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论国民经济协调系数体系的建立 被引量:36
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作者 王维国 《统计研究》 CSSCI 北大核心 1995年第4期66-68,共3页
论国民经济协调系数体系的建立王维国协调发展既是国民经济发展过程中的一种客观要求,又是国民经济健康、持续、快速发展的前提。只有了解国民经济协调发展状况,才能制定出国民经济健康、持续、快速发展的战略。因此,准确评估国民经... 论国民经济协调系数体系的建立王维国协调发展既是国民经济发展过程中的一种客观要求,又是国民经济健康、持续、快速发展的前提。只有了解国民经济协调发展状况,才能制定出国民经济健康、持续、快速发展的战略。因此,准确评估国民经济协调发展状况意义重大。本文应用模... 展开更多
关键词 国民经济 协调系数体系 协调发展
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相关系数体系探讨 被引量:1
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作者 傅德印 《财经问题研究》 CSSCI 北大核心 1994年第1期62-64,共3页
相关系数体系探讨傅德印一、相关系数体系构造及其意义(一)相关系数体系构造相关系数是用来测定变量间相关关系程度及方向的统计指标。计算相关系数是相关分析的基础内客。纵观相关分析,不难发现,相关系数的计算因资料性质、变量类... 相关系数体系探讨傅德印一、相关系数体系构造及其意义(一)相关系数体系构造相关系数是用来测定变量间相关关系程度及方向的统计指标。计算相关系数是相关分析的基础内客。纵观相关分析,不难发现,相关系数的计算因资料性质、变量类型及变量多少的影响,在方法研究上,... 展开更多
关键词 相关系数体系 相关分析 统计指标
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基于联系数的电子装备体系效能倍增效应分析
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作者 夏斌 徐勇 +1 位作者 柯宏发 贺齐辉 《火力与指挥控制》 CSCD 北大核心 2016年第2期72-76,81,共6页
提出了基于联系数的电子装备系统和体系作战效能倍增效应分析新方法。首先介绍了联系数的定义与数学运算,其次提出以基于作战能力指数的同异联系数来描述电子装备的作战效能,并根据不确定系数的取值分别对电子装备系统和体系的作战效能... 提出了基于联系数的电子装备系统和体系作战效能倍增效应分析新方法。首先介绍了联系数的定义与数学运算,其次提出以基于作战能力指数的同异联系数来描述电子装备的作战效能,并根据不确定系数的取值分别对电子装备系统和体系的作战效能倍增效应进行了分析,最后基于侦察装备对目标的侦察能力进行了实例分析,结果表明该方法合理可行。 展开更多
关键词 系统工程方法论 作战效能 倍增效应 系数 电子装备体系
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基于贝叶斯网络的结构易损性智能推理
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作者 方圣恩 俞其康 +1 位作者 张笑华 林友勤 《自然灾害学报》 CSCD 北大核心 2024年第3期130-136,共7页
为实现结构易损性的智能化推理,提出以贝叶斯网络(Bayesian networks,BNs)重构桁架结构的易损性分析体系。首先,分别定义外荷载、体系和杆件为网络顶层父节点、中间节点和底层子节点,节点间通过有向弧表示因果关系,形成BN拓扑;接着,提... 为实现结构易损性的智能化推理,提出以贝叶斯网络(Bayesian networks,BNs)重构桁架结构的易损性分析体系。首先,分别定义外荷载、体系和杆件为网络顶层父节点、中间节点和底层子节点,节点间通过有向弧表示因果关系,形成BN拓扑;接着,提出以杆件“大损伤”替代传统的“概念移除”方式,考虑杆件参数及外荷载的不确定性,结合抽样实现对节点间条件概率表的学习,完成BN的构建;然后将特定杆件的观测状态作为证据输入BN,同步推理其他杆件的节点状态概率,进而计算杆件的重要性系数,并定义所有杆件的重要性系数之和为体系的易损性系数;最后,提出杆件易损指标,作为预测桁架体系最可能失效路径的依据。研究结果表明:所提方法能更合理地评价各杆件在体系中的重要性,推理得到的杆件破坏路径与试验观测一致,所计算的试验桁架体系易损性系数远小于杆件数目,表明当前荷载组合下特定杆件的损伤引起体系发生连续性倒塌的可能性较小。 展开更多
关键词 结构工程 贝叶斯网络 杆件重要性系数 体系易损性系数 杆件易损指标
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照明设计中利用系数的形成
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作者 高峰 《黑龙江科技信息》 2003年第8期82-82,共1页
关键词 照明设计 利用系数 英国球带法 分布系数体系
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FREE VIBRATION ANALYSIS OF SHEAR WALLS WITH SHORT PIERS 被引量:1
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作者 黄东升 刘世美 +2 位作者 华新钰 刘俊龙 艾军 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第3期194-201,共8页
The equations of the lateral deflection curve of the short pier shear wall under a lateral concentrated load at any level are derived by employing a continuous approach. Lateral flexibility matrixes for the dynamic an... The equations of the lateral deflection curve of the short pier shear wall under a lateral concentrated load at any level are derived by employing a continuous approach. Lateral flexibility matrixes for the dynamic analysis are also obtained by repeatedly calculating the lateral unit load on the wall at each level where a lumped mass located. Dynamic analyses are implemented for short pier shear walls with different parameters, called the integrative coefficient and the pier strength coefficient related to the dimensions of walls. The influences of two coefficients on the dynamic performances of the structure are studied. Results indicate that with the increase of the integrative coefficient, the periods of top two modes apparently decrease but the other periods of higher frequency modes show little variation when the pier strength coefficient remains constant. Similarly, if the integrative coefficient is constant, the top two periods of the free vibration decrease with the increase of the integrative coefficient but the other periods of higher frequency modes show less variation. 展开更多
