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Approach to dynamic error suppression in ground vehicle gravimetry based on external velocity compensation
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作者 LI Xinyu ZHOU Zhaofa +2 位作者 ZHANG Zhili CHANG Zhenjun HAO Shiwen 《Journal of Systems Engineering and Electronics》 2025年第2期580-596,共17页
The process of ground vehicle dynamic gravimetry is inevitably affected by the carrier’s maneuvering acceleration,which makes the result contain a large amount of dynamic error.In this paper,we propose a dynamic erro... The process of ground vehicle dynamic gravimetry is inevitably affected by the carrier’s maneuvering acceleration,which makes the result contain a large amount of dynamic error.In this paper,we propose a dynamic error suppression method of gravimetry based on the high-precision acquisition of external velocity for compensating the horizontal error of the inertial plat-form.On the basis of platform gravity measurement,firstly,the dynamic performance of the system is enhanced by optimizing the horizontal damping network of the inertial platform and selecting its parameter.Secondly,an improved federal Kalman filtering algorithm and a fault diagnosis method are designed using strapdown inertial navigation system(SINS),odometer(OD),and laser Doppler velocimeter(LDV).Simulation validates that these methods can improve the accuracy and robustness of the external velocity acquisition.Three survey lines are selected in Tianjin,China,for the gravimetry experiments with different maneuvering levels,and the results demonstrate that after dynamic error suppression,the internal coincidence accuracies of smooth and uniform operation,obvious acceleration and deceleration operation,and high-dynamic operation are improved by 70.2%,73.6%,and 77.9%to reach 0.81 mGal,1.30 mGal,and 1.94 mGal,respectively,and the external coinci-dence accuracies during smooth and uniform operation are improved by 48.6%up to 1.66 mGal.It is shown that the pro-posed method can effectively suppress the dynamic error,and that the accuracy improvement increases with carrier maneuver-ability.However,the amount of residual error that can not be entirely eliminated increases as well,so the ground vehicle dynamic gravimetry should be maintained in the carrier for smooth and uniform operation. 展开更多
关键词 ground vehicle gravimetry dynamic error suppres-sion external velocity compensation federal Kalman filter fault diagnosis and isolation
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Limit equilibrium stability analysis of slopes under external loads 被引量:5
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作者 DENG Dong-ping ZHAO Lian-heng LI Liang 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第9期2382-2396,共15页
Two calculation modes for the effect of external load on slope stability, i.e., mode I in which the external load is thought to act on slope surface, and mode II in which the external load is thought to act on slip su... Two calculation modes for the effect of external load on slope stability, i.e., mode I in which the external load is thought to act on slope surface, and mode II in which the external load is thought to act on slip surface along the force action line, were considered. Meanwhile, four basic distribution patterns of external load were used, of which complex external loads could be composed. In analysis process, several limit equilibrium methods, such as Swedish method, simplified Bishop method, simplified Janbu method, Spencer method, Morgenstern-Price(M-P) method, Sarma method, and unbalanced thrust method, were also adopted to contrast their differences in slope stability under the external load. According to parametric analysis, some conclusions can be obtained as follows:(1) The external load, with the large magnitude, small inclination angle, and acting position close to the slope toe,has more positive effect on slope stability;(2) The results calculated using modes I and II of external load are similar, indicating that the calculation mode of external load has little influence on slope stability;(3) If different patterns of external loads are equivalent to each other, their slope stability under these external loads are the same, and if not, the external load leads to the better slope stability,as action position of the resultant force for external load is closer to the lower sliding point of slip surface. 展开更多
关键词 slope stability calculation mode of external load distribution pattern of external load limit equilibrium slip surface factor of safety (FOS)
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PD-type iterative learning control for nonlinear time-delay system with external disturbance 被引量:12
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作者 Zhang Baolin Tang Gongyou Zheng Shi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期600-605,共6页
The PD-type iterative learning control design of a class of affine nonlinear time-delay systems with external disturbances is considered. Sufficient conditions guaranteeing the convergence of the n-norm of the trackin... The PD-type iterative learning control design of a class of affine nonlinear time-delay systems with external disturbances is considered. Sufficient conditions guaranteeing the convergence of the n-norm of the tracking error are derived. It is shown that the system outputs can be guaranteed to converge to desired trajectories in the absence of external disturbances and output measurement noises. And in the presence of state disturbances and measurement noises, the tracking error will be bounded uniformly. A numerical simulation example is presented to validate the effectiveness of the proposed scheme. 展开更多
关键词 time-delay system nonlinear system iterative learning control CONVERGENCE external disturbance.
