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Adjustment mechanism of blasting dynamic-static action in the water decoupling charge
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作者 Hao Zhang Xueyang Xing +3 位作者 Yiteng Du Tingchun Li Jianxin Yu Qingwen Zhu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第6期821-836,共16页
Water decoupling charge blasting excels in rock breaking,relying on its uniform pressure transmission and low energy dissipation.The water decoupling coefficients can adjust the contributions of the stress wave and qu... Water decoupling charge blasting excels in rock breaking,relying on its uniform pressure transmission and low energy dissipation.The water decoupling coefficients can adjust the contributions of the stress wave and quasi-static pressure.However,the quantitative relationship between the two contributions is unclear,and it is difficult to provide reasonable theoretical support for the design of water decoupling blasting.In this study,a theoretical model of blasting fracturing partitioning is established.The mechanical mechanism and determination method of the optimal decoupling coefficient are obtained.The reliability is verified through model experiments and a field test.The results show that with the increasing of decoupling coefficient,the rock breaking ability of blasting dynamic action decreases,while quasi-static action increases and then decreases.The ability of quasi-static action to wedge into cracks changes due to the spatial adjustment of the blast hole and crushed zone.The quasi-static action plays a leading role in the fracturing range,determining an optimal decoupling coefficient.The optimal water decoupling coefficient is not a fixed value,which can be obtained by the proposed theoretical model.Compared with the theoretical results,the maximum error in the model experiment results is 8.03%,and the error in the field test result is 3.04%. 展开更多
关键词 Water decoupling blasting Blasting dynamic-static action Optimal decoupling coefficient adjustment mechanism
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The carbon border adjustment mechanism is inefficient in addressing carbon leakage and results in unfair welfare losses 被引量:2
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作者 Xinlu Sun Zhifu Mi +2 位作者 Lu Cheng D'Maris Coffman Yu Liu 《Fundamental Research》 CAS CSCD 2024年第3期660-670,共11页
The European Commission has proposed a Carbon Border Adjustment Mechanism(CBAM)to reduce carbon leakage and create a level playing field for its domestic products and imported goods.Nevertheless,the effectiveness of t... The European Commission has proposed a Carbon Border Adjustment Mechanism(CBAM)to reduce carbon leakage and create a level playing field for its domestic products and imported goods.Nevertheless,the effectiveness of the proposal remains unclear,especially when it triggers threats of retaliation from trading partners of the European Union.We apply a Computable General Equilibrium model-Global Trade Analysis Project-to assess the economic and environmental impacts of different CBAM schemes.Here we show that the effectiveness of the CBAM to address carbon leakage risks is rather limited,and the CBAM raises concerns over global welfare costs,Correct to Gross Domestic Product(GDP)losses,and violation of equality principles.Trade retaliation leads to multiplied welfare losses,which would mostly be borne by poor countries.Our results question the carbon leakage reduction effect of a unilateral trade policy and suggest that climate change mitigation still needs to be performed within the framework of international cooperation. 展开更多
关键词 Carbon border adjustment mechanism Carbon leakage Climate change mitigation Floorcarbon price Trade retaliation
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Response Mechanism of Plants to Drought Stress
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作者 Pei GAO Yuhua MA 《Plant Diseases and Pests》 CAS 2023年第5期30-34,共5页
Drought stress is an important factor affecting plant growth and development.It will provide a theoretical basis for cultivating new stress-resistant varieties and improving water utilization rate of plants by studyin... Drought stress is an important factor affecting plant growth and development.It will provide a theoretical basis for cultivating new stress-resistant varieties and improving water utilization rate of plants by studying the regulation mechanism of osmotic adjustment and water transportation under drought stress,and understanding the physiological and biochemical characteristics and stress resistance mechanism. 展开更多
关键词 Plant gene Drought stress Regulation mechanism Osmotic adjustment substance Water transportation
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Could the EU carbon border adjustment mechanism promote climate mitigation?An economy-wide analysis
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作者 Kun ZHANG Yun-Fei YAO +3 位作者 Xiang-Yan QIAN Yu-Fei ZHANG Qiao-Mei LIANG Yi-Ming WEI 《Advances in Climate Change Research》 SCIE CSCD 2024年第3期557-571,共15页