关键词 shear wall with short piers dynamic analysis integrative coefficient pier strength coefficient
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夏热冬冷地区居住建筑节能设计初探 被引量:3
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作者 姚大江 邱文航 《华中建筑》 2006年第4期205-208,共4页
能源供应日益紧张、社会对绿色环保节能建筑的呼声不断高涨。由于目前可供选择的节能保温材料不多,能采用的保温节能方式有限,所以该领域的发展前景还十分广阔。现在国家倡导产品自主创新,如果材料、科研与设计能携手合作,该领域必将大... 能源供应日益紧张、社会对绿色环保节能建筑的呼声不断高涨。由于目前可供选择的节能保温材料不多,能采用的保温节能方式有限,所以该领域的发展前景还十分广阔。现在国家倡导产品自主创新,如果材料、科研与设计能携手合作,该领域必将大有可为。 展开更多
关键词 节能建筑 采暖空调年耗电量 规范限值 体系系数 窗墙比 外墙平均传热系教
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Electrochemical behavior of Pb(Ⅱ) in LiCl-KCl-MgCl_2-PbCl_2 melts on Mo electrode 被引量:4
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作者 张密林 陈丽军 +2 位作者 韩伟 颜永得 曹鹏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第3期711-716,共6页
Cyclic voltammetry and chronopotentiometry were used to study the reaction mechanism of Pb(Ⅱ) and the co-deposition of Pb,Mg and Li on molybdenum electrodes in LiCl-KCl-PbCl2-MgCl2 melts.The diffusion coefficient o... Cyclic voltammetry and chronopotentiometry were used to study the reaction mechanism of Pb(Ⅱ) and the co-deposition of Pb,Mg and Li on molybdenum electrodes in LiCl-KCl-PbCl2-MgCl2 melts.The diffusion coefficient of lead ions in the melts was determined by different electrochemical techniques.The results obtained by cyclic voltammetry and chronopotentiometry indicated that the underpotential deposition of lithium on pre-deposited Pb leads to the formation of a liquid Li-Pb alloy,and the Mg-Li-Pb alloys are formed after the addition of MgCl2.X-ray diffraction confirmed that in the Mg-Li-Pb alloy,PbLi3,Mg2Pb and Li7Pb2 phases exist by galvanostatic electrolysis at 6.21 A/cm2 for 2 h at 873 K and the phases can be controlled by changing the concentration of PbCl2 and MgCl2. 展开更多
关键词 LiCl-KCl system cyclic voltammetry CHRONOPOTENTIOMETRY diffusion coefficient molten salts electrolysis
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侧向刚度不规则对框架结构抗震能力影响的评估
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作者 刘培 黄世敏 程绍革 《地震工程与工程振动》 CSCD 北大核心 2014年第S1期372-378,共7页
本文从楼层屈服强度系数ξy的角度分析了3个框架结构模型振动台试验,得出可以利用综合抗震能力指数β来评判不同地震强度下框架结构的破坏状态。对于刚度沿竖向不规则的框架结构,在处于基本完好状态时,侧向刚度不规则对β的影响可忽略不... 本文从楼层屈服强度系数ξy的角度分析了3个框架结构模型振动台试验,得出可以利用综合抗震能力指数β来评判不同地震强度下框架结构的破坏状态。对于刚度沿竖向不规则的框架结构,在处于基本完好状态时,侧向刚度不规则对β的影响可忽略不计;但在处于严重破坏状态时,侧向刚度不规则对β的影响不可忽略。本文还设计了8个仅底层层高变化的算例,根据结构侧向刚度不规则的程度,将体系影响系数ψ1的取值进一步细化。 展开更多
关键词 抗震鉴定 钢筋混凝土框架结构 楼层屈服强度系数 楼层综合抗震能力指数 侧向刚度 体系影响系数
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对门式钢架风荷载不利作用的分析研究
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作者 闫亚汐 杜秉旋 +1 位作者 栾力文 刘君阳 《四川水泥》 2015年第11期44-,共1页
本文主要根据MBMA《低层房屋体系手册》中有关小坡度房屋的规定针对门式钢架风荷载计算过程中的几种不利情况进行了分析比对。分析得出当端区宽度大于二分之一柱距且小于柱距时,第二榀刚架最容易出现风荷载计算的错误。因此在设计第二... 本文主要根据MBMA《低层房屋体系手册》中有关小坡度房屋的规定针对门式钢架风荷载计算过程中的几种不利情况进行了分析比对。分析得出当端区宽度大于二分之一柱距且小于柱距时,第二榀刚架最容易出现风荷载计算的错误。因此在设计第二榀刚架时,应反复核对端区宽度,最终确定风荷载体系系数。 展开更多
关键词 门式刚架 风荷载 不利作用 体系系数
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危险货物办理站安全质量评估方法初探 被引量:4
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作者 吴育俭 徐静华 《中国安全科学学报》 CAS CSCD 1995年第S2期89-92,63,共5页
从铁路危险货物的运输现状出发,通过对影响危险货物办理站安全工作质量的因素的分析,探讨了安全质量的评估方法,并提出了一个新的概念──安全管理难度系数,由此建立起安全质量综合评估模型,以实现对危险货物办理站安全工作的全面... 从铁路危险货物的运输现状出发,通过对影响危险货物办理站安全工作质量的因素的分析,探讨了安全质量的评估方法,并提出了一个新的概念──安全管理难度系数,由此建立起安全质量综合评估模型,以实现对危险货物办理站安全工作的全面衡量。 展开更多
关键词 危险货物办理站 安全质量评估 安全质量指标评估体系 安全管理难度系数 安全质量 综合评估模型
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路基回弹模量对路面结构层受力的影响分析 被引量:5
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作者 刘大鹏 王婧 《路基工程》 北大核心 2008年第1期123-124,共2页
通过计算不同路基回弹模量下的弯沉系数、上层底面弯拉应力系数、中层底面弯拉应力系数以及三层体系表面最大剪应力系数,得出了这些系数和路基回弹模量的关系。