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The detrimental effect of autofrettage on externally cracked modern tank gun barrels 被引量:2
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作者 M.Perl T.Saley 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第2期146-153,共8页
Overstraining gun tubes has a twofold advantage. First, it enables the increase of the Safe Maximum Pressure(SMP) in the tube, resulting in a higher muzzle velocity which extends the gun's range and its projectile... Overstraining gun tubes has a twofold advantage. First, it enables the increase of the Safe Maximum Pressure(SMP) in the tube, resulting in a higher muzzle velocity which extends the gun's range and its projectile kinetic energy. Second, it reduces the tube's susceptibility to internal cracking which prolongs its fatigue life. Unfortunately, autofrettage also bears an inherent detrimental effect as it considerably increases the tensile hoop stress at the outer portion of the barrel's wall, which enhances external cracking of the tube by increasing the prevailing Stress Intensity Factor(SIF). In order to quantify this disadvantageous effect, 3-D Mode I SIFs distributions along the front of a single external radial semielliptical crack initiating from the outer surface of an autofrettaged modern gun barrel, overstrained by either the Swage or the Hydraulic autofrettage processes, are evaluated. The analysis is performed by the finite element(FE) method, using singular elements along the crack front. Innovative residual stress fields(RSFs), incorporating the Bauschinger effect for both types of autofrettage are applied to the barrel.Hill's [1] RSF is also applied to the tube for comparison reasons. All three RSFs are incorporated in the FE analysis, using equivalent temperature fields, Values for K_(IA)-the SIF resulting from the tensile residual stresses induced by autofrettage are evaluated for: a typical barrel of radii ratio R_o/R_i = 2, crack depth to wall-thickness ratios(a/t = 0.005-0.1),crack ellipticities(a/c = 0.2-1.0),and five levels of Swage,Hydraulic and Hill's autofrettage(e = 40%,60%,70%,80%,and 100%). In total,375 different 3-D cases are analyzed. The analysis demonstrates undoubtedly the detrimental effect of all types of autofrettage in increasing the prevailing effective stress intensity factor of external cracks, resulting in crack initiation enhancement and crack growth rate acceleration which considerably shortens the total fatigue life of the barrel. Nonetheless, the detrimental effect is autofrettage-type dependent. Swage and Hydraulic autofrettage RSFs differ substantially from each other. The disadvantageous effect of Swage autofrettage is much greater than that resulting from Hydraulic autofrettage. The results also emphasize the significance of the Bauschinger effect and the importance of the 3-D analysis. 展开更多
关键词 GUN BARREL Swage and HYDRAULIC AUTOFRETTAGE external CRACK 3-D Finite element
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Lubrication characteristics of external return spherical hinge pair of axial piston pump or motor under combined action of inclination and offset distance 被引量:4
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作者 WANG Lei DENG Hai-shun +2 位作者 GUO Yong-chun WANG Chuan-li HU Cong 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第8期2375-2393,共19页
