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Modeling compatible single-tree aboveground biomass equations for masson pine(Pinus massoniana) in southern China 被引量:21
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作者 ZENG Wei-sheng TANG Shou-zheng 《Journal of Forestry Research》 CAS CSCD 2012年第4期593-598,共6页
Because of global climate change, it is necessary to add forest biomass estimation to national forest resource monitoring. The biomass equations developed for forest biomass estimation should be compatible with volume... Because of global climate change, it is necessary to add forest biomass estimation to national forest resource monitoring. The biomass equations developed for forest biomass estimation should be compatible with volume equations. Based on the tree volume and aboveground biomass data of Masson pine (Pinus massoniana Lamb.) in southern China, we constructed one-, two- and three-variable aboveground biomass equations and biomass conversion functions compatible with tree volume equations by using error-in-variable simultaneous equations. The prediction precision of aboveground biomass estimates from one variable equa- tion exceeded 95%. The regressions of aboveground biomass equations were improved slightly when tree height and crown width were used together with diameter on breast height, although the contributions to regressions were statistically insignificant. For the biomass conversion function on one variable, the conversion factor decreased with increasing diameter, but for the conversion function on two variables, the conversion factor increased with increasing diameter but decreased with in- creasing tree height. 展开更多
关键词 aboveground biomass error-in-variable simultaneous equa- tions mean prediction error compatibility Pinus massoniana
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CloudRank-D: benchmarking and ranking cloud computing systems for data processing applications 被引量:5
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作者 Chunjie LUO Jianfeng ZHAN +5 位作者 Zhen JIA Lei WANG Gang LU Lixin ZHANG Cheng-Zhong XU Ninghui SUN 《Frontiers of Computer Science》 SCIE EI CSCD 2012年第4期347-362,共16页
With the explosive growth of information, more and more organizations are deploying private cloud systems or renting public cloud systems to process big data. However, there is no existing benchmark suite for evaluati... With the explosive growth of information, more and more organizations are deploying private cloud systems or renting public cloud systems to process big data. However, there is no existing benchmark suite for evaluating cloud performance on the whole system level. To the best of our knowledge, this paper proposes the first benchmark suite CloudRank-D to benchmark and rank cloud computing sys- tems that are shared for running big data applications. We an- alyze the limitations of previous metrics, e.g., floating point operations, for evaluating a cloud computing system, and propose two simple metrics: data processed per second and data processed per Joule as two complementary metrics for evaluating cloud computing systems. We detail the design of CloudRank-D that considers representative applications, di- versity of data characteristics, and dynamic behaviors of both applications and system software platforms. Through experi- ments, we demonstrate the advantages of our proposed met- tics. In several case studies, we evaluate two small-scale de- ployments of cloud computing systems using CloudRank-D. 展开更多
关键词 data center systems CLOUDS big data applica- tions benchmarks evaluation metrics
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Influence of environmental factors on corrosion damage of aircraft structure 被引量:4
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作者 Keliang Ren,) Shiwu Gao, Pingping Liu, and Yan Dong Department of Physics & Electrical Information, Ningxia University, Ningxia 750021, China 《Theoretical & Applied Mechanics Letters》 CAS 2011年第6期18-21,共4页
Corrosion is one of the important structural integrity concerns of aging aircraft, and it is estimated that a significant portion of airframe maintenance budgets is directed towards corrosion-related problems for both... Corrosion is one of the important structural integrity concerns of aging aircraft, and it is estimated that a significant portion of airframe maintenance budgets is directed towards corrosion-related problems for both military and commercial aircraft. In order to better understand how environmental factors influence the corrosion damage initiation and propagation on aircraft structure and to predict pre-corrosion test pieces of fatigue life and structural integrity of an effective approach, this paper uses the cellular automaton (CA) method to character the effect of electrolyte concentrations, dissolution probabilities, and temperature on the corrosion damage of a metal structure exposed to an aggressive environment, and the procedure for applying the local rules between the cells of the CA to simulate the corrosion damage evolution is formulated. The simulation results show that the different electrolyte concentrations, dissolution probabilities and temperature, the laws of the dissolution current with time are investigated and they obey the time power function. 展开更多
