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用户视角下的教育数据要素交易:安全感知与建议

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苏州大学学报（教育科学版） 2024年第1期12卷 76-86页

作者：杨现民周丽华李新江苏师范大学江苏省教育信息化工程技术研究中心江苏徐州221116

教育数据要素作为推动教育变革的核心动力,正通过数据要素市场交易推动教育数字化转型纵深发展。然而,目前教育数据要素市场在数据确权、市场监督以及市场交易等制度层面存在不足,阻碍教育数据要素价值的释放。用户作为数据要素市场的... 详细信息

教育数据要素作为推动教育变革的核心动力,正通过数据要素市场交易推动教育数字化转型纵深发展。然而,目前教育数据要素市场在数据确权、市场监督以及市场交易等制度层面存在不足,阻碍教育数据要素价值的释放。用户作为数据要素市场的核心参与者,其对教育数据要素交易的安全感知与建议是推进数据要素交易有序发展的重要因素。研究面向四类不同用户群体开展了定向调查,发现用户总体对教育数据要素交易持积极态度,且具有较为全面的安全感知,不同用户群体则在教育数据要素基本态度、安全感知与安全建议上存在差异。为加快教育数据要素交易市场建设,可以从加强教育数据要素市场保障,提高高等院校用户市场参与意愿,构建教育数据要素安全体系,满足不同用户群体的安全需求,塑造多元教育数据要素交易市场,推动交易机制向需求侧转型等方面改善。

关键词：教育数据要素数据要素市场用户视角安全感知安全建议

牲畜饲养结构的时空分布特征及驱动因素——以宁夏为例

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草业学报 2024年第8期33卷 37-49页

作者：张聪王娅周立华裴孝东李军豪石贵中国科学院科技战略咨询研究院北京100190 中国科学院西北生态环境资源研究院甘肃兰州730000 中国科学院大学公共政策与管理学院北京100049

畜牧业是关系国计民生的重要产业,对于经济、环境以及食物安全都有重要意义。近年来,我国畜牧业总产出呈不断增长态势,但仍处于“大而不强,多而不优”的困境之中。本研究以牲畜饲养结构为对象,探究其时空分布特征和驱动因素,对畜牧业合... 详细信息

畜牧业是关系国计民生的重要产业,对于经济、环境以及食物安全都有重要意义。近年来,我国畜牧业总产出呈不断增长态势,但仍处于“大而不强,多而不优”的困境之中。本研究以牲畜饲养结构为对象,探究其时空分布特征和驱动因素,对畜牧业合理布局以及可持续发展有重要价值。首先分析了宁夏牲畜有效饲养量及饲养结构在1978-2020年间的时间分布特征,然后基于变异系数法和标准差椭圆方法测度了牲畜饲养结构空间分布特征,最后利用地理探测器模型分析了牲畜饲养结构空间分异性的核心驱动因素。结果表明:1)宁夏牲畜饲养结构在2002年前后发生了明显变化,牛、羊饲养比例明显上升,猪的饲养比例下降。2)牛、羊、猪饲养比例都呈空间分异性,但空间异质性的变化趋势各不相同。3)牛、羊、猪饲养比例均呈由南-北向分布向东北-西南向分布转变的趋势,牛、羊饲养比例较高区域均呈向四周扩张的趋势。4)牛饲养比例的核心驱动因素包括自然资源条件、社会经济条件以及政策因素,羊饲养比例的核心驱动因素包括社会经济条件和政策因素,而猪饲养比例只受到社会经济条件的影响。大部分核心驱动因素间的交互作用会增强牲畜饲养比例的空间分异性。

关键词：有效饲养量牲畜饲养结构空间分异性地理探测器驱动因素

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What are the keys to influence the life satisfaction of eco-migrants in the northern foot of the Qilian Mountains?A test based on the livelihood risk interaction

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Journal of Mountain Science 2022年第11期19卷 3227-3245页

作者： WANG Ya zhou li-hua Key Laboratory of Desert and Desertification Northwest Institute of Eco-environment and ResourcesChinese Academy of SciencesLanzhou 730000China Institutes of Science and Development Chinese Academy of SciencesBeijing 100190China School of public policy and management University of Chinese Academy of SciencesBeijing 100049China