External return mechanism is a mechanical structure applied to axial piston pumps.To study its lubrication characteristics,the Reynolds equation applied to an external return spherical hinge pair was deduced based on ... External return mechanism is a mechanical structure applied to axial piston pumps.To study its lubrication characteristics,the Reynolds equation applied to an external return spherical hinge pair was deduced based on the vector equation of relative-motion velocity of the external return spherical hinge pair under the influence of external swash plate inclination and offset distance.The results show that the total friction,axial leakage flow,and maximum value of the maximum oil-film pressure increase with increasing pump-shaft speed and decrease with increasing offset distance in one working cycle when the external-swash-plate inclination is constant.However,the varying offset distance has little effect on the axial leakage flow.The maximum value of the maximum oil-film pressure decreases with increasing external-swash-plate inclination and the total leakage flow increases with increasing external-swash-plate inclination in one working cycle when the offset distance is constant.It can be seen that the abovementioned parameters are important factors that affect the lubrication characteristics of external return spherical hinge pairs.Therefore,the complex effects of different coupling parameters should be comprehensively considered in the design of the external return mechanism. 展开更多
关键词 axial piston motor or pump external return mechanism external swash plate inclination offset distance lubrication performance
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Impact of light-weight external thermal insulation materials on building surrounding thermal environment in summer 被引量:6
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作者 李楠 罗国志 +1 位作者 李百战 黄彦祺 《Journal of Central South University》 SCIE EI CAS 2012年第6期1639-1644,共6页
The method for calculating wall surface heat storage coefficient was introduced,and the coefficients of several common walls with light-weight external thermal insulation materials and the traditional solid clay brick... The method for calculating wall surface heat storage coefficient was introduced,and the coefficients of several common walls with light-weight external thermal insulation materials and the traditional solid clay brick wall were calculated.In order to study the impact of light-weight external thermal insulation materials,a contrasting experiment was carried out between an external insulated room and an uninsulated room in August,2010,in Chongqing,China.The result shows that outside surface heat storage coefficient of the insulated wall is much less than that of the traditional wall.However,during sunny time,the surface temperature of external walls of the insulated room is obviously higher than that of the uninsulated room.In different orientations,due to different amounts of solar radiation and being irradiated in different time,the contrasting temperature difference(CTD) appears different regularity.In a word,using light-weight external thermal insulation materials has a negative impact on building surrounding thermal environment and people's health.Finally,some suggestions on how to eliminate the impact,such as improving the surface condition of the building envelop,and plating vertical greening,are put forward. 展开更多
关键词 surface heat storage coefficient external thermal insulation BUILDING thermal environment building envelop
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External blast flow field evolution and response mechanism of single-layer reticulated dome structure 被引量:5
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作者 Shao-bo Qi Guang-yan Huang +1 位作者 Xu-dong Zhi Feng Fan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期241-253,共13页
