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行业工资变动对我国高等教育结构的影响——基于工资比较的计量分析

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高校教育管理 2020年第1期14卷 89-97页

作者：李玉栋陕西师范大学教育学院

在市场经济条件下,工资收入通过影响学生及其家庭对高等教育的不同需求从而拉动高等教育结构调整。本研究通过构建一阶自回归分布滞后模型进行分析,发现行业工资变动整体上对我国高等教育的层次结构和学科结构调整有显著的影响作用,且... 详细信息

在市场经济条件下,工资收入通过影响学生及其家庭对高等教育的不同需求从而拉动高等教育结构调整。本研究通过构建一阶自回归分布滞后模型进行分析,发现行业工资变动整体上对我国高等教育的层次结构和学科结构调整有显著的影响作用,且不同行业的比较优势变化对高等教育层次结构和学科结构变动的影响具有差异性。面对发展的新环境和新挑战,优化高等教育结构,我国应该进一步树立正确的价值导向,构建高等教育结构调整的多元主体协同和现代化治理路径,并依靠信息化的科学决策体系,形成动态调整机制。

关键词：高等教育层次结构学科结构行业工资工资比较

Copper-Catalyzed Synthesis of 2-Arylquinazolinones from 2-Arylindoles with Amines or Ammoniums

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Copper-Catalyzed Synthesis of 2-Arylquinazolinones from 2-Ar...

Preliminary Investigation of Impurity and Radiation Behaviors in the Startup Phase of HL-2A Tokamak

中国化学会第九届全国有机化学学术会议

作者： Yadong Feng yudong li Guolin Cheng lianhui Wang Xiuling Cui School of Biomedical Science Huaqiao University

＜正＞Quinazolinone is a ubiquitous and significant heterocycle and widely exists in natural alkaloids and pharmaceuticals[1].As a result,numerous methods for synthesis of quinazolinone derivatives have been developed[2].Herein,we present a copper-catalyzed expansion reaction of 2-arylindoles with amines or ammoniums,affording both 2-substituted and 2,3-disubstituted quinazolinones,

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Southwestern Institute of Physics Annual Report

Southwestern Institute of Physics Annual Report 2004年第1期 20-21页

作者： li Wei PAN yudong CUI Zhengying LUO Junlin DONG Jiafu

As the startup phase of HL-2A operation and the first divertor tokamak device in China, it is important to identify the species of impurity, estimate the concentration of impurities and compare the different behaviors of radiation in limiter and divertor configurationt. In startup phase of HL-2A, glowing discharge cleaning （GDC） is used as a conventional wall conditioning technology and titanium gettering is used occasionally in closed divertor chamber during SN configuration discharges phase.

关键词： Impurity Radiation Wall conditioning

Vegetation and Soil Characteristics of Different Desertification Grasslands in Northwest Sichuan

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Animal Husbandry and Feed Science 2014年第2期6卷 66-71,74页

作者： Wan Ting Tu Weiguo Xi Huan li yudong Tang Xuefang Yang Yichuan Sichuan Province Natural Resources Science Academy

[Objective]The paper was to study vegetation and soil characteristics of different desertification grasslands in northwest Sichuan. [Method]By taking different desertification grasslands as the research object,the characteristic factors of vegetation community,biomass,soil moisture content,volume weight and porosity were analyzed through scientific investigation,sampling and formula calculation to reveal the changes in vegetation and soil characteristics of different desertification grasslands in Northwest Sichuan. [Result]Community succession presented the pattern of " hygrophyte-mesophyte-xerophyte" with the aggravation of grassland desertification. The height and coverage of community decreased,species richness was declined by 88%,and composition of dominant species also changed greatly. The diversity index of light-desertification grassland was the highest among tested grasslands. Total biomass was decreased by 90. 4%,and the underground biomass decreased far more than aboveground biomass. In desertification progress,both soil moisture content and water holding capacity decreased,while volume weight showed upward trend and porosity showed downward trend; soil characteristics had large variation in early stage of desertification,so restoration treatment of desertification grassland should be carried out in the early stage of desertification. [Conclusion]The study provided a theoretical basis for researches on causes and management programs of desertification grassland,having an important meaning for ecological restoration of regional grassland and maintenance of ecological security.