Due to concerns about carbon leakage and sectoral competitiveness,the European Union(EU)proposed implementing the carbon border adjustment mechanism(CBAM).The effectiveness and potential negative consequences of CBAM ... Due to concerns about carbon leakage and sectoral competitiveness,the European Union(EU)proposed implementing the carbon border adjustment mechanism(CBAM).The effectiveness and potential negative consequences of CBAM have aroused extensive discussion.From the perspective of the economy-wide analysis,this study uses a global computable general equilibrium model to explore the rationality of CBAM from the aspects of socioeconomic impact and the effects of promoting climate mitigation.Furthermore,the potential alternative mechanism of CBAM is proposed.The results show that CBAM can reduce the EU's gross domestic product(GDP)loss;however,the GDP loss in all other regions increases.Moreover,CBAM raises household welfare losses in most regions,including the EU.Second,although CBAM can reduce the marginal abatement cost in eight regions,it comes at the cost of greater economic losses.Furthermore,the economic and household welfare cost of raising emissions reduction targets in regions like the USA and Japan is substantially higher than the impact of passively accepting the CBAM;therefore,CBAM's ability to drive ambitious emission reduction initiatives may be limited.Finally,for the potential alternative mechanism,from the perspective of reducing economic cost and household welfare losses,the EU could implement domestic tax cuts in the short-term and promote global unified carbon pricing in the long-term. 展开更多
关键词 Border adjustment mechanism Computable general equilibrium model Carbon price Climate policy Global carbon pricing
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Dental Treatment Using Quantum Mechanics for Knee Joint Pain
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作者 Yoshiro Fujii 《Natural Science》 2024年第9期146-149,共4页
In clinical practice, dentists sometimes encounter phenomena that cannot be explained by modern western medical concepts;for example, the patient’s medical symptoms improve by bringing medicines or dentures close to ... In clinical practice, dentists sometimes encounter phenomena that cannot be explained by modern western medical concepts;for example, the patient’s medical symptoms improve by bringing medicines or dentures close to the body. Although it seems difficult to completely elucidate the mechanism through modern western medicine, it can be explained using quantum mechanics. The quantum, the smallest unit of matter composition, exhibits wave-particle duality. The fact that symptoms can be improved simply by bringing dentures or medicines closer to the body indicates that the waves emitted by dentures or medicines interfere with the pathological waves emitted by the pathological site. Thus, the pathological waves are deformed and lead to a change in symptoms. In this way, quantum theory can explain phenomena that are difficult to elucidate in conventional medicine, which are encountered in clinical practice. So far, the author has presented a case of difficulty in raising the upper limb where the symptoms improved without the need for dentures in the mouth by adjusting the dentures outside the mouth. This time, the author would like to introduce a case which the patient’s knee pain improved by adjusting the dentures outside the mouth. 展开更多
关键词 Denture adjustment Knee Joint Pain Quantum mechanics Wave Interference The Bi-Digital O-Ring Test
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Controlling chaos using Takagi-Sugeno fuzzy model and adaptive adjustment 被引量:3
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作者 郑永爱 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第11期2549-2552,共4页
In this paper, an approach to the control of continuous-time chaotic systems is proposed using the Takagi-Sugeno (TS) fuzzy model and adaptive adjustment. Sufficient conditions are derived to guarantee chaos control... In this paper, an approach to the control of continuous-time chaotic systems is proposed using the Takagi-Sugeno (TS) fuzzy model and adaptive adjustment. Sufficient conditions are derived to guarantee chaos control from Lyapunov stability theory. The proposed approach offers a systematic design procedure for stabilizing a large class of chaotic systems in the literature about chaos research. The simulation results on Rossler's system verify the effectiveness of the proposed methods. 展开更多
关键词 controlling chaos adaptive adjustment mechanism Rossler system TS fuzzy model
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An Equivalent Substitute Strategy for Constructing 3D Ordered Porous Carbon Foams and Their Electromagnetic Attenuation Mechanism 被引量:6
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作者 Meng Zhang Hailong Ling +11 位作者 Ting Wang Yingjing Jiang Guanying Song Wen Zhao Laibin Zhao Tingting Cheng Yuxin Xie Yuying Guo Wenxin Zhao Liying Yuan Alan Meng Zhenjiang Li 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第10期15-35,共21页