Single-layer reticulated dome structure are commonly high-profile building in the public and can be attractive targets for terrorist bombings,so the public can benefit from enhanced safety with a stronger understandin... Single-layer reticulated dome structure are commonly high-profile building in the public and can be attractive targets for terrorist bombings,so the public can benefit from enhanced safety with a stronger understanding of the behavior of single-layer reticulated dome structure under explosion.This paper investigates the fluid-structure interaction process and the dynamic response performance of the singlelayer reticulated dome under external blast load.Both experimental and numerical results shown that structural deformation is remarkably delayed compared with the velocity of blast wave,which advises the dynamic response of large-span reticulated dome structure has a negligible effect on the blast wave propagation under explosion.Four failure modes are identified by comparing the plastic development of each ring and the residual spatial geometric of the structure,i.e.,minor vibration,local depression,severe damage,and overall collapse.The plastic deformation energy and the displacement potential energy of the structure are the main consumers of the blast energy.In addition,the stress performance of the vertex member and the deep plastic ratio of the whole structure can serve as qualitative indicators to distinguish different failure modes. 展开更多
关键词 external blast loading Reticulated dome structure Fluid-structure interaction Dynamic response mode Response mechanism
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Influence of external circulation on sludge characteristics during start-up of internal circulation reactor 被引量:4
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作者 丁建南 王淀佐 《Journal of Central South University of Technology》 EI 2005年第4期425-429,共5页
The start-up of external circulationadded internal circulation(IC) reactor was finished in 26 d, 32 d fewer than that of IC reactor. To evaluate the influence of the added external circulation on the development of gr... The start-up of external circulationadded internal circulation(IC) reactor was finished in 26 d, 32 d fewer than that of IC reactor. To evaluate the influence of the added external circulation on the development of granular sludge, the characteristics of the granular sludge taken from the two tested laboratory-scale reactors during start-up were studied. The results show that the added external circulation can enhance biomass granulation, accelerate granule development and improve sludge characteristics. At the end of start-up, the granular size of sludge in external circulation-added IC reactor greatly increases with a size distribution much better than that of sludge in IC reactor. The granular sludge originated from external circulationadded IC reactor contains more extracellular polymers and has a greater settling velocity than that from IC reactor. Methanogenic activity of the granular sludge from the external circulationadded IC reactor started 26 d ago reaches 358.23mL·g -1 ·d -1 , 1.66 and 1.20 times as great as that of the sludge from the IC reactor started 26 d and 58 d ago respectively. 展开更多
关键词 external circulation internal circulation reactor characteristics of granular sludge
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External Influence to Geochemical Assessment of the Land Quality—Atmospheric Dry and Wet Deposition