关键词 路基回弹模量 弯沉系数 上、中层底面弯拉应力系数 三层体系表面最大剪应力系数
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Relevance of zero lift drag coefficient and lift coefficient to Mach number for large aspect ratio winged rigid body
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作者 董素荣 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第3期270-274,共5页
Synthetic analysis is conducted to the wind tunnel experiment results of zero lift drag coefficient and lift coefficient for large aspect ratio winged rigid body.By means of wind tunnel experiment data,the dynamics mo... Synthetic analysis is conducted to the wind tunnel experiment results of zero lift drag coefficient and lift coefficient for large aspect ratio winged rigid body.By means of wind tunnel experiment data,the dynamics model of the zero lift drag coefficient and lift coefficient for the large aspect ratio winged rigid body is amended.The research indicates that the change trends of zero lift drag coefficient and lift coefficient to Mach number are similar.The calculation result and wind tunnel experiment data all verify the validity of the amended dynamics model by which to estimate the zero lift drag coefficient and lift coefficient for the large aspect ratio winged rigid body,and thus providing some technical reference to aerodynamics character analysis of the same types of winged rigid body. 展开更多
关键词 winged rigid body zero lift drag coefficient lift coefficient wind tunnel experiment dynamic characteristics
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Hydrodynamic Behavior of a Single Bubble Rising in Viscous Liquids 被引量:7
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作者 CAI Ziqi BAO Yuyun GAO Zhengming 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第6期923-930,共8页
The rising behavior of single bubbles has been investigated in six systems with different viscosity and Morton number(Mo) from 3.21×10-11 to 163. Bubbles with maximum equivalent diameter of up to 16 mm were inves... The rising behavior of single bubbles has been investigated in six systems with different viscosity and Morton number(Mo) from 3.21×10-11 to 163. Bubbles with maximum equivalent diameter of up to 16 mm were investigated. The bubble Reynolds number(Re) ranged from 0.02 to 1200 covering 3 regimes in which two func-tions are obtained relating the drag coefficient,CD,with Re and Mo. It has been found that in the high Reynolds number regime the drag coefficient increases until the Reynolds number of about 1200. The classic expression of Jamialahmadi(1994) is improved and extended to high viscosity liquids. A new relationship for the aspect ratio of deformed bubbles in terms of Re,the Etvs number and Mo,applicable to a wide range of system properties,espe-cially in high viscosity liquids,is also suggested. 展开更多
关键词 BUBBLE rising velocity viscous liquid drag coefficient DEFORMATION
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Measurement and Correlation of Partition Coefficients of Baicalin in EOPO/Salt Aqueous Two-Phase Systems 被引量:1
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作者 李伟 朱自强 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第6期666-669,共4页
The partition coefficients of baicalin were measured in ethylene oxide and propylene oxide (EOPO)/salt aqueous two-phase systems at 298.15K. It was found that most of baicalin partitioned into EOPO-rich phase. The par... The partition coefficients of baicalin were measured in ethylene oxide and propylene oxide (EOPO)/salt aqueous two-phase systems at 298.15K. It was found that most of baicalin partitioned into EOPO-rich phase. The partition coefficients of baicalin varied from 10 to 120. The effect of various factors, including tie-line length, salt composition, molecular weight of EOPO, and solution pH, on the partition behavior was investigated in EOPO/salt systems. Furthermore the partition coefficients of baicalin were correlated using the modified Diamond-Hsu model. Good agreement with experimental data is obtained. The average relative deviations are less than 5.0%. 展开更多