Three-dimensional(3D)ordered porous carbon is generally believed to be a promising electromagnetic wave(EMW)absorbing material.However,most research works targeted performance improvement of 3D ordered porous carbon,a... Three-dimensional(3D)ordered porous carbon is generally believed to be a promising electromagnetic wave(EMW)absorbing material.However,most research works targeted performance improvement of 3D ordered porous carbon,and the specific attenuation mechanism is still ambiguous.Therefore,in this work,a novel ultra-light egg-derived porous carbon foam(EDCF)structure has been successfully constructed by a simple carbonization combined with the silica microsphere template-etching process.Based on an equivalent substitute strategy,the influence of pore volume and specific surface area on the electromagnetic parameters and EMW absorption properties of the EDCF products was confirmed respectively by adjusting the addition content and diameter of silica microspheres.As a primary attenuation mode,the dielectric loss originates from the comprehensive effect of conduction loss and polarization loss in S-band and C band,and the value is dominated by polarization loss in X band and Ku band,which is obviously greater than that of conduction loss.Furthermore,in all samples,the largest effective absorption bandwidth of EDCF-3 is 7.12 GHz under the thickness of 2.13 mm with the filling content of approximately 5 wt%,covering the whole Ku band.Meanwhile,the EDCF-7 sample with optimized pore volume and specific surface area achieves minimum reflection loss(RL_(min))of−58.08 dB at 16.86 GHz while the thickness is 1.27 mm.The outstanding research results not only provide a novel insight into enhancement of EMW absorption properties but also clarify the dominant dissipation mechanism for the porous carbon-based absorber from the perspective of objective experiments. 展开更多
关键词 Porous carbon foam Electromagnetic wave absorption adjustable pore structure Polarization loss Attenuation mechanism
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Effect of Facet Displacement on Radiation Field and Its Application for Panel Adjustment of Large Reflector Antenna 被引量:3
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作者 Wei WANG Peiyuan LIAN +2 位作者 Shuxin ZHANG Binbin XIANG Qian XU 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期578-586,共9页
Large reflector antennas are widely used in radars, satellite communication, radio astronomy, and so on. The rapid developments in these fields have created demands for development of better performance and higher sur... Large reflector antennas are widely used in radars, satellite communication, radio astronomy, and so on. The rapid developments in these fields have created demands for development of better performance and higher surface accuracy. However, low accuracy and low effi- ciency are the common disadvantages for traditional panel alignment and adjustment. In order to improve the surface accuracy of large reflector antenna, a new method is pre- sented to determinate panel adjustment values from far field pattern. Based on the method of Physical Optics (PO), the effect of panel facet displacement on radiation field value is derived. Then the linear system is constructed between panel adjustment vector and far field pattern. Using the method of Singular Value Decomposition (SVD), the adjustment value for all panel adjustors are obtained by solving the linear equations. An experiment is conducted on a 3.7 m reflector antenna with 12 segmented panels. The results of simulation and test are similar, which shows that the presented method is feasible. Moreover, thediscussion about validation shows that the method can be used for many cases of reflector shape. The proposed research provides the instruction to adjust surface panels efficiently and accurately. 展开更多
关键词 Reflector antennas Surface accuracy -Radiation field - Reflector antenna mechanical factors Electromechanical effects - Panel adjustment - Singularvalue decomposition (SVD)
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Enrichment Mechanism and Prospects of Deep Oil and Gas 被引量:4
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作者 HAO Fang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第3期742-756,共15页
With the deepening of oil and gas exploration,the importance of depth is increasingly highlighted.The risk of preservation of storage space in deep reservoirs is greater than that in shallow and medium layers.Deep lay... With the deepening of oil and gas exploration,the importance of depth is increasingly highlighted.The risk of preservation of storage space in deep reservoirs is greater than that in shallow and medium layers.Deep layers mean older strata,more complex structural evolution and more complex hydrocarbon accumulation processes,and even adjustment and transformation of oil and gas reservoirs.This paper systematically investigates the current status and research progress of deep oil and gas exploration around the world and looks forward to the future research focus of deep oil and gas.In