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贸易政策不确定性能否提升企业社会责任?

国际商务研究 2025年第1期46卷 34-45页

作者：梁俊伟贺铭楷广东外语外贸大学广东广州510003 中电建海上风电工程有限公司海南海口570203

随着中国经济增长,进出口规模持续扩大,中国面临的贸易政策不确定性也达到了前所未有的程度。研究发现,贸易政策不确定性显著抑制了企业的ESG表现,在经过替代被解释变量以及工具变量法等一系列稳健性检验后,该结论依然成立。进一步研究... 详细信息

随着中国经济增长,进出口规模持续扩大,中国面临的贸易政策不确定性也达到了前所未有的程度。研究发现,贸易政策不确定性显著抑制了企业的ESG表现,在经过替代被解释变量以及工具变量法等一系列稳健性检验后,该结论依然成立。进一步研究发现,非国有企业、规模较小企业和所处地区市场化程度高的企业受到的抑制作用更加明显;贸易政策不确定性对非污染企业ESG表现存在抑制作用,但对重污染企业的抑制作用并不显著。贸易政策不确定性会增加企业面临的融资约束,降低企业的效率投资,进而抑制企业的ESG表现。

关键词：贸易政策不确定性 ESG 融资约束

Study of thermal decoherence of harmonic oscillators

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原子与分子物理学报 2025年第5期42卷 108-114页

作者： LI Jian ZHOU Gao-liang YAN Zheng-Xin LIU Wei WANG Zhao-Qi College of Science Xi’an University of Science and TechnologyXi’an 710054China

The thermal decoherence of harmonic oscillators is investigated *** quantum system presented here is a one-dimensional oscillator with angular frequency,which is surrounded by a thermal bath of environmental *** are various environmental oscillators with different angular frequency(below an ultraviolet cutoff).At the beginning,the quantum system is a pure state and the environmental oscillators are in thermodynamic equilibrium with *** a period,the system-environment interactions inspire significant decoherence of the quantum *** decoherence is displayed by explicit calculations of the purity and von Neumann entropy of the quantum *** is worth noting that the decoherence could be significant even in the weak coupling and low temperature case due to the large amount of environmental degrees of *** the decoherence process is inspired between the quantum system and an ordinary thermal environment here,the thermal decoherence result is quite general.

关键词： Quantum decoherence Grand canonical ensemble Oscillators

参与社区居家养老服务对老年人生理健康的影响

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太原学院学报（社会科学版） 2025年第1期26卷 34-43页

作者：梁钰可欣黑龙江省社会科学院政治学研究所黑龙江哈尔滨150028

保证身体健康是老年人享受幸福晚年生活的基础。基于中国健康与养老追踪调查(CHARLS)2018年的数据,运用logit回归模型探究60~100岁老年人参与社区居家养老服务对其生理健康水平的影响效应并进行异质性分析,通过倾向得分匹配法(PSM)对基... 详细信息

保证身体健康是老年人享受幸福晚年生活的基础。基于中国健康与养老追踪调查(CHARLS)2018年的数据,运用logit回归模型探究60~100岁老年人参与社区居家养老服务对其生理健康水平的影响效应并进行异质性分析,通过倾向得分匹配法(PSM)对基准回归的内生性问题进行补充验证。主要结论有:(1)参与社区居家养老服务显著改善了老年人自评健康和工具性日常生活活动能力。(2)社区居家养老服务对患慢性病样本病情的缓解和控制有显著作用。(3)异质性检验表明,社区居家养老服务对60~75岁、受教育水平较低、农村地区老人的生理健康改善作用更为显著。上述发现表明:应持续推广普惠性的居家或社区养老服务,弥补区域和群体间差异,同时大力推动医养结合养老服务发展,提升老年人整体健康水平。

关键词：老年健康社区居家养老服务慢性病倾向得分匹配

Inverse Lyapunov Theorem for Linear Time Invariant Fractional Order Systems

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Journal of Systems Science & Complexity 2019年第6期32卷 1544-1559页

作者： liang Shu liang Yinshan Key Laboratory of Knowledge Automation for Industrial Processes of Ministry of Education School of Automation and Electrical EngineeringUniversity of Science and Technology BeijingBeijing 100083China Institute of Information Spreading Engineering Changchun University of TechnologyChangchun 130012China

This paper investigates the inverse Lyapunov theorem for linear time invariant fractional order *** is proved that given any stable linear time invariant fractional order system,there exists a positive definite functional with respect to the system state,and the first order time derivative of that functional is negative definite.A systematic procedure to construct such Lyapunov candidates is provided in terms of some Lyapunov functional equations.

关键词： Fractional order systems infinite-dimensional systems inverse Lyapunov theorem stability criterion

A DEA MODEL FOR IDENTIFYING CRITICAL INPUT-OUTPUT PERFORMANCE MEASURES

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Journal of Systems Science & Complexity 2012年第2期25卷 275-286页

作者： Jie WU liang liang School of Management University of Science and Technology of China

In this paper,the authors propose a new model for identifying the critical input-output combinations for each DMU.A real-world application case of 21 international tourist hotels(ITHs) is used to illustrate the propos... 详细信息

关键词： Data envelopment analysis (DEA) efficiency input-output combination performance.