关键词 aqueous two-phase system ethylene oxide and proplene oxide partition coefficient BAICALIN
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STUDY ON THE FRAMEWORK SYSTEM OF DIGITAL AGRICULTURE 被引量:9
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作者 LIANGYong LUXiu-shan +2 位作者 ZHANGDe-gui LIANGFu RENZhi-bo 《Chinese Geographical Science》 SCIE CSCD 2003年第1期15-19,共5页
China is a great agricultural country with large population, limited soilresources and traditional farming mode, so the central government has been attaching greatimportance to the development of agriculture and put f... China is a great agricultural country with large population, limited soilresources and traditional farming mode, so the central government has been attaching greatimportance to the development of agriculture and put forward a new agricultural technologyrevolution ― the transformation from traditional agriculture to modern agriculture and fromextensive farming to intensive farming. Digital agriculture is the core of agriculturalinformatization. The enforcement of digital agriculture will greatly promote agricultural technologyrevolution, two agricultural transformations and its rapid development, and enhance China'scompetitive power after the entrance of WTO. To carry out digital agriculture, the frame system ofdigital agriculture is required to be studied in the first place. In accordance with the theory andtechnology of digital earth and in combination with the agricultural reality of China, this articleoutlines the frame system of digital agriculture and its main content arid technology support. 展开更多
关键词 digital agriculture framework system 3S technology spatial data
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Mass transfer characteristics in a rotating packed bed with split packing 被引量:4
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作者 Youzhi Liu Deyin Gu +2 位作者 Chengcheng Xu Guisheng Qi Weizhou Jiao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第5期868-872,共5页
The rotating packed bed (RPB) with split packing is a novel gas-liquid contactor, which intensifies the mass transfer processes controlled by gas-side resistance. To assess its efficacy, the mass transfer characteri... The rotating packed bed (RPB) with split packing is a novel gas-liquid contactor, which intensifies the mass transfer processes controlled by gas-side resistance. To assess its efficacy, the mass transfer characteristics with adjacent rings in counter-rotation and co-rotation modes in a split packing RPB were studied experimentally. The physical absorption system NH3-H2O was used for characterizing the gas volumetric mass transfer coeffi- cient (kyae) and the effective inteffacial area (ae) was determined by chemical absorption in the CO2-NaOH sys- tem. The variation in kyae and ae with the operating conditions is also investigated. The experimental results indicated that kyae and ae for counter-rotation of the adjacent packing rings in the split packing RPB were higher than those for co-rotation, and both counter-rotation and co-rotation of the split packing RPB were superior over conventional RPBs under the similar ooerating conditions. 展开更多
关键词 Rotating packed bed (RPB) Split packing Mass transfer Physical absorption Chemical absorption
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New Change of Technical Indicators System of Watt-Hour Meters