the deep,especially the ultra-deep layers,carbonate reservoirs play a more important role than clastic rocks.Karst,fault-karst and dolomite reservoirs are the main types of deep and ultra-deep reservoirs.The common feature of most deep large and medium-sized oil and gas reservoirs is that they formed in the early with shallow depth.Fault activity and evolution of trap highs are the main ways to cause physical adjustment of oil and gas reservoirs.Crude oil cracking and thermochemical sulfate reduction(TSR)are the main chemical modification effects in the reservoir.Large-scale high-quality dolomite reservoirs is the main direction of deep oil and gas exploration.Accurate identification of oil and gas charging,adjustment and reformation processes is the key to understanding deep oil and gas distribution.High-precision detection technology and high-precision dating technology are an important guarantee for deep oil and gas research. 展开更多
关键词 deep oil and gas carbonate reservoir main accumulation period reservoir adjustment and reconstruction enrichment mechanism
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Enabling dendrite-free charging for lithium batteries based on transport-reaction competition mechanism in CHAIN framework 被引量:1
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作者 Lisheng Zhang Siyan Chen +6 位作者 Wentao Wang Hanqing Yu Haicheng Xie Huizhi Wang Shichun Yang Cheng Zhang Xinhua Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第12期408-421,I0011,共15页
Worldwide trends in mobile electrification will skyrocket demands for lithium-based battery production,driven by the popularity of electric vehicles.However,both lithium metal batteries and lithium ion batteries face ... Worldwide trends in mobile electrification will skyrocket demands for lithium-based battery production,driven by the popularity of electric vehicles.However,both lithium metal batteries and lithium ion batteries face severe safety issues due to dendrite nucleation and growth process.Li deposition is significantly influenced by interfacial factors and charging conditions.In this paper,an electrochemical model considering the internal and external factors is proposed based on Monte Carlo method.The influence of internal solid electrolyte interphase(SEI)porosity,thickness and the external conditions on dendrite growth process is systematically described.The simulation results support that the three factors investigated in this model could synergistically regulate the dendrite growth process.Three competition mechanisms are proposed to tailor lithium deposition for Li-based batteries and numerical solutions for variation pattern of dendrite growth with time are fitted.A three-step process describing kinetic process of lithium deposition is proposed.To achieve dendrite-free charging process,charging strategies and emerging materials design should be considered,including physicochemical materials engineering,artificial SEI,and design for dynamic safety boundary.This work could contribute to the foundation for insights of Li deposition mechanism,which is promising to provide guidelines for next-generation high-energy-density and safe batteries in CHAIN framework. 展开更多
关键词 Li-based batteries Model Dendrite growth Synergistic adjustment Competition mechanism
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Kinematic Calibration of Asymmetricly Actuated 6-DOF 3-PPPS Parallel Mechanism
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作者 Chen Lei Huang Xiang +1 位作者 Ma Zhiqiang Li Shuanggao 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第3期294-300,共7页
An asymmetric actuated 3-PPPS parallel mechanism was analyzed in its application to an aircraft wing adjustment process.The posture alignment precision at the wing ends was enhanced with a kinematic calibration method... An asymmetric actuated 3-PPPS parallel mechanism was analyzed in its application to an aircraft wing adjustment process.The posture alignment precision at the wing ends was enhanced with a kinematic calibration method.A constraint equation was built based on a constraint condition that distances among spherical joints of the mechanism were constant,and further eight groups of analytic forward solutions of all poses of the mechanism were solved.An inverse equation of the posture alignment displacements of aircraft wing parts was built based on space vector chains,and a mapping equation of the pose and geometric errors of the posture alignment mechanism containing 39 error sources was derived by differentiating the kinematic equation of the mechanism.After kinematic calibration experiments,the maximum position error of the posture alignment platform dropped from 2.67 mm to 0.82 mm,the maximum angle error decreased from 0.481° to 0.167°,and the posture alignment precision of the aircraft wing end was improved. 展开更多
关键词 aircraft wing adjustment parallel mechanism forward numerical solution laser tracker kinematic calibration
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Which sectors should be covered by the EU Carbon Border Adjustment Mechanism?