关键词 aircraft structure corrosion damage environmental factors cellular automaton simula- tions
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安徽省2002~2004年“中国结核病控制-日本援助项目”实施情况分析 被引量:5
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作者 刘洁 阚晓宏 《疾病控制杂志》 2006年第1期36-38,共3页
目的分析安徽省实施“项目”3年结核病控制效果。方法根据2002~2004年各实施“项目”县(医)的结核病控制工作季报表及年报表,分析项目支施效果。结果项口实施3年,人口覆盖率由2002年的24.14%提高到2004年的79.82%。活动性病人... 目的分析安徽省实施“项目”3年结核病控制效果。方法根据2002~2004年各实施“项目”县(医)的结核病控制工作季报表及年报表,分析项目支施效果。结果项口实施3年,人口覆盖率由2002年的24.14%提高到2004年的79.82%。活动性病人登记率、新发涂阳病人登记率分别由2002年的41.61/10万、7.32/10万提高到2004年的63.88/10万、19.51/10万。新发涂阳病例中15~54岁年龄段占62.05%。治愈率由2002年的68.99%提高到2004年的78.82t%。结论实施“项目”3年,结核病控制工作成效显著,为加速安徽省结核病控制提供了可靠的依据。 展开更多
关键词 结核 综合预防
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STRONG PREDICTOR-CORRECTOR APPROXIMATION FOR STOCHASTIC DELAY DIFFERENTIAL EQUATIONS 被引量:3
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作者 Yuanling Niu Chengjian Zhang Kevin Burrage 《Journal of Computational Mathematics》 SCIE CSCD 2015年第6期587-605,共19页
This paper presents a strong predictor-corrector method for the numerical solution of stochastic delay differential equations (SDDEs) of ItS-type. The method is proved to be mean-square convergent of order min{1/2,p... This paper presents a strong predictor-corrector method for the numerical solution of stochastic delay differential equations (SDDEs) of ItS-type. The method is proved to be mean-square convergent of order min{1/2,p} under the Lipschitz condition and the linear growth condition, where p is the exponent of HSlder condition of the initial function. Stability criteria for this type of method are derived. It is shown that for certain choices of the flexible parameter p the derived method can have a better stability property than more commonly used numerical methods. That is, for some p, the asymptotic MS-stability bound of the method will be much larger than that of the Euler-Maruyama method. Numerical results are reported confirming convergence properties and comparing stability properties of methods with different parameters p. Finally, the vectorised simulation is discussed and it is shown that this implementation is much more efficient. 展开更多
关键词 Strong predictor-corrector approximation Stochastic delay differential equa- tions CONVERGENCE Mean-square stability Numerical experiments Vectorised simulation.
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循证护理对妇科重症监护患者并发症的影响 被引量:2
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作者 汪文燕 《实用临床医药杂志》 CAS 2015年第22期91-93,共3页
目的探讨循证护理在减少妇科重症监护患者并发症中的应用效果。方法将60例妇科重症监护患者随机分为观察组和对照组,对照组采用常规护理,观察组在对照组的基础上实施循证护理,比较2组患者的并发症、生命体征、住院时间、焦虑情况以及护... 目的探讨循证护理在减少妇科重症监护患者并发症中的应用效果。方法将60例妇科重症监护患者随机分为观察组和对照组,对照组采用常规护理,观察组在对照组的基础上实施循证护理,比较2组患者的并发症、生命体征、住院时间、焦虑情况以及护理满意度。结果观察组护理后的SOFA、APACHEⅡ评分低于对照组,GCS评分高于对照组,差异有统计学意义(P<0.05)。观察组的并发症少于对照组,焦虑评分低于对照组,入住ICU、住院时间短于对照组,护理满意度高于对照组,差异有统计学意义(P<0.05)。结论循证护理有利于减少妇科重症监护患者的并发症,可改善预后,缩短住院时间。 展开更多
关键词 循证护理 妇科 重症监护 并发症 预后
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PALAEOMAGNETIC AND STRUCTURAL INVESTIGATIONS ON BLOCK ROTATIONS AND CRUSTAL SHORTENING IN CENTRAL TIBET
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作者 M. Staiger 1,2 , E. Appel 1, L. Ratschbacher 2, M. Edwards 2 , Bi Siwen 3 2 Tec 《地学前缘》 EI CAS CSCD 2000年第S1期168-169,共2页
As a part of INDEPTH 3/GEODEPTH geological surface investigations were carried out during two field campaigns in 1998 and 1999. The working area covers a roughly N\|S (30~36°N) tren ding, 200km wide belt through... As a part of INDEPTH 3/GEODEPTH geological surface investigations were carried out during two field campaigns in 1998 and 1999. The working area covers a roughly N\|S (30~36°N) tren ding, 200km wide belt through the Lhasa Terrane and Qiangtang Terrane at a longitude of 88~90°E. Field geology was focused on geological mapping, structural measurements, and extensive sampling for the purpose of fission track geochronology. Additionally a total number of 742 orientated palaeomagnetic samples were drilled at 73 sites. Most of the samples were taken in fine\|grained sediments of Cretaceous, Eocene, and Neogene age. Five sites were drilled in acid to intermediate volcanics.A first sequence of measurements has been applied on a set of specimen. Most of the chosen formations (>80%) have acquired stable remanences which are carried by hematite and magnetite. As an example for the characteristic demagnetising behaviour of fine\|grained probable Cretaceous sandstones see Fig.1a. The unblocking temperature of 650℃ allows to identify hematite as remanence carrier.. Although single sites show well\|defined mean directions (e.g. site 76B: α 95 =3 8; k =185 8) the distribution among several site means of one formation could scatter (Fig.1b). It has to be checked carefully if rotations of single crustal elements are responsible for this effect. There is evidence to assume the detected characteristic remanences to be primary—further analysis including fold tests will be performed after the data set has increased. 展开更多
