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经济增长压力对生态保护与高质量发展耦合协调的影响——基于黄河流域地级市的实证分析

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工业技术经济 2024年第7期43卷 61-69页

作者：边志强张倩华山西财经大学资源型经济转型发展研究院太原030006

本文基于2006~2022年黄河流域九省区99个地级市的面板数据,考察了经济增长压力对生态保护与高质量发展耦合协调的影响效应、内在机制及异质性表现。结果表明:(1)2006~2022年,黄河流域生态保护与高质量发展耦合协调水平呈现波动上升趋势... 详细信息

本文基于2006~2022年黄河流域九省区99个地级市的面板数据,考察了经济增长压力对生态保护与高质量发展耦合协调的影响效应、内在机制及异质性表现。结果表明:(1)2006~2022年,黄河流域生态保护与高质量发展耦合协调水平呈现波动上升趋势,总体从轻度失调发展到一般协调;(2)黄河流域经济增长压力对生态保护与高质量发展耦合协调具有显著而稳健的“倒U型”影响;(3)技术创新和产业结构升级是上述“倒U型”影响得以发挥的两条内在机制;(4)黄河流域经济增长压力对生态保护与高质量发展耦合协调的“倒U型”影响仅显著存在于资源型城市和中上游城市。研究结论可为黄河流域持续有效推进生态保护与高质量发展耦合协调提供经济增长目标设定维度的政策启示。

关键词：黄河流域经济增长压力生态保护高质量发展耦合协调倒U型技术创新产业结构升级

基于拟牛顿法的深度强化学习在车联网边缘计算中的研究

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通信学报 2024年第5期45卷 90-100页

作者：章坚武芦泽韬章谦骅詹明杭州电子科技大学通信工程学院浙江杭州310018 之江实验室天基计算研究中心浙江杭州311121 浙江大学信息与电子工程学院浙江杭州310027 台州学院电子与信息工程学院浙江台州318000

为了解决车联网中由于多任务和资源限制导致的任务卸载决策不理想的问题,提出了拟牛顿法的深度强化学习双阶段在线卸载(QNRLO)算法。该算法首先引入批归一化技术优化深度神经网络的训练过程,随后采用拟牛顿法进行优化,有效逼近最优解。... 详细信息

为了解决车联网中由于多任务和资源限制导致的任务卸载决策不理想的问题,提出了拟牛顿法的深度强化学习双阶段在线卸载(QNRLO)算法。该算法首先引入批归一化技术优化深度神经网络的训练过程,随后采用拟牛顿法进行优化,有效逼近最优解。通过此双阶段优化,算法显著提升了在多任务和动态无线信道条件下的性能,提高了计算效率。通过引入拉格朗日算子和重构的对偶函数,将非凸优化问题转化为对偶函数的凸优化问题,确保算法的全局最优性。此外,算法考虑了车联网模型中的系统传输时间分配,增强了模型的实用性。与现有算法相比,所提算法显著提高了任务卸载的收敛性和稳定性,并能有效处理车联网中的任务卸载问题,具有较高的实用性和可靠性。

关键词：车联网任务卸载深度强化学习拟牛顿法

Influence of geological factors on coal permeability in the Sihe coal mine

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International Journal of Coal Science & Technology 2022年第1期9卷 58-70页

作者： Guangui Zou qianhua zhang Suping Peng Jiasheng She Deliang Teng Chaochao Jin Yuyan Che State Key Laboratory of Coal Resources and Safe Mining BeijingChina College of Geoscience and Surveying Engineering China University of Mining&TechnologyBeijingChina