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作者 Bo-Qiang LIN Heng-Song ZHAO 《Advances in Climate Change Research》 SCIE CSCD 2023年第6期952-962,共11页
The European Union(EU)is developing the Carbon Border Adjustment Mechanism(CBAM)to address carbon leakage in international trade.However,the EU has paid inadequate attention to input-output linkages,specifically those... The European Union(EU)is developing the Carbon Border Adjustment Mechanism(CBAM)to address carbon leakage in international trade.However,the EU has paid inadequate attention to input-output linkages,specifically those in the steel,aluminum,and fertiliser industries.This study aims to identify priority sectors eligible for initial regulation within the emissions-intensive trade-exposed(EITE)industries based on input-output linkages and compare its impacts with the current CBAM sector coverage.This study constructs a Global Production Network(GPN)and Carbon Flow Network(CFN)to present the input trade and embodied carbon flows for the EITE industries.This study highlights the role of the EITE industries as influential nodes in the production network and how the EITE industries in the EU contribute to carbon emissions.To improve the economy and political acceptability,CABM should cover four priority sectors with low economic impacts but a crucial role in reducing emissions,such as plastics,phosphorus fertiliser,aluminum,and copper industry. 展开更多
关键词 Carbon Border adjustment mechanism Input-output analysis Hypothetical extraction method Production network Embodied carbon emissions
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水利工程供水价格常态化调整机制探索
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作者 杨柠 李淼 +4 位作者 郭悦 姚玉琴 高玉屏 刘品 王小娜 《水利发展研究》 2024年第1期66-69,共4页
为纠正水利工程供水成本长期大幅偏离价格,激励水利工程单位主动强化成本管理,需要建立水利工程供水价格常态化调整机制。水价调整既要考虑外围价格环境的传导作用引起的成本刚性增长,也要考虑供水服务质量和管理单位成本控制因素,构建... 为纠正水利工程供水成本长期大幅偏离价格,激励水利工程单位主动强化成本管理,需要建立水利工程供水价格常态化调整机制。水价调整既要考虑外围价格环境的传导作用引起的成本刚性增长,也要考虑供水服务质量和管理单位成本控制因素,构建水利工程供水价格与生产管理要素价格的联动机制。 展开更多
关键词 供水价格 调整要素 调整模型 调整机制
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城乡居民基本养老保险的制度优化研究 被引量:1