Eco-migrants'ability to adapt to livelihood risks and their satisfaction with lives directly affect the ecological and economic benefits of ecological migration *** formulate an effective livelihood risk prevention system and welfare guarantee mechanism,we took the ecomigrants in Wuwei City as an example,developed an integrated analytical framework for life satisfaction and employed linear regression models to identify the interactions between livelihood risk and life *** findings indicate that 94.66%of eco-migrants in Wuwei City are threatened by livelihood risks after *** living expenses,poor quality of redistributed production goods,and re-poverty constitute the main *** risk multiplicity index is *** cultural types,there are no significant differences in regions and livelihoods.A total of 55.73%of eco-migrants are satisfied with their lives,with the liangzhou district scoring the *** for satisfaction with development potential and public services,no significant intergroup differences were found among regions and livelihood ***-migrant's life satisfaction is significantly affected by livelihood ***-migrants'satisfaction with living income,social integration,farmer-friendly policies and overall life is negatively affected by the risk of repoverty and inadequate social *** ecomigrant's satisfaction with development potential and community construction is not influenced by one type of risk alone,but the interaction between risks has a strong *** interaction of welfare risks with economic risks and policy risks will balance and weaken the adverse effects of a single risk on those elements in the economic and policy *** study offers novel ideas for rural revitalization,hollow governance,and well-being assurance.

关键词： Eco-migrant livelihood risk life satisfaction Northern foot of Qilian Mountain

基于竞争态模型的甘肃省草食畜牧业发展格局演化与提升路径研究

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草业学报 2024年第2期33卷 39-56页

作者：石贵王娅杨国靖李军豪周立华裴孝东中国科学院西北生态环境资源研究院甘肃兰州730000 中国科学院大学北京100049 干旱区生态安全与可持续发展重点实验室甘肃兰州730000 中国科学院科技战略咨询研究院北京100190

草食畜牧业的高质量可持续发展是中国乡村振兴战略中重要的一环,准确把握各区域畜牧发展格局,保障区域内草食畜牧业的良性发展,促进乡村产业振兴显得愈发重要。本研究基于《中国农村统计年鉴》《甘肃农村年鉴》《甘肃发展年鉴》中牛和... 详细信息

草食畜牧业的高质量可持续发展是中国乡村振兴战略中重要的一环,准确把握各区域畜牧发展格局,保障区域内草食畜牧业的良性发展,促进乡村产业振兴显得愈发重要。本研究基于《中国农村统计年鉴》《甘肃农村年鉴》《甘肃发展年鉴》中牛和羊养殖数据,利用竞争态模型、重心迁移模型分析了1991-2019年甘肃省在省、市、县3个尺度下牛羊养殖竞争态现状、转移模式与重心迁移模式,并从社会经济、自然资源两个角度分析了其相关因素,并讨论了甘肃省未来畜牧养殖策略。结果表明:1)竞争态的转移具有规律性,维持“瘦狗-幼童”的低质量循环、“明星-金牛”的高质量循环,两个循环间难以实现跨越式发展,甘肃省于2006年后完成了两个循环间的跨越,并保持高质量循环至今;2)畜牧养殖的竞争态转移模式、重心迁移模式与自然资源、社会经济条件表现出较高的契合度,可以作为养殖策略选择的重要指标;3)甘肃省下一步应采取扩张战略,扩张省内呈明星态的养殖地、稳固金牛型养殖地,对瘦狗型养殖地与幼童型养殖地可能需考虑紧缩战略。本研究旨在为区域草食畜牧业的合理发展与战略规划提供科学依据和参考。

关键词：竞争态模型草食畜牧业重心转移战略选择甘肃省

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注洗油线腐蚀开裂原因分析及修复工装的应用

全面腐蚀控制 2024年第8期38卷 163-165页

作者：杜亮马腾飞石玲周利华刘元涛新疆炼化建设集团有限公司

随着化工装置的长周期运行，设备和管道都存在壁厚减薄、腐蚀穿孔、应力开裂等泄漏问题。我单位根据多年带压堵漏经验，对易燃易爆管道封堵包焊过程制作专用工装，并全过程进行充氮气保护焊接，成功在某部压缩10-K-201压缩机正常运转的... 详细信息