Permeability of coal reservoirs influence the extraction of coal gas from coal *** coal samples were collected at an anticline and a syncline of the No.3 coal seam in the Sihe coal ***,permeability,pore size,vitrinite reflectance,and liquid nitrogen adsorption of the samples were *** curvatures at the sample locations,and the distance between the sampling locations and the nearest faults were calculated based on seismic *** influences of the evaluated parameters on permeability were *** factors that influence permeability of the No.3 coal seam were extracted using principal component analysis(PCA).Based on the porosity–permeability model derived from the Archie formula and classic Kozeny–Carman equation,we deduced that the permeability of coal increased with an increase in *** an increase in average vitrinite reflectance,permeability decreases first and then *** results showed that coal permeability was regulated by three key components representing three *** first component included pore size,depth,and pore complexity accounting for 52.59%of the variability indicating that it was the most important in controlling *** second component included specific surface area,structural curvature,and porosity,and the third component comprised of specific surface area,porosity,and average vitrinite ***,pore diameter and complexity had significant effects on coal *** results show that researchers and stakeholders must consider the interactions among multiple factors rather than single factors to understand the influences on permeability to facilitate efficient utilization of coalbed methane resources.

关键词： Coal mine Permeability Geological factors Principal component analysis

Micropillar compression using discrete dislocation dynamics and machine learning

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 39-47页

作者： Jin Tao Dean Wei Junshi Yu qianhua Kan Guozheng Kang Xu zhang School of Mechanics and Aerospace Engineering Southwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China

Discrete dislocation dynamics(DDD)simulations reveal the evolution of dislocation structures and the interaction of *** study investigated the compression behavior of single-crystal copper micropillars using fewshot machine learning with data provided by DDD *** types of features are considered:external features comprising specimen size and loading orientation and internal features involving dislocation source length,Schmid factor,the orientation of the most easily activated dislocations and their distance from the free *** yielding stress and stress-strain curves of single-crystal copper micropillar are predicted well by incorporating both external and internal features of the sample as separate or combined *** is found that the machine learning accuracy predictions for single-crystal micropillar compression can be improved by incorporating easily activated dislocation features with external ***,the effect of easily activated dislocation on yielding is less important compared to the effects of specimen size and Schmid factor which includes information of orientation but becomes more evident in small-sized ***,incorporating internal features,especially the information of most easily activated dislocations,improves predictive capabilities across diverse sample sizes and orientations.

关键词： Discrete dislocation dynamics simulations Machine learning Size effects Orientation effects Microstructural features

Chronic pulmonary bacterial infection facilitates breast cancer lung metastasis by recruiting tumor-promoting MHCII^(hi) neutrophils

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Signal Transduction and Targeted Therapy 2023年第9期8卷 4305-4319页

作者： Teng Ma Yu Tang Taolin Wang Yang Yang Yige zhang Ruihuan Wang Yongxin zhang Yi Li Mingbo Wu Miao Tang Xueli Hu Chaoyu Zou Yuan Ren Huan Liu qianhua zhang Heyue Li Min Wu Jing Li Xikun Zhou Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan University610041 ChengduChina Department of Breast Surgery Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of China610072 ChengduChina State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesResearch Unit of Oral Carcinogenesis and ManagementChinese Academy of Medical SciencesWest China Hospital of StomatologySichuan UniversityChengduChina Drug Discovery Center Wenzhou InstituteUniversity of Chinese Academy of Sciences325001 WenzhouChina

Breast cancer can metastasize to various organs,including the *** immune microenvironment of the organs to be metastasized plays a crucial role in the metastasis of breast *** with pathogens such as viruses and bacteria can alter the immune status of the ***,the effect of chronic inflammation caused by bacteria on the formation of a premetastatic niche within the lung is unclear,and the contribution of specific immune mediators to tumor metastasis also remains largely ***,we used a mouse model revealing that chronic pulmonary bacterial infection augmented breast cancer lung metastasis by recruiting a distinct subtype of tumor-infiltrating MHCII^(hi) neutrophils into the lung,which exhibit cancer-promoting ***,MHCII^(hi) neutrophils enhanced the lung metastasis of breast cancer in a cell-intrinsic ***,we identified CCL2 from lung tissues as an important environmental signal to recruit and maintain MHCII^(hi) *** findings clearly link bacterial-immune crosstalk to breast cancer lung metastasis and define MHCII^(hi) neutrophils as the principal mediator between chronic infection and tumor metastasis.