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作者 林闽钢 曹思远 《行政管理改革》 北大核心 2024年第3期16-25,共10页
目前,我国城乡居民养老保险制度进入“从有到好”的新阶段,制度的优化成为关键问题。城乡居民养老保险制度作为“保基本”的社会保险制度,当前面临的主要问题表现在:城乡居民养老保险的待遇水平低、农村老龄人口基数大、管理层级低,公... 目前,我国城乡居民养老保险制度进入“从有到好”的新阶段,制度的优化成为关键问题。城乡居民养老保险制度作为“保基本”的社会保险制度,当前面临的主要问题表现在:城乡居民养老保险的待遇水平低、农村老龄人口基数大、管理层级低,公平性和可持续性发展问题凸显。为此,从保险待遇、保险结构和经办服务三个方面提出六条优化措施:提高城乡居民参保的最低缴费档次标准;设立城乡居民基本养老保险待遇的增长机制;引入集体补助促进保险缴费结构优化;引导灵活就业人员、失地农民等劳动年龄段城乡居民参加企业职工基本养老保险;探索城乡居民基本养老保险参保者转为企业职工基本养老保险参保者的分流途径和方法;探索提高城乡居民养老保险的管理层级。 展开更多
关键词 城乡居民基本养老保险 待遇调整机制 制度优化
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无缝内衣机调密机构动力学特性研究
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作者 彭来湖 胡义亮 +1 位作者 戴宁 胡旭东 《针织工业》 北大核心 2024年第4期27-30,共4页
针对现有无缝内衣机中密度电动机输出力矩不稳定、测量困难等问题,研究无缝内衣机调密机构动力学特性。结合无缝内衣机成圈及密度调节工艺,建立调密机构三维模型,得到三角滑块推力与电动机转矩间数学关系,运用SolidWorks Motion模块对... 针对现有无缝内衣机中密度电动机输出力矩不稳定、测量困难等问题,研究无缝内衣机调密机构动力学特性。结合无缝内衣机成圈及密度调节工艺,建立调密机构三维模型,得到三角滑块推力与电动机转矩间数学关系,运用SolidWorks Motion模块对调密机构进行动力学仿真。搭建调密机构力学测试平台,将测试推力值代入推力与电动机转矩间数学关系计算。结果表明:测试结果与仿真数据相差3.81%,证明理论及建模仿真正确性,给现有无缝内衣机密度调节控制方案中电动机输出力矩控制提供参考。 展开更多
关键词 无缝内衣机 密度调节机构 动力学分析 电动机力矩
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欧美碳关税对我国的挑战及对策探究——基于“碳边境调节机制”与“清洁竞争法案”的比较 被引量:1
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作者 林国建 《莆田学院学报》 2024年第1期56-62,共7页
简要阐述了欧盟“碳边境调节机制”与美国“清洁竞争法案”的发展历程及现状,并对两者进行了比较。欧美碳关税的实施将对我国的贸易体系产生一定的冲击。在“双碳”目标的指引下,我国政府和企业应该积极应对:主动开展国际交流合作、坚... 简要阐述了欧盟“碳边境调节机制”与美国“清洁竞争法案”的发展历程及现状,并对两者进行了比较。欧美碳关税的实施将对我国的贸易体系产生一定的冲击。在“双碳”目标的指引下,我国政府和企业应该积极应对:主动开展国际交流合作、坚决抵制单边贸易保护,发展低碳技术、大力降低碳含量,增加碳排放成本、提升碳减排效率,加强碳足迹管理、构建产品碳排放核算体系,锚定“双碳”目标,坚定不移走绿色低碳的高质量发展道路。 展开更多
关键词 碳边境调节机制 清洁竞争法案 碳关税 碳含量 碳价格
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自适应调节重心林间运输车设计与仿真
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作者 王慧 安洋 +1 位作者 崔生乐 杨春梅 《中国农机化学报》 北大核心 2024年第3期148-155,共8页
为提高运输车在林间的工作效率,研究设计一款能够远程遥控且能根据自身运动姿态自动调节重心的小型林间履带式运输车。通过理论计算完成整车各部分机构的设计,分析整车在可调节重心机构调控下的通过性,确定可调节重心机构的控制策略,并... 为提高运输车在林间的工作效率,研究设计一款能够远程遥控且能根据自身运动姿态自动调节重心的小型林间履带式运输车。通过理论计算完成整车各部分机构的设计,分析整车在可调节重心机构调控下的通过性,确定可调节重心机构的控制策略,并利用Recurdyn软件对整机进行通过性模拟仿真。仿真结果表明,经过调控重心后,整机的通过性得到有效提升,整机上坡的极限角度提高17.9%,横坡的极限角度提高18.3%,极限越障高度提高18.7%,跨壕极限宽度提高13.9%。 展开更多
