸传播 抑爆效果
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数字时代下旅游企业的人力资源供求与管理 被引量:2
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作者 李明龙 吕庚浩 +6 位作者 刘晶瑜 孙晓洋 李军 张慧英 黄丽满 黄松山 董诺 《旅游导刊》 2024年第2期1-24,共24页
旅游企业长期面临人力资源短缺、人才流失等困境,主要缘于其外部市场劳动力供需匹配出错、内部岗位设置与人力资源管理简单粗放。科技的数字化发展为解决上述问题提供了机遇,也提出了新的挑战。主要表现为:(1)数字时代塑造了旅游新场景... 旅游企业长期面临人力资源短缺、人才流失等困境,主要缘于其外部市场劳动力供需匹配出错、内部岗位设置与人力资源管理简单粗放。科技的数字化发展为解决上述问题提供了机遇,也提出了新的挑战。主要表现为:(1)数字时代塑造了旅游新场景、催生了旅游新需求,这也使旅游企业劳动力需求特征与技能结构发生了转变,旅游从业者需具备数字化的管理、分析、创新、服务、学习能力。(2)数字技术(如智能机器、大数据分析)正在重塑旅游服务分工与服务职能,可以通过系统支持、人机协作等方式增强员工工作能力,并在部分领域代替人类员工进行工作(尤其在程序化重复劳动方面),其应用面广泛、能力强大,对许多领域都有结构性的影响。旅游企业人力资源管理须关注旅游数字化转型中潜在的数字鸿沟和数字公平问题,确保数字技术的智慧化和便捷化能够平等地惠及每个利益群体。(3)数字技术使得用工更加灵活,在新的工作安排、新的工作性质、新的工人地位3个方面改变了灵活用工的形态。在数字时代,需要通过深化灵活用工平台治理、完善劳动者权益保障体系等措施,优化旅游企业的灵活用工管理。(4)数字时代,旅游企业的内部人力资源管理面临责任归属、数字能力提升、数据安全保护、客户隐私保护等多方面挑战,也带来了在人才识别与招聘、培训、绩效管理、员工关系和职工保留等多方面进行提升的新机遇。数字时代下,旅游企业人力资源经理必须弥合技术与人性之间的差距,注意数字技术应用带来的道德困境,并采取开放、适应的思维方式。(5)数字技术还可以赋能旅游企业劳动力的市场以实现供需匹配,即通过信息化变革使旅游企业劳动力供需数量达到动态平衡,通过知识化完善劳动力供需结构,通过平台化推动劳动力供需双方链接。 展开更多
关键词 数字技术 旅游企业 人力资源管理 劳动力供需匹配 员工技能结构
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Adaptive Trajectory Tracking Control for Nonholonomic Wheeled Mobile Robots:A Barrier Function Sliding Mode Approach 被引量:1
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作者 Yunjun Zheng Jinchuan Zheng +3 位作者 Ke Shao Han Zhao Hao Xie Hai Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期1007-1021,共15页
The trajectory tracking control performance of nonholonomic wheeled mobile robots(NWMRs)is subject to nonholonomic constraints,system uncertainties,and external disturbances.This paper proposes a barrier function-base... The trajectory tracking control performance of nonholonomic wheeled mobile robots(NWMRs)is subject to nonholonomic constraints,system uncertainties,and external disturbances.This paper proposes a barrier function-based adaptive sliding mode control(BFASMC)method to provide high-precision,fast-response performance and robustness for NWMRs.Compared with the conventional adaptive sliding mode control,the proposed control strategy can guarantee that the sliding mode variables converge to a predefined neighborhood of origin with a predefined reaching time independent of the prior knowledge of the uncertainties and disturbances bounds.Another advantage of the proposed algorithm is that the control gains can be adaptively adjusted to follow the disturbances amplitudes thanks to the barrier function.The benefit is that the overestimation of control gain can be eliminated,resulting in chattering reduction.Moreover,a modified barrier function-like control gain is employed to prevent the input saturation problem due to the physical limit of the actuator.The stability analysis and comparative experiments demonstrate that the proposed BFASMC can ensure the prespecified convergence performance of the NWMR system output variables and strong robustness against uncertainties/disturbances. 展开更多
关键词 Adaptive sliding mode barrier function nonholonomic wheeled mobile robot(NWMR) trajectory tracking control
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Towards Blockchain-Based Secure BGP Routing,Challenges and Future Research Directions 被引量:1
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作者 Qiong Yang Li Ma +3 位作者 Shanshan Tu Sami Ullah MuhammadWaqas Hisham Alasmary 《Computers, Materials & Continua》 SCIE EI 2024年第5期2035-2062,共28页
Border Gateway Protocol(BGP)is a standard inter-domain routing protocol for the Internet that conveys network layer reachability information and establishes routes to different destinations.The BGP protocol exhibits s... Border Gateway Protocol(BGP)is a standard inter-domain routing protocol for the Internet that conveys network layer reachability information and establishes routes to different destinations.The BGP protocol exhibits security design defects,such as an unconditional trust mechanism and the default acceptance of BGP route announcements from peers by BGP neighboring nodes,easily triggering prefix hijacking,path forgery,route leakage,and other BGP security threats.Meanwhile,the traditional BGP security mechanism,relying on a public key infrastructure,faces issues like a single point of failure and a single point of trust.The decentralization,anti-tampering,and traceability advantages of blockchain offer new solution ideas for constructing secure and trusted inter-domain routing mechanisms.In this paper,we summarize the characteristics of BGP protocol in detail,sort out the BGP security threats and their causes.Additionally,we analyze the shortcomings of the traditional BGP security mechanism and comprehensively evaluate existing blockchain-based solutions to address the above problems and validate the reliability and effectiveness of blockchain-based BGP security methods in mitigating BGP security threats.Finally,we discuss the challenges posed by BGP security problems and outline prospects for future research. 展开更多
关键词 BGP security blockchain prefix hijacking trust model secure routing
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