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一种高精度的RC振荡器电路

半导体技术 2025年第1期50卷 71-76页

作者：张亮王静冯玉明广东齐芯半导体有限公司广东珠海519000

为了给微处理器芯片提供高精度的内部时钟,基于110 nm CMOS工艺设计了一种高精度电阻电容(RC)振荡器电路。通过在振荡器结构中引入充放电电流粗调电路、参考电压细调电路、温度系数调节电路,实现了对振荡器电路的工艺偏差、电压敏感度... 详细信息

为了给微处理器芯片提供高精度的内部时钟,基于110 nm CMOS工艺设计了一种高精度电阻电容(RC)振荡器电路。通过在振荡器结构中引入充放电电流粗调电路、参考电压细调电路、温度系数调节电路,实现了对振荡器电路的工艺偏差、电压敏感度、温度敏感度的有效补偿。细调电路提取与电压、工艺及温度都无关的比例系数作为频率调节因子;温度系数调节电路通过合理匹配使得常温下电阻不受档位变化的影响,改善温度系数的同时提高了档位调节过程中的频率稳定性。芯片实测结果显示,经过粗调、细调和温度系数调节三重校正后,振荡器典型输出频率为8 MHz,在-40~150℃的全温度范围内频率变化小于±0.5%,实现了对RC振荡器电路工艺偏差、电压敏感度、温度敏感度的补偿。

关键词：高精度电阻电容(RC)振荡器电压系数修调温度补偿 CMOS工艺

Analysis and experimental study on resistance-increasing behavior of composite high efficiency autonomous inflow control device

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Petroleum Science 2024年第2期21卷 1290-1304页

作者： liang-liang Dong Yu-Lin Zhang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu610500SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina Oil and Gas Equipment Technology Sharing and Service Platform of Sichuan ProvinceChengdu610500SichuanChina

Bottom water coning is the main reason to reduce the recovery of horizontal bottom water reservoir. By water coning, we mean the oil-water interface changes from a horizontal state to a mound-shaped cone and breaks through to the wellbore. Autonomous inflow control device(AICD) is an important instrument maintain normal production after bottom water coning, however, the resistance increasing ability of the swirl type AICD is insufficient at present, which seriously affects the water control effect. Aiming this problem, this paper designs a multi-stage resistance-increasing and composite type AICD. The separation mechanism of oil-water two phases in this structure, the resistance form of oil-water single phase and the resistance-increasing principle of water phase are analyzed. Establishing the dual-phase multi-stage separation and resistance-increasing model, and verified by measuring the throttling pressure drop and oil-water volume fraction of the AICD, it is found that the composite type AICD has the effect of ICD and AICD at the same time, which can balance the production rate of each well section at the initial stage of production, delay the occurrence of bottom water coning. In the middle and later stages of production, water-blocking can be effectively increased to achieve water control and stable *** structural sensitivity analysis, the influence law of various structural parameters on the water control performance of composite AICD was obtained. The simulation calculation results show that,compared with the existing swirl type AICD, composite AICD has higher sensitivity to moisture content,the water phase throttling pressure drop is increased by 4.5 times on average. The composite AICD is suitable for the entire stage of horizontal well production.

关键词： Water control Flow separation Flow resistance-increasing AICD device Simulation and experiment

Orbitronics for energy-efficient magnetization switching

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Science China(Information Sciences) 2025年第1期 398-399页

作者： Yuxuan YAO Daoqian ZHU Qingtao XIA Jianing liang Yuhao JIANG Zhiyang PENG Jiaxu LI Chen XIAO Renyou XU Wenwen WANG Xiantao SHANG Shiyang LU Dapeng ZHU Hong-Xi LIU Kaihua CAO Weisheng ZHAO Fert Beijing Institute School of Integrated Circuit Science and Engineering Beihang University National Key Lab of Spintronics Institute of International Innovation Beihang University Qingdao Research Institute Beihang University Truth Memory Corporation

Spin-orbit torque （SOT）,as a promising writing method for magnetic random-access memory （MRAM）,has garnered widespread interest for over a decade [1].Heavy metals,such as β-W,have been broadly adopted as spin current sources,but suffer from phase change at a limited thickness,resulting in a dramatic reduction of the charge-tospin conversion efficiency θSH[2].The thickness limitation leads to stringent etching conditions and large distribution among devices,posing challenges for simultaneously satisfying SOT efficiency,etching-stop margins,and back-end-ofline （BEOL） compatibility.

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A new mechanism of waves-matter interaction

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Science China(Physics,Mechanics & Astronomy) 2020年第11期63卷 126-127页

作者： Bin liang Institute of Acoustics and Department of Physics Nanjing UniversityNanjing 210093China

In ancient Rome,architects mastered the skills of using vases and walls to control sounds in a *** physics,such a principle applies not only to acoustics but also to *** on the deep understanding of radiation processes,a notion has long been accepted,that is,an emitter interacts with the photonic eigenstates of its surrounding environment.

关键词： acoustics walls interaction