关键词 林地环境 林间履带式运输机 可调节重心机构 通过性 RECURDYN
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美联储调息与人民币汇率变化研究
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作者 江世银 刘莹 李洁 《金融教育研究》 2024年第4期3-13,共11页
为改善高通货膨胀的经济环境,2022年美联储宣布加息,不仅影响美国国内而且影响了包括中国在内的开放型经济国家。为提高实证分析结论的准确性,通过构建VAR模型,以此轮美联储加息为背景,选取2006年1月至2023年8月美元兑人民币汇率以及美... 为改善高通货膨胀的经济环境,2022年美联储宣布加息,不仅影响美国国内而且影响了包括中国在内的开放型经济国家。为提高实证分析结论的准确性,通过构建VAR模型,以此轮美联储加息为背景,选取2006年1月至2023年8月美元兑人民币汇率以及美国联邦基金利率等数据,逐步研究美联储调整利率后部分变量对人民币汇率的影响。研究结果表明,美联储调息的直接影响效果最为显著,且短期的影响效应大于长期。为此,在新发展阶段下,应建立强大的宏观审慎监管体系,适时干预外汇市场,以促进汇率改革与人民币汇率稳定。 展开更多
关键词 美联储调息 人民币汇率 传导机制 防范对策
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气候治理与国际贸易协调视角下欧盟碳边境调节机制的应对
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作者 魏圣香 《上海大学学报(社会科学版)》 北大核心 2024年第5期98-112,共15页
欧盟碳边境调节机制的产品适用范围涵盖了钢铁、电力等传统碳密集型产业,旨在与欧盟碳排放交易机制互为补充,逐步取消免费碳配额,避免碳泄漏。从中国产品出口量及产品结构来看,碳密集型产品与碳边境调节机制高度关联,未来将对中国参与... 欧盟碳边境调节机制的产品适用范围涵盖了钢铁、电力等传统碳密集型产业,旨在与欧盟碳排放交易机制互为补充,逐步取消免费碳配额,避免碳泄漏。从中国产品出口量及产品结构来看,碳密集型产品与碳边境调节机制高度关联,未来将对中国参与全球气候治理及国际贸易竞争力产生较大影响。为了有效应对欧盟碳边境调节机制,中国可等待时机诉诸世界贸易组织争端解决机制,考虑协调环境与贸易的新诸边协议,积极开展环境产品和服务自由化谈判,破除贸易保护主义,推动经济绿色发展。长远来看,中国应主动作为,加快高碳行业绿色转型步伐,建立健全碳排放交易市场与碳税的制度设计,引导自上而下由政府至企业的气候贸易合规管理方案,有效应对气候变化,进一步提升中国产品的国际贸易竞争力。 展开更多
关键词 碳排放 欧盟碳边境调节机制 环境与贸易 气候变化
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全旋转指向式导向钻井工具结构设计与仿真
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作者 张光伟 尹福来 +1 位作者 程礼林 侯朋朋 《机械设计与制造》 北大核心 2024年第5期136-140,共5页
为了提高全旋转指向式导向钻井工具的设计效率,缩短研发周期,笔者首先设计了该钻井工具的导向执行机构,简化导向执行机构的空间机构模型,通过自由度的计算,得出了该机构具有确定的运动。再对该钻井工具的结构组成和导向原理进行分析,得... 为了提高全旋转指向式导向钻井工具的设计效率,缩短研发周期,笔者首先设计了该钻井工具的导向执行机构,简化导向执行机构的空间机构模型,通过自由度的计算,得出了该机构具有确定的运动。再对该钻井工具的结构组成和导向原理进行分析,得到了其导向控制方法是通过控制全旋转指向式导向钻井工具的双偏心环和旋转外套的角位移关系,调节其工具角和工具面角,实现导向钻井。最后利用SolidWorks和ADAMS软件对钻井工具虚拟样机进行三维实体建模及运动仿真,仿真结果表明该钻井工具可以实现工具面角(0~360)°和工具角(0~5)°的无级调节,验证了所设计的全旋转指向式导向钻井工具结构和导向原理的可行性,为原理样机的加工奠定了基础。 展开更多
关键词 导向钻井工具 偏置机构 导向调节 运动仿真 虚拟样机
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