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作者 盛泉根 《China Standardization》 2012年第3期68-71,共4页
There is an imperfection in the accuracy indicators system and the technical parameters system in IEC standards 62053-21 implemented for watt-hour meters currently. This article quoted some parts of OIML MI-003 and R4... There is an imperfection in the accuracy indicators system and the technical parameters system in IEC standards 62053-21 implemented for watt-hour meters currently. This article quoted some parts of OIML MI-003 and R46 contents to provide a reference of the integrity comparison between the accuracy system and technical parameter system. The comparison result shows that the watt-hour meter accuracy technical indicators system of OIML R46 is more integrated. First reason is that it determines all the accuracy (basic error) defining rules just by using the technical parameter I efficiently; secondly, it can solve the contradiction that no error regulation of the range from starting current to minimum current in the process of providing, handing over and checking watt-hour meter products' qualities efficiently. Please pay close attention to the R46 official version which will be released soon, as it is still in the Committee Draft (CD6) stage currently. 展开更多
关键词 OIML R46 technical indicator ACCURACY watt-hour meter
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Form Invariance of Raitzin's Canonical Equations of Relativistic Mechanical System
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作者 ZHAOShu-Hong SUNFu-Tian QIAOYong-Fen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4期607-610,共4页
A form invariance of Raitzin's canonical equations of relativistie mechanical system is studied. First, the Raitzin's canonical equations of the system are established. Next, the definition and criterion of th... A form invariance of Raitzin's canonical equations of relativistie mechanical system is studied. First, the Raitzin's canonical equations of the system are established. Next, the definition and criterion of the form invariance in the system under infinitesimal transformations of groups are given. Finally,the relation between the form invariance and the conserved quantity of the system is obtained and an example is given to illustrate the application of the result. 展开更多
关键词 form in variance conserved quantity Raitzin's canonical equation relativistic holonomic system
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Calculation of Transport Properties of CF4+Noble Gas Mixtures 被引量:2
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作者 Soodabeh Nikmanesh Jalil Moghadasi Mohammad Mehdi Papari 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第5期814-821,共8页
The present work is concerned with determining the viscosity,diffusion,thermal diffusion factor and thermal conductivity of five equimolar binary gas mixtures including:CF4-He,CF4-Ne,CF4-Ar,CF4-Kr,CF4-Xe from the prin... The present work is concerned with determining the viscosity,diffusion,thermal diffusion factor and thermal conductivity of five equimolar binary gas mixtures including:CF4-He,CF4-Ne,CF4-Ar,CF4-Kr,CF4-Xe from the principle of corresponding states of viscosity by the inversion technique.The Lennard-Jones (12-6) model potential is used as the initial model potential.The calculated interaction potential energies obtained from the inversion procedure is employed to reproduce the viscosities,diffusions,thermal diffusion factors,and thermal conductivities.The accuracies of the calculated viscosity and diffusion coefficients were 1% and 4%,respectively. 展开更多
关键词 corresponding states principle DIFFUSION inversion method kinetic theory of gases thermal conductivity transport properties VISCOSITY
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