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作者 Wei Wang,Zhongfang Yang,Qingye Hou,Rongjie Bai School of Earth Sciences and Resources,China University of Geosciences(Beijing),Beijing 100083,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期305-306,共2页
The heavy metals in the atmosphere mainly come from the gas and dust which involved by the energy costs,transport,metallurgy and building materials production.Other than the element of Hg,the heavy metals come into th... The heavy metals in the atmosphere mainly come from the gas and dust which involved by the energy costs,transport,metallurgy and building materials production.Other than the element of Hg,the heavy metals come into the atmosphere in the form of aerosol basically and go into the soil through 展开更多
关键词 GEOCHEMICAL ASSESSMENT atmospheric DEPOSITION DEPOSITION FLUXES external INFLUENCE
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Passive cooling of porous tile used on external wall
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作者 罗庆 刘庆开 夏煦 《Journal of Central South University》 SCIE EI CAS 2009年第S1期135-139,共5页
The porous tiles under the dry and wet conditions were studied. The simplified mathematical model was put forward to simulate the procedure of moisture evaporating for the densely porous tile. The results show that th... The porous tiles under the dry and wet conditions were studied. The simplified mathematical model was put forward to simulate the procedure of moisture evaporating for the densely porous tile. The results show that the capability of passive cooling of the porous tile is more than 5 ℃ with moisture content of 30% in Yangtze river region. Through the comparison between the measuring and simulating data,it can be proved that the simplified math model can be fully used to the engineering application,which provides a reference to explore the thermal performance of other porous material. 展开更多
关键词 POROUS material external WALL PASSIVE COOLING building energy efficiency
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Impact of external carbon source on A2/O system and its biological phosphorus and nitrogen removal efficiency before and after restoration 被引量:4
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作者 LIU Fangjing DUAN Yitong +2 位作者 ZHAO Jianhui CHENG Guoling LI Yongfeng 《环境污染与防治》 CAS CSCD 北大核心 2014年第4期I0004-I0009,10,共6页
以啤酒废水作为外加碳源,研究了不同浓度外加碳源对A2/O系统的冲击情况,并通过调节工艺参数对系统进行修复,对比了修复前后系统的脱氮除磷效果。结果表明,投加低浓度(COD为50mg/L)外加碳源没有影响系统的正常运行,且有助于提... 以啤酒废水作为外加碳源,研究了不同浓度外加碳源对A2/O系统的冲击情况,并通过调节工艺参数对系统进行修复,对比了修复前后系统的脱氮除磷效果。结果表明,投加低浓度(COD为50mg/L)外加碳源没有影响系统的正常运行,且有助于提高系统的脱氮除磷效率;用COD为150mg/L的啤酒废水对系统进行冲击时,总氮、氨氮、总磷和COD的去除率均有所下降,依次下降了31.53、16.38、7.61、10.19百分点;经过修复后,与冲击前相比较,各分析指标的去除率略有降低。用高浓度(COD为250nag/L)的啤酒废水冲击A2/O系统,冲击期间各分析指标显著下降,且产生轻微的污泥膨胀,修复后各分析指标去除率依次降低了11.75、9.56、21.20、20.79百分点。实验表明,啤酒废水可以作为外加碳源用以调节系统的C/N,且A0/o系统对浓度变化的冲击具有一定的抵抗力。 展开更多
关键词 环境污染 环境防治 环境治理 环境保护 大气污染
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Robust H∞ Consensus Control for High-order Discrete-time Multi-agent Systems With Parameter Uncertainties and External Disturbances 被引量:3
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作者 Jun Xu Guoliang Zhang +2 位作者 Jing Zeng Boyang Du Xiao Jia 《自动化学报》 EI CSCD 北大核心 2017年第10期1850-1857,共8页
关键词 参数不确定性 多智能体系统 离散时间 一致性控制 高阶 外部扰动 鲁棒 线性矩阵不等式
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Ab initio study offree radical underthe Si (CH3) 2O doubleexternal electric field
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作者 CHENXiao-jun LUOSun-zhong +4 位作者 JIANGShu-bing HUANGWei GAOXiao-ling MAMei-zhong ZHUZheng-he 《原子与分子物理学报》 CAS CSCD 北大核心 2004年第2期203-209,共7页
