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数字技术对制造业全球价值链分工地位升级影响研究

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重庆理工大学学报（社会科学） 2024年第5期38卷 25-39页

作者：周升起衣彩娇青岛大学经济学院山东青岛266071 青岛大学山东省世界经济研究基地山东青岛266071

随着数字技术进步及其在经济各领域的快速应用,其对产业全球价值链(GVC)地位升级的推动作用日益显著。基于OECD-TiVA联合发布TiVA数据库2006—2018年的数据,以64个经济体为研究样本,实证检验数字技术对制造业GVC分工地位升级的影响。研... 详细信息

随着数字技术进步及其在经济各领域的快速应用,其对产业全球价值链(GVC)地位升级的推动作用日益显著。基于OECD-TiVA联合发布TiVA数据库2006—2018年的数据,以64个经济体为研究样本,实证检验数字技术对制造业GVC分工地位升级的影响。研究结果显示:数字技术显著促进制造业GVC分工地位的升级;提高劳动生产率、优化人力资本结构以及刺激消费需求,是数字技术促进制造业GVC分工地位升级的作用机制。异质性分析表明:数字技术对于低互联网发展水平以及中低收入经济体GVC分工地位升级的促进作用更为明显。据此提出,增强数字技术对我国制造业GVC分工地位升级的促进作用,应大幅提升我国数字技术创新和应用能力;增强贸易规则话语权,推动“数字贸易”发展;加快培养数字技术人才,加速推动消费结构升级。

关键词：数字技术制造业全球价值链地位人力资本消费需求

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一种顾及参数稀疏的GNSS瞬时钟差模型

大地测量与地球动力学 2024年第3期44卷 263-266,320页

作者：周圣淇王中元胡超王瑞光姚雪燕中国矿业大学环境与测绘学院江苏省221116 安徽理工大学空间信息与测绘工程学院安徽省232001

提出一种顾及参数稀疏的GNSS瞬时钟差模型构建算法,该算法通过在最小二乘多项式拟合中附加L 1范数项(Lasso)进行约束,并采用滑动建模的方式拟合钟差模型,即滑动Lasso拟合法。使用GFZ 300 s钟差产品作为训练数据,通过10折交叉验证获得正... 详细信息

提出一种顾及参数稀疏的GNSS瞬时钟差模型构建算法,该算法通过在最小二乘多项式拟合中附加L 1范数项(Lasso)进行约束,并采用滑动建模的方式拟合钟差模型,即滑动Lasso拟合法。使用GFZ 300 s钟差产品作为训练数据,通过10折交叉验证获得正则化参数,建立钟差模型,并与常用的钟差建模加密算法进行卫星钟差拟合精度与PPP定位精度对比。实验结果表明,滑动Lasso拟合法在进行钟差拟合建模时,对于局部钟差数据中出现跳变过大的钟差值,可以有效消除其在拟合过程中对模型造成的影响,防止模型过拟合,进而提高钟差模型的拟合精度与PPP定位精度。

关键词： Lasso 交叉验证稀疏模型钟差建模滑动式

Laboratory simulation of the influence of geothermal heating on the interior ocean

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Acta Oceanologica Sinica 2014年第9期33卷 25-31页

作者： zhou shengqi QU Ling ZHAO Xiaozheng WAN Wei State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Sciences University of Chinese Academy of Sciences

This study, using laboratory experiments and scaling analysis, evaluates the influence of geothermal heating on global oceanic circulation. Upon a well-developed large-scale convective flow, an additional heat flux perturbation 5F/F is employed. The increments of flow and thermal properties, including eddy diffusivity K7, flow velocity Vand bottom temperature Tb, are found to be independent of the applied heat flux F. Together with the scaling analysis of convective flow at different configurations, where the flow is thermally driven in the relatively low or extremely high turbulent thermal convections or the horizontal convection, the variances of flow properties, 6KT/KTand 6V/V, are found to be close to 0.5% and 0.75% at 5F/F=2%. This means that the small heat flux perturbation plays a negligible role in the global convective flow. However, 6Tb/ATis found to be 1.5% at 8F/F=2%, which would have a significant effect in the local region. The results might provide a clue to understanding the influence of geothermal heating on global oceanic circulation. It is expected that geothermal heating will contribute less than 1% in turbulent mixing and volume flux to global oceanic circulation, so its influence can be negligible in this situation. However, when it comes to the local environment, the influence of geothermal heating cannot be ignored. For example, temperature increases of about 0.5℃ with geothermal heating would have a significant effect on the physical environments within the benthic boundary layer.