关键词 PALEOMAGNETISM TECTONICS CRUSTAL SHORTENING block rota tions CENTRAL TIBET
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Geoeffectiveness of the coronal mass ejections associated with solar proton events
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作者 Gui-Ming Le Chuan Li +6 位作者 Yu-Hua Tang Liu-Guan Ding Zhi-Qiang Yin Yu-Lin Chen Yang-Ping Lu Min-Hao Chen Zhong-Yi Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第1期117-128,共12页
The intensity-time profiles of solar proton events(SPEs) are grouped into three types in the present study. The Type-I means that the intensity-time profile of an SPE has one peak, which occurs shortly after the ass... The intensity-time profiles of solar proton events(SPEs) are grouped into three types in the present study. The Type-I means that the intensity-time profile of an SPE has one peak, which occurs shortly after the associated solar flare and coronal mass ejection(CME). The Type-II means that the SPE profile has two peaks: the first peak occurs shortly after the solar eruption, the second peak occurs at the time when the CME-driven shock reaches the Earth, and the intensity of the second peak is lower than the first one.If the intensity of the second peak is higher than the first one, or the SPE intensity increases continuously until the CME-driven shock reaches the Earth, this kind of intensity-time profile is defined as Type-III. It is found that most CMEs associated with Type-I SPEs have no geoeffectiveness and only a small part of CMEs associated with Type-I SPEs can produce minor(–50 n T ≤ Dst ≤–30 n T) or moderate geomagnetic storms(–100 n T≤ Dst ≤–50 n T), but never an intense geomagnetic storm(–200 n T ≤ Dst 〈-100 n T). However,most of the CMEs associated with Type-II and Type-III SPEs can produce intense or great geomagnetic storms(Dst ≤-200 n T). The solar wind structures responsible for the geomagnetic storms associated with SPEs with different intensity-time profiles have also been investigated and discussed. 展开更多
关键词 Sun: coronal mass ejections (CMEs) -- Sun: particle emission -- Sun: solar-terrestrial rela- tions
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EVANS FUNCTIONS AND INSTABILITY OF A STANDING PULSE SOLUTION OF A NONLINEAR SYSTEM OF REACTION DIFFUSION EQUATIONS
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作者 Linghai Zhang 《Annals of Applied Mathematics》 2016年第1期79-101,共23页
In this paper, we consider a nonlinear system of reaction diffusion equa- tions arising from mathematical neuroscience and two nonlinear scalar reaction diffusion equations under some assumptions on their coefficients... In this paper, we consider a nonlinear system of reaction diffusion equa- tions arising from mathematical neuroscience and two nonlinear scalar reaction diffusion equations under some assumptions on their coefficients. The main purpose is to couple together linearized stability criterion (the equivalence of the nonlinear stability, the linear stability and the spectral sta- bility of the standing pulse solutions) and Evans functions to accomplish the existence and instability of standing pulse solutions of the nonlinear system of reaction diffusion equations and the nonlinear scalar reaction diffusion equa- tions. The Evans functions for the standing pulse solutions are constructed explicitly. 展开更多
关键词 nonlinear system of reaction diffusion equations standing pulse solutions existence INSTABILITY linearized stability criterion Evans func- tions
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Jordan Triple Derivations on J-subspace Lattice Algebras
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作者 Xiao Fei QI Jin Chuan HOU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2012年第2期417-424,共8页
Let L be a J-subspace lattice on a Banach space X and Alg/2 the associated J-subspace lattice
关键词 J-subspace lattice algebra Jordan triple derivations generalized Jordan triple deriva- tions generalized Jordan derivations
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A New Vector Markov Process for M/G/1 Queue
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作者 严庆强 史定华 郭兴国 《Journal of Shanghai University(English Edition)》 CAS 2005年第2期120-123,共4页
In this paper, by considering the stochastic proces s of the busy period and the idle period, and introducing the unfinished work as a supplementary variable, a new vector Markov process was presented to study th e M... In this paper, by considering the stochastic proces s of the busy period and the idle period, and introducing the unfinished work as a supplementary variable, a new vector Markov process was presented to study th e M/G/1 queue again. Through establishing and solving the density evolution equa tions, the busy-period distribution, and the stationary distributions of waitin g time and queue length were obtained. In addition, the stability condition of th is queue system was given by means of an imbedded renewal process. 展开更多
关键词 M/G/1 queue unfinished work vector Markov process(VMP) density evolution equa tions.