Infrared spectrum and NMR chemical shifts of Si (CH3)2O double free radical were calculatedemploying density functional theory(DFT) with the basis sets 6 - 311 + G(2d, p). Excited states, dipole momentand energy of Si... Infrared spectrum and NMR chemical shifts of Si (CH3)2O double free radical were calculatedemploying density functional theory(DFT) with the basis sets 6 - 311 + G(2d, p). Excited states, dipole momentand energy of Si(CH3 )2O double free radical were also calculated using time dependent density function theory(TD-DFT) with the same basis sets. It is found that the external electric field along the X,Y and Z axis affectdifferently on the excited states and other properties of Si(CH3)2O double free radical. 展开更多
关键词 TDDFT Si(CH3)2O EXCITED STATES DIPOLE MOMENT external electric field
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THE PROBLEM OF AN EXTERNAL CIRCULAR CRACK UNDER ASYMMETRIC LOADINGS 被引量:4
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作者 王银邦 《应用数学和力学》 EI CSCD 北大核心 2001年第1期9-15,共7页
Using the boundary integral equation method, the problem of an external circular crack in a three_dimensional infinite elastic body under asymmetric loadings is investigated. The two_dimensional singular boundary inte... Using the boundary integral equation method, the problem of an external circular crack in a three_dimensional infinite elastic body under asymmetric loadings is investigated. The two_dimensional singular boundary integral equations of the problem were reduced to a system of Abel integral equations by means of Fourier series and hypergeometric functions. The exact solutions of stress intensity factors are obtained for the problem of an external circular crack under asymmetric loadings, which are even more universal than the results obtained by the use of Hankel transform method. The results demonstrate that the boundary integral equation method has great potential as a new analytic method. 展开更多
关键词 外部圆形裂纹 非对称载荷 边界积分方程 ABEL方程 应力强度因子
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Discussion on the Subjectivity's Play and Strategies in External-propaganda Translation
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作者 Yu Yiqi 《学术界》 CSSCI 北大核心 2014年第6期266-271,共6页
External-propaganda translation,as a language translation way,aims to influence the relevant audiences and then promote them to change attitude or take certain actions in discourse patterns. English translation,as the... External-propaganda translation,as a language translation way,aims to influence the relevant audiences and then promote them to change attitude or take certain actions in discourse patterns. English translation,as the external- propaganda material of Chinese government,is an important window for the foreign audiences to know well China,while a translator is the subject of translation practice and the key person to realize the function of texts,and also plays a decisive,significant role in the quality of translation. In external-propaganda translation,the strategies for playing the subjectivity of translator mainly include laying an emphasis on the selection of theme,making sure about the object,and paying attention to methods. 展开更多
关键词 语言翻译 中国政府 英文翻译 窗口
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On the Relationship of the Opening Strategy and the Imbalance of the Internal and External Trade in China
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作者 Pan Liang 《学术界》 CSSCI 北大核心 2015年第3期262-266,共5页