关键词： geothermal heating oceanic circulation turbulent mixing temperature velocity

Statistical characteristics of the surface ducts over the South China Sea from GPS radiosonde data

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Acta Oceanologica Sinica 2015年第11期34卷 63-70页

作者： CHENG Yinhe zhou shengqi WANG Dongxiao LU Yuanzheng YAO Jinglong Guangdong Province Key Laboratory of Coastal Ocean Variation and Disaster Prediction College of Ocean and Meteorology Guangdong Ocean University State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Sciences

Based on the global position system （GPS） radiosonde data near the sea surface, the surface duct characteristics over the South China Sea （SCS） were statistically analyzed. The annual surface duct occurrence over the SCS was about 64%. Of the observed surface ducts, duct heights mainly distributed between 18 and 42 m, with M slopes in the range of -0.3 to -0.2 M units/m. Those ducts accounted for about 80% of the ducting cases. For the total profiles, the duct occurrences in a day changed slowly and were more than 60% in all times. The surface ducts formed more easily in the daytime than in the nighttime and most of the duct height were at bellow about 32 m. Additionally, The seasonal variation of the SCS ducts appeared to be evident, except that the mean duct thickness was almost constant, about 33 m for all seasons. The highest occurrence was about 71% in the autumn, followed by in the summer, spring and winter. In spring, their top-height existed more often at a height of more than 48 m. Their mean duct strength became stronger trend from spring to winter, with the M-slope in the range between -0.26 and -0.18 M units/m. Those results agreed well with other studies, provided considering the data resolution. The statistical analysis was reliable and gave the duct estimation for the SCS. Such duct climatology not only has important implications for communication systems and the reliability of the radar observation, but also can provide useful information to improve the accuracy of the meteorological radar measurements.

关键词： GPS radiosonde surface ducts distribution daily variation seasonal variation

CO_(2)/O_(2)在不同含水率烟煤中的竞争吸附模拟研究

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华北科技学院学报 2024年第3期21卷 10-15页

作者：周生啟张雅宙汤晓辰程根银蔡春城上海大屯能源股份有限公司江苏分公司孔庄煤矿江苏徐州221600 华北科技学院安全工程学院北京东燕郊065201

为研究CO_(2)/O_(2)混合气体在不同含水率烟煤中的竞争吸附特征,分别建立了含水率为1.42%、3.48%和5.45%的烟煤分子模型,在不同温度和压力条件下进行煤对CO_(2)/O_(2)混合气体的吸附模拟研究。结果表明:不同含水率煤中CO_(2)的吸附能力... 详细信息

为研究CO_(2)/O_(2)混合气体在不同含水率烟煤中的竞争吸附特征,分别建立了含水率为1.42%、3.48%和5.45%的烟煤分子模型,在不同温度和压力条件下进行煤对CO_(2)/O_(2)混合气体的吸附模拟研究。结果表明:不同含水率煤中CO_(2)的吸附能力优于O_(2),煤中水分含量增加对CO_(2)和O_(2)气体的吸附起到抑制作用,并且对CO_(2)的抑制作用更强。整个体系的相互作用能与CO_(2)的比例成正比,与煤的含水率成反比。说明向煤层注入CO_(2)时,含水率越高越不利于煤对气体的吸附,低压低温状态有利于增强防治煤自燃的效果。