随着化工装置的长周期运行，设备和管道都存在壁厚减薄、腐蚀穿孔、应力开裂等泄漏问题。我单位根据多年带压堵漏经验，对易燃易爆管道封堵包焊过程制作专用工装，并全过程进行充氮气保护焊接，成功在某部压缩10-K-201压缩机正常运转的情况下，通过使用本技术成功将泄漏隐患消除。本文重点分析了裂纹产生的原因，阐述了在可燃气体泄漏情况下充氮保护工装的研发与应用，该技术可有效保障了人员安全与次生事故的发生，避免装置的紧急停工。

关键词：裂纹泄露焊接

一种超声多普勒诊断仪质量控制体模研制及应用

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中国医疗器械信息 2024年第14期30卷 7-9,28页

作者：吴小婷汪哲民周丽华深圳市龙岗中心医院医学装备管理部广东深圳518112

目的:研制一种超声多普勒诊断仪质量控制体模,用于医疗设备应用质量技术评估。现医疗机构中超声多普勒诊断仪质量控制规范尚未健全,监管不到位,不少设备“带病”作业,不良事件时有发生,加强质量控制刻不容缓。本文将根据现有超声多普勒... 详细信息

目的:研制一种超声多普勒诊断仪质量控制体模,用于医疗设备应用质量技术评估。现医疗机构中超声多普勒诊断仪质量控制规范尚未健全,监管不到位,不少设备“带病”作业,不良事件时有发生,加强质量控制刻不容缓。本文将根据现有超声多普勒诊断仪的质量控制手段,更进一步研究,对超声多普勒诊断仪质量控制体模研制及应用。方法:根据超声多普勒成像原理研究及分析现有模体的优劣,按中国国标选定模体检测功能项目,依据常规标准成人血管大小设计仿制血管外径和内径进行模拟血管,制作琼脂凝胶型体模,琼脂凝胶体模内部穿了两根硅胶管,用蠕动泵驱动,可以控制流速和方向,模拟血流速度变化、血流状态、模拟血流方向识别,还有探测深度,在超声下验证各项指标。结果:研制了超声多普勒诊断仪质量控制体模,通过模拟人体组织和血流,通过可控流速和方向以及深度,通过超声多普勒诊断仪探头进行探测,以便验证该设备和探头的性能可靠性、快速、精准检测,达到研制目的。结论:随着超声多普勒诊断仪的发展,超声成像技术也在不断提升,而超声成像作为医学诊断中的数据显得尤为重要。在超声多普勒诊断仪使用场所的变化下,性能指标质量下降所带来的问题也逐渐暴露,本文结合医院彩超在使用过程中质量控制体模研制,对超声多普勒诊断图像质量进行探讨分析,以便更好地掌握超声多普勒诊断仪的质量控制方法,确保图像质量。

关键词：超声多普勒诊断仪体模质量控制仿组织

Multiscale causes of the 2022 Yangtze mega-flash drought under climate change

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Science China Earth Sciences 2024年第8期67卷 2649-2660页

作者： Xing YUAN Yumiao WANG Shiyu zhou hua li Chenyuan li School of Hydrology and Water Resources Nanjing University of Information Science and TechnologyNanjing 210044China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China Key Laboratory of Hydrometeorological Disaster Mechanism and Warning of Ministry of Water Resources Nanjing University of Information Science and TechnologyNanjing 210044China