The imbalance of the internal and external trade of China has long been a problem; the external imbalance embodies itself as the long- term surplus of the international balance of payment caused by twin surpluses,and ... The imbalance of the internal and external trade of China has long been a problem; the external imbalance embodies itself as the long- term surplus of the international balance of payment caused by twin surpluses,and the internal imbalance is characterized by high investment,low consumption,high saving rate and the periodic inflation. This paper attempts to analyze the role of the opening strategy in the problem of the imbalance. Under the influence of the internal economic,political and social environment,the export- oriented,opening strategy of introduction of foreign capital and stabilization of exchange rate is established,which may increase the risk of inflation. 展开更多
关键词 失衡 中国 贸易 通货膨胀 平衡问题 社会环境 引进外资 不平衡
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网络安全问题研究:逻辑起点、具体表现与治理路径——基于外部性理论视域 被引量:3
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作者 肖军 陈林培 《情报杂志》 北大核心 2025年第1期121-127,共7页
[研究目的]针对目前网络安全所存在的网络安全国际合作失衡、技术“军事化”“武器化”、安全外部依赖等负外部性问题,利用外部性理论解析其产生原因,并进行针对性解决,旨在构建更加系统的网络安全体系。[研究方法]通过文献分析法、案... [研究目的]针对目前网络安全所存在的网络安全国际合作失衡、技术“军事化”“武器化”、安全外部依赖等负外部性问题,利用外部性理论解析其产生原因,并进行针对性解决,旨在构建更加系统的网络安全体系。[研究方法]通过文献分析法、案例研究法,并结合外部性理论,阐释了网络安全外部性产生的根源以及具体表现。[研究结果/结论]主体利益冲突是网络安全外部性产生的直接原因,准国际性、准公共性及技术的外溢性加剧了外部性的产生。可借鉴传统的化解外部性的四种方式并结合网络安全治理实际,从探寻有效的网络安全国际合作与反制机制、平衡网络安全市场与政府的力量投入、重视网络安全人员监督管理与福利措施等途径入手。 展开更多
关键词 外部性理论 负外部性 网络安全 国家安全 利益冲突
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公共性与全民性:习近平生态文明思想的价值指向 被引量:2
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作者 刘科 黄博琛 《河南师范大学学报(哲学社会科学版)》 北大核心 2025年第1期24-30,共7页
公共性与全民性是诠释政府公共行动的学理视角,民众平等的权利地位是理解公共性的前提,政府向民众让渡公共权利是推进善治的基础。在生态治理实践中,各类生态产品具有的社会本质属性使其呈现强大的公共性,能够有效保障社会的健全发展,... 公共性与全民性是诠释政府公共行动的学理视角,民众平等的权利地位是理解公共性的前提,政府向民众让渡公共权利是推进善治的基础。在生态治理实践中,各类生态产品具有的社会本质属性使其呈现强大的公共性,能够有效保障社会的健全发展,满足民众生存与发展的共同需求。生态治理离不开政府部门的主导作用,也需要凝聚全社会尊重自然的思想共识,需要全民自觉的生态行为。习近平生态文明思想立足于生态产品的公共属性,以人民福祉为根本关切,积极回应全民性的生态诉求,具有鲜明的价值指向。充分认识和理解生态文明建设的公共性、全民性和优先性,树立生态文明建设的人民情怀和公共精神,有助于提升民众参与生态治理的获得感、幸福感和安全感,进而全面推进构建人类生态命运共同体,有效化解全球生态危机,实现生态福利、生态正义和生态安全等公共性环境目标。 展开更多
关键词 生态文明治理 公共性 全民性 外部性
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外包钢加固锈蚀箍筋混凝土柱抗剪承载力模型 被引量:1
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作者 李强 曹腾飞 +3 位作者 陈少杰 阎沛霖 汪勇 刘晓岩 《西安科技大学学报》 北大核心 2025年第1期161-169,共9页
为研究锈蚀箍筋混凝土柱外包型钢加固后的抗剪承载能力,设计9根不同箍筋间距的混凝土柱,对其中7根混凝土柱通电加速锈蚀箍筋,采用水泥基灌浆料或环氧树脂胶作为外包型钢加固柱的填充物,加固处理后进行低周往复荷载试验;以箍筋间距、箍... 为研究锈蚀箍筋混凝土柱外包型钢加固后的抗剪承载能力,设计9根不同箍筋间距的混凝土柱,对其中7根混凝土柱通电加速锈蚀箍筋,采用水泥基灌浆料或环氧树脂胶作为外包型钢加固柱的填充物,加固处理后进行低周往复荷载试验;以箍筋间距、箍筋锈蚀率和填充物为变量,综合运用试验研究与理论分析方法对其破坏形态和抗剪承载性能进行分析;基于混凝土柱极限抗剪承载力计算模型,引入外包型钢有效利用系数,建立外包型钢加固锈蚀箍筋混凝土柱斜截面抗剪承载力计算模型。结果表明:在低周往复荷载作用下柱底形成塑性铰、柱底加固型钢连接处失效,箍筋间距和箍筋锈蚀率等因素共同影响其抗剪承载力;相同箍筋间距及锈蚀率下采用水泥基灌浆料与环氧树脂胶对外包型钢与混凝土柱协同工作性能一致;加固后外包型钢对核心区混凝土约束能力的提升,显著提高了混凝土柱的抗剪承载力。研究可为外包型钢加固锈蚀箍筋混凝土柱采用水泥基灌浆料作为填充物提供实践指导,为抗剪承载力计算、耐久性分析提供理论参考。 展开更多
关键词 混凝土柱 箍筋锈蚀 抗剪承载力 外包型钢加固 抗震性能
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体外预应力钢绞线加固钢吊车梁受弯性能试验 被引量:1
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作者 高志刚 苗哲 +3 位作者 何佳晨 张程华 秦卿 张华 《西安科技大学学报》 北大核心 2025年第2期351-361,共11页
为有效解决传统加固钢吊车梁施工工艺复杂、难度高、周期长、成本高等问题,提出体外预应力钢绞线加固钢吊车梁法。共设计制作3根试验梁,加固组钢绞线施加预应力130 kN,通过静力加载试验,对加固梁和未加固梁的破坏形态、荷载-挠度曲线、... 为有效解决传统加固钢吊车梁施工工艺复杂、难度高、周期长、成本高等问题,提出体外预应力钢绞线加固钢吊车梁法。共设计制作3根试验梁,加固组钢绞线施加预应力130 kN,通过静力加载试验,对加固梁和未加固梁的破坏形态、荷载-挠度曲线、梁跨变形规律及上翼缘、腹板、下翼缘的应变分布规律进行分析。结果表明:试件梁的破坏形态均为典型弯曲破坏,直线布线加固梁破坏时钢绞线跨中与梁下翼缘接触,加载点处屈曲;折线布线加固梁钢绞线在跨中断裂破坏,加载点处屈曲,钢梁发生回弹;当许用挠度达到6.75 mm时,未加固梁荷载为63 kN,直线布线加固梁荷载为71 kN,折线布线加固梁荷载为115 kN;直线布线加固钢梁极限承载力提高了29.36%,屈服荷载提高了17.07%,折线布线加固钢梁极限承载力提高了85.32%,屈服荷载提高了107%。研究认为折线布线加固钢梁效果最佳,能够有效提高钢梁承载力,对现有服役期工作的钢吊车梁加固设计有一定参考价值。 展开更多
关键词 钢吊车梁 体外预应力 静力加载试验 变形 应变
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