关键词： CO_(2)/O_(2)混合气体竞争吸附含水率相互作用能

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基于模态分析的宽频带振荡区域定位研究

山东电力技术 2024年第2期51卷 37-45页

作者：周生奇菅学辉钟世民孙鹏菊李强国网山东省电力公司青岛供电公司山东青岛266002 重庆大学重庆400044

伴随化石能源的枯竭和我国能源转型战略的推进,新能源发电系统上网电量不断增加。电力系统“双高”特性日益显著,系统运行面临更为复杂的挑战,其中电力电子装置引发的宽频带振荡备受关注。因此,针对新能源系统宽频带振荡产生的机理,提... 详细信息

伴随化石能源的枯竭和我国能源转型战略的推进,新能源发电系统上网电量不断增加。电力系统“双高”特性日益显著,系统运行面临更为复杂的挑战,其中电力电子装置引发的宽频带振荡备受关注。因此,针对新能源系统宽频带振荡产生的机理,提出一种基于模态分析的宽频带振荡区域定位方法,用于新能源系统振荡频率和振荡区域定位。根据逆变器、线路阻抗和电网阻抗等系统参数,建立不同型号逆变器并联系统的高阶导纳矩阵。对矩阵进行等效变换,通过绘制模态阻抗随频率变化的曲线,得到系统可能的谐振频率。通过节点参与因子计算,定位振荡的区域。通过仿真验证,模态分析方法可以实现宽频谐振的精准频率定位和区域定位,可为新能源场站接入评估和事故定位提供依据。

关键词：模态分析宽频带振荡振荡定位

Laboratory simulation of the influence of geothermal heating on the global oceanic circulation

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Laboratory simulation of the influence of geothermal heating...

Origin of the temperature oscillation in turbulent thermal convection

23rd International Congress of Theoretical and Applied Mechanics

作者： shengqi zhou Xiaozheng Zhao State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of Sciences

＜正＞In this study,the influence of geothermal heating on the global oceanic circulation is evaluated with laboratory experiments and scaling *** a well-developed large scale convective flow（LSC）,an additional heat...

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Origin of the temperature oscillation in turbulent thermal c...

中国力学大会——2013

作者： Xi Hengdong zhou shengqi zhou Quan Xia Keqing Shenzhen Graduate School Harbin Institute of Technology South China Sea Institute of Oceanology Shanghai Institute of Applied Mathematics and Mechanics Physics Department The Chinese University of Hong Kong

We report an experimental study of the three-dimensional spatial structure ofthe low-frequency temperature oscillations in a cylindrical Rayleigh-Benard convection *** simultaneous multipoint temperature measurements it is found that, contrary to the popular scenario,thermal plumes are emitted neither periodically nor alternately,but randomly and continuously, from the top and bottom *** further identify a

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仿生变刚度关节设计与试验

农业机械学报 2018年第1期49卷 390-396页

作者：王颜房立金周生啟东北大学机械工程与自动化学院沈阳110819 东北大学机器人科学与工程学院沈阳110819

变刚度关节是一种具有本质柔顺性的机器人机构,能够提高机器人与人交互作用时的安全性。本文设计了一种采用弹簧片的机械式仿生变刚度关节,利用差动轮系实现关节位置与刚度的独立控制。基于弹簧片大挠度变形,在关节中采用的2种弹簧片末... 详细信息

变刚度关节是一种具有本质柔顺性的机器人机构,能够提高机器人与人交互作用时的安全性。本文设计了一种采用弹簧片的机械式仿生变刚度关节,利用差动轮系实现关节位置与刚度的独立控制。基于弹簧片大挠度变形,在关节中采用的2种弹簧片末端施力结构对刚度特性的影响进行分析,仿真结果表明,末端施力结构对偏转时的刚度变化有较大影响。对变刚度关节样机的刚度性能进行试验,试验结果与仿真结果一致,表明该关节具有较大的刚度变化范围,并且2种末端施力结构可以分别满足持续高刚度和碰撞安全性的应用要求。

关键词：变刚度机器人关节弹簧片