The 2022 Yangtze mega-flash drought is characterized by strong intensity and rapid development both in time and space,accompanied by a persistent anticyclonic circulation ***,the causes of the extreme event remain elusive given the multiscale nature of *** we presented a brief overview for the oceanic and terrestrial causes of the megaflash drought during the summer of 2022,and estimated the risk in a changing *** the soil moisture percentile as the drought index,it was found that the drought expanded to the entire Yangtze River basin within two months,with 80%of basin under severe drought conditions at the end of *** the intensity and onset speed of the 2022 mega-flash drought were ranked as the first during the past 62 years,with return periods of 86 and 259 years,*** results of composite analysis showed that the spring La Ni?a can facilitate the abrupt change from a wet/normal condition in May–June to drought in July–August over the Yangtze River basin,which was beneficial for the increase of flash drought intensity and onset speed *** analysis through the linear regression also indicated that the unprecedented intensity was associated with the negative phase of the Pacific Decadal *** by a coupling strength index for soil moisture and vapor pressure deficit,it was found that there was a strong land-atmosphere coupling over the Yangtze River basin during July–August *** attribution by using CMIP6 climate models suggested that land-atmosphere coupling increased the risks of flash drought intensity and onset speed like 2022 by 61%±6%and 64%±7%under natural climate forcings,and the synergy of coupling and anthropogenic climate change would increase the risks by 75%±22%and 85%±12%.Our findings emphasized the role of landatmosphere coupling combined with anthropogenic climate change in intensifying flash droughts.

关键词： Flash drought Yangtze River basin Land-atmosphere coupling Climate change Attribution

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Mechanism of local solidification time variations with melt rate during vacuum arc remelting process of 8Cr4Mo4V high-strength steel

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Journal of Iron and Steel Research(International) 2024年第2期31卷 377-388页

作者： Tao Pan Hong-chun Zhu zhou-hua Jiang hua-bing li Rui Zhang Hao Feng School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina

A 2D axisymmetric numerical model was established to investigate the variations of molten pool with different melt rates during the vacuum arc remelting of 8Cr4Mo4V high-strength steel,and the ingot growth was simulated by dynamic mesh *** results show that as the ingot grows,the molten pool profile changes from shallow and flat to V-shaped,and both the molten pool depth and the mushy width ***,the variation of both the molten pool shape and the mushy width melt rate is clarified by the thermal equilibrium *** melt rate increases,both the molten pool depth and the mushy width *** is caused by the increment in sensible heat stored in the ingot due to the limitation of the cooling capacity of the *** nonlinear increment in sensible heat leads to a nonlinear increase in the mushy *** addition,as melt rate increases,the local solidification time(LST)of ingot decreases obviously at first and then *** melt rate is controlled in a suitable range,LST is the lowest and the secondary dendrite arm spacing of the ingot is the smallest,which can effectively improve the compactness degree of 8Cr4Mo4V high-strength steel.

关键词： 8Cr4Mo4V high-strength steel Vacuum arc remelting process Melt rate Molten pool Local solidification time

Precise genome-editing in human diseases:mechanisms,strategies and applications

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Signal Transduction and Targeted Therapy 2024年第3期9卷 1065-1085页

作者： Yanjiang Zheng Yifei li Kaiyu zhou Tiange li Nathan J.VanDusen Yimin hua Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE Department of PediatricsWest China Second University HospitalSichuan UniversityChengduSichuan 610041China Department of Cardiovascular Surgery West China HospitalSichuan UniversityChengduSichuan 610041China Department of Pediatrics Herman B Wells Center for Pediatric ResearchIndiana University School of MedicineIndianapolisIN 46202USA

Precise genome-editing platforms are versatile tools for generating specific,site-directed DNA insertions,deletions,and *** continuous enhancement of these tools has led to a revolution in the life sciences,which promises to deliver novel therapies for genetic *** genome-editing can be traced back to the 1950s with the discovery of DNA’s doublehelix and,after 70 years of development,has evolved from crude in vitro applications to a wide range of sophisticated capabilities,including in vivo ***,precise genome-editing faces constraints such as modest efficiency,delivery challenges,and off-target *** this review,we explore precise genome-editing,with a focus on introduction of the landmark events in its history,various platforms,delivery systems,and ***,we discuss the landmark events in the history of precise ***,we describe the current state of precise genome-editing strategies and explain how these techniques offer unprecedented precision and versatility for modifying the human ***,we introduce the current delivery systems used to deploy precise genome-editing components through DNA,RNA,and ***,we summarize the current applications of precise genome-editing in labeling endogenous genes,screening genetic variants,molecular recording,generating disease models,and gene therapy,including ex vivo therapy and in vivo therapy,and discuss potential future advances.

关键词： precise generating editing