关键词： Grassland Desertification Vegetation Biomass Soil

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生态足迹分析与西北城市建设研究

干旱区资源与环境 2009年第5期23卷 15-18页

作者：李育冬新疆大学经济与管理学院乌鲁木齐830046

生态承载力理论是生态学研究的核心内容之一,是可持续发展研究的主要支撑理论。对于实现区域可持续发展也具有重要的现实意义,因而成为可持续发展研究的前沿和热点。生态足迹是近年来渐为流行的一种定量测算人类对自然利用程度的新方法... 详细信息

生态承载力理论是生态学研究的核心内容之一,是可持续发展研究的主要支撑理论。对于实现区域可持续发展也具有重要的现实意义,因而成为可持续发展研究的前沿和热点。生态足迹是近年来渐为流行的一种定量测算人类对自然利用程度的新方法,该方法能定量判断一个区域的发展是否处于生态承载力的范围内,从而能定量反映人类活动对自然生态环境产生的压力和影响程度,为区域生态系统研究提供新的思路和方向。以库尔勒市为研究对象,通过对该市2005年生态足迹的计算,分析了在此期间生态足迹的动态变化过程。生态赤字逐年上升说明库尔勒市总体经济发展模式还有待进一步改进。由集散型向节约型转变,注重提高资源利用效率,提倡节约型的生产和生活消费模式,减少生态足迹,逐步迈向生态城市,实现城市的可持续发展是库尔勒市今后社会经济发展的目标模式。

关键词：生态足迹生态承载力库尔勒市

功能梯度碳纳米管增强复合材料板弯曲和模态的广义有限差分法

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力学学报 2022年第2期54卷 414-424页

作者：李煜冬傅卓佳汤卓超河海大学力学与材料学院南京211100

由复合材料构成的板结构一直以来受到很大关注,其中功能梯度碳纳米管增强复合材料(functionally graded carbon nanotube-reinforced composite, FG-CNTRC)具有异常优越的力学性能,使得诸多学者展开了对功能梯度碳纳米管增强复合材料板... 详细信息

由复合材料构成的板结构一直以来受到很大关注,其中功能梯度碳纳米管增强复合材料(functionally graded carbon nanotube-reinforced composite, FG-CNTRC)具有异常优越的力学性能,使得诸多学者展开了对功能梯度碳纳米管增强复合材料板结构力学行为的研究.本文以FG-CNTRC板为研究对象,将一种新型的区域型无网格方法——广义有限差分法应用于求解基于一阶剪切变形的FG-CNTRC板结构的静态线性弯曲和自振模态问题.广义有限差分法(generalized finite difference method, GFDM)基于函数的泰勒展开式和移动最小二乘法将计算区域中任意一子区域中心点处函数值的各阶偏导数表示成该支撑域节点上函数值的线性叠加.该方法不仅无需网格划分和数值积分而且避免了全域无网格配点法通常遇到的病态稠密矩阵问题,使得这类方法具有形式简单、易于应用和实现等优点,目前广泛应用于各种科学和工程计算问题.本文首先介绍了基于一阶剪切变形理论的功能梯度碳纳米管增强复合材料板的广义有限差分法离散模型.随后通过基准算例,检验了广义有限差分法的计算精度与收敛性.最后数值分析和讨论了碳纳米管中不同分布型、体积分数、碳纳米管旋转角度、宽厚比、板倾斜角度和长宽比等对FG-CNTRC板结构弯曲和模态的影响.