关键词： metastasis lung breast

Optimizing Combination of Units Commitment Based on Improved Genetic Algorithms

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Wuhan University Journal of Natural Sciences 2007年第6期12卷 1003-1007页

作者： LAI Yifei zhang qianhua JIA Junping School of Economics and Management Wuhan University Wuhan 430072 Hubei China

GAs are general purpose optimization techniques based on principles inspired from the biological evolution using metaphors of mechanisms, such as natural selection, genetic recombination and survival of the fittest. By use of coding betterment, the dynamic changes of the mutation rate and the crossover probability, the dynamic choice of subsistence, the reservation of the optimal fitness value, a modified genetic algorithm for optimizing combination of units in thermal power plants is proposed. And through taking examples, test result are analyzed and compared with results of some different algorithms. Numerical results show available value for the unit commitment problem with examples.

关键词： generating units unit commitment genetic algorithms

母国营商环境优化如何影响企业“走出去”的广度与深度

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投资研究 2023年第9期42卷 72-89页

作者：张倩华刘军山西财经大学资源型经济转型发展研究院山西财经大学国际贸易学院

本文理论分析了营商环境优化影响企业OFDI及其广度与深度的内在机制,之后通过构建城市层面的营商环境指数,并采取2004-2019年深沪A股上市公司数据进行了实证检验。结果表明:营商环境优化促进了企业OFDI,且对OFDI广度的影响大于深度;企... 详细信息

本文理论分析了营商环境优化影响企业OFDI及其广度与深度的内在机制,之后通过构建城市层面的营商环境指数,并采取2004-2019年深沪A股上市公司数据进行了实证检验。结果表明:营商环境优化促进了企业OFDI,且对OFDI广度的影响大于深度;企业生产率提升是上述现象呈现的内在机制。分样本考察发现,营商环境优化对企业OFDI的促进效应及内在机制在国有企业、服务业、内陆地区和发达东道国存在,但在广度和深度的影响上呈现出较强的异质性。

关键词：营商环境 OFDI 投资广度投资深度

A wind tunnel investigation on the transverse motion of aeolian sand

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Research in Cold and Arid Regions 2011年第1期3卷 13-16页

作者： ZhenTing Wang qianhua zhang ZhiBao Dong Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou Gansu 730000 China School of Physical Science and Technology Lanzhou University Lanzhou Gansu 730000 China

A wind tunnel experiment was performed to investigate aeolian grain motions in the transverse direction, which is perpendicular to the incoming flow and parallels the sand bed. The trajectories in the horizontal plane were recorded by high-speed camera. Statistical analysis of 630 trajectories shows that both the motion orientation and the time-averaged speed follow Gaussian distributions. An exclusive method was used to analyze the driving mechanism. It was concluded that the three-dimensional turbulent air flow, rather than the spin of grain or grain-bed collisions, controls the transverse motion.

关键词： aeolian sand transport transverse motion wind tunnel

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改进的双曲正切函数的变步长LMS算法

通信学报 2020年第11期41卷 116-123页

作者：章坚武余皓章谦骅杭州电子科技大学通信工程学院浙江杭州310018 之江实验室智能网络研究中心浙江杭州311121

为了解决定步长LMS算法不能同时满足快速收敛和低稳态误差的问题,提出了一种基于改进双曲正切函数的变步长LMS算法(IVSSLMS)。该算法利用步长反馈因子的二范数和误差信号的相关值来调节步长,克服了定步长算法收敛速度慢及抗噪声能力差... 详细信息

为了解决定步长LMS算法不能同时满足快速收敛和低稳态误差的问题,提出了一种基于改进双曲正切函数的变步长LMS算法(IVSSLMS)。该算法利用步长反馈因子的二范数和误差信号的相关值来调节步长,克服了定步长算法收敛速度慢及抗噪声能力差的问题;并从理论上分析了算法的性能,给出了参数的取值方法。仿真实验结果表明,在高/低信噪比条件下,IVSSLMS算法比已有变步长算法的收敛速度更快、稳态误差更小、系统跟踪能力更优。

关键词：最小均方算法双曲正切函数稳态误差归一化