关键词：广义有限差分法功能梯度碳纳米管增强复合材料一阶剪切变形板弯曲分析模态分析

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西安地铁文物保护实践与思考

城市轨道交通研究 2014年第10期17卷 10-13页

作者：李宇东西安市地下铁道有限责任公司西安高级工程师710018

文物保护是西安地铁建设面临的重点问题。结合西安地铁2号线勘察、研究、设计与施工工作,以分析文物环境变化为基础,探讨了西安地铁建设中文物保护的做法。主要措施为:线路设计应远离变形敏感区且加大埋深,隧道采用盾构法施工,钟楼及城... 详细信息

文物保护是西安地铁建设面临的重点问题。结合西安地铁2号线勘察、研究、设计与施工工作,以分析文物环境变化为基础,探讨了西安地铁建设中文物保护的做法。主要措施为:线路设计应远离变形敏感区且加大埋深,隧道采用盾构法施工,钟楼及城墙预先设置隔离桩并预留注浆加固条件,城墙外皮及拱洞保护,采用无缝钢轨和钢弹簧浮置板减振道床等。经检测,建设阶段文物沉降量符合设计要求,试运营阶段振动指标满足文物局和相关规范要求。文物保护措施应偏向安全,实施中留有余地,加强文物维修的动态管理。

关键词：西安地铁文物保护工程措施

我国西部旅游业可持续发展的必由之路——生态旅游

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生产力研究 2006年第3期 142-144页

作者：李育冬新疆大学经济与管理学院新疆乌鲁木齐830046

在我国西部地区,生态的脆弱性和资源的日益匮乏,使我们的环保意识有了一定的提高。现实的严峻性和紧迫性使我们逐渐认识到旅游业并非“无烟工业”,使旅游业健康持续发展的必由之路——生态旅游。

关键词：生态旅游可持续发展西部地区旅游业

Deep learning methods for noisy sperm image classification from convolutional neural network to visual transformer:a comprehensive comparative study

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Intelligent Medicine 2024年第2期4卷 114-127页

作者： Ao Chen Chen li Md Mamunur Rahaman yudong Yao Haoyuan Chen Hechen Yang Peng Zhao Weiming Hu Wanli liu Shuojia Zou Ning Xu Marcin Grzegorzek Microscopic Image and Medical Image Analysis Group College of Medicine and Biological Information EngineeringNortheastern UniversityShenyangLiaoning 110169China Department of Electrical and Computer Engineering Stevens Institute of TechnologyHobokenNJ 07030USA School of Arts and Design Liaoning Petrochemical UniversityFushunLiaoning 113001China Institute of Medical Informatics University of LübeckLüebeckGermany

Background With the gradual increase of infertility in the world,among which male sperm problems are the main factor for infertility,more and more couples are using computer-assisted sperm analysis(CASA)to assist in the analysis and treatment of ***,the rapid development of deep learning(DL)has led to strong results in image classification ***,the classification of sperm images has not been well studied in current deep learning methods,and the sperm images are often affected by noise in practical CASA *** purpose of this article is to investigate the anti-noise robustness of deep learning classification methods applied on sperm *** The SVIA dataset is a publicly available large-scale sperm dataset containing three *** this work,we used subset-C,which provides more than 125,000 independent images of sperms and impurities,including 121,401 sperm images and 4,479 impurity *** investigate the anti-noise robustness of deep learning classification methods applied on sperm images,we conducted a comprehensive comparative study of sperm images using many convolutional neural network(CNN)and visual transformer(VT)deep learning methods to find the deep learning model with the most stable anti-noise *** This study proved that VT had strong robustness for the classification of tiny object(sperm and impurity)image datasets under some types of conventional noise and some adversarial *** particular,under the influence of Poisson noise,accuracy changed from 91.45%to 91.08%,impurity precison changed from 92.7%to 91.3%,impurity recall changed from 88.8%to 89.5%,and impurity F1-score changed 90.7%to 90.4%.Meanwhile,sperm precision changed from 90.9%to 90.5%,sperm recall changed from 92.5%to 93.8%,and sperm F1-score changed from 92.1%to 90.4%.Conclusion Sperm image classification may be strongly affected by noise in current deep learning methods;the robustness with regard to noise of VT methods based

关键词： Computer-assisted sperm analysis Anti-noise Robustness Deep learning .Image classification Sperm image Conventional noise Adversarial attacks Convolutional neural network Visual transformer