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Modified conceptual model for predicting the tendency of alluvial channel adjustment induced by human activities 被引量:1
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作者 XU JiongxinInstitute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China (e-mail: xujxin?mx.cei.gov.cn) 《Chinese Science Bulletin》 SCIE EI CAS 2001年第S1期51-57,共7页
After a discussion about some limitations of Schumm’s conceptual model for prediction of river metamorphosis, this study introduces the channel boundary material as an independent variable, and thereby establishes a ... After a discussion about some limitations of Schumm’s conceptual model for prediction of river metamorphosis, this study introduces the channel boundary material as an independent variable, and thereby establishes a conceptual model that can be used to predict the direction of channel adjustment induced by human activities. This model has been tested by data from natural rivers and a laboratory model river, and can be used to explain the complex behavior of channel adjustment after reservoir construction. 展开更多
关键词 human influence on CHANNELS CHANNEL BOUNDARY condi- tions feedback in CHANNEL system prediction of CHANNEL adjustment.
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我国石化工业绿色转型的讨论 被引量:1
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作者 夏献民 《安全、健康和环境》 2013年第11期1-2,14,共3页
从资源、环境和竞争力等方面指出我国石化工业面临着绿色转型的必要性和紧迫性,从树立绿色低碳发展理念、研发应用绿色低碳技术、优化工艺和产品结构等方面提出了加快推进绿色转型的措施建议。
关键词 环境保护 低碳发展 节能减排 绿色转型
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ON CHARACTERIZATIONS OF D-η-PROPERLY PREQUASI-INVEX FUNCTION
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作者 Huixian WU Hezhi LUO 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2007年第4期614-622,共9页
Recently, various concepts of D-η-properly prequasi-invex functions were introduced and characterizations of D-η-properly prequasi-invex functions were presented under a certain set of conditions. In this paper, we ... Recently, various concepts of D-η-properly prequasi-invex functions were introduced and characterizations of D-η-properly prequasi-invex functions were presented under a certain set of conditions. In this paper, we show that the same results can be obtained under weaker assumptions. 展开更多
关键词 D-η-properly prequasi-invex functions tions D-η-properly strictly prequasi-invex functions D-η-properly semistrictly prequasi-invex func- upper D-semicontinuity
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预不变拟凸函数的注记(英文)
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作者 彭再云 陈果 《三峡大学学报(自然科学版)》 CAS 2007年第1期70-72,共3页
考虑了由杨新民、杨晓琪教授和Teo在文献[5]中引入的两类新的广义凸函数:预不变拟凸函数和半严格预不变拟凸函数,并得到了它们的3个性质.这些性质包括一定条件下判别半严格预不变拟凸函数的一个新的充分条件以及复合函数的预不变拟凸性... 考虑了由杨新民、杨晓琪教授和Teo在文献[5]中引入的两类新的广义凸函数:预不变拟凸函数和半严格预不变拟凸函数,并得到了它们的3个性质.这些性质包括一定条件下判别半严格预不变拟凸函数的一个新的充分条件以及复合函数的预不变拟凸性,最后还讨论了半严格预不变拟凸函数在数学规划中的一个重要应用. 展开更多
关键词 预不变拟凸函数 半严格预不变拟凸函数 复合函数 数学规划问题(MP)
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High-density fiber optic array technology and its applica- tions in functional genomic studies
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作者 Jianbing Fan Diping Che +2 位作者 Chanfeng Zhao Lixin Zhou Wenyi Feng 《Chinese Science Bulletin》 SCIE EI CAS 2003年第18期1903-1905,共3页
关键词 in on of is High-density fiber optic array technology and its applica STUDIES tions in functional genomic
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Two Genera tions of Composers:Lei and His Daughter
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作者 BIAN WEN PAN ZHONGMING 《Women of China》 1997年第10期32-33,共2页
WHY are the flowers so red? Why so red? As red as a burning fire, It symbolizes purified friendship and love……
关键词 Two Genera tions of Composers:Lei and His Daughter
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一种适用于压气机非定常流动的相位滞后算法
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作者 严明 孙立 刘相凤 《航空动力学报》 EI CAS CSCD 北大核心 2008年第1期100-105,共6页
应用相位滞后边界条件,以1∶1的转、静叶计算域,在不改变转子尾迹及静子势干扰的频率的条件下,计算叶轮机非定常流场.以NASA stage 67为算例,计算结果与实验数据相吻合,表明采用的方法具有较大的工程实用性.
关键词 航空 航天推进系统 压气机 非定常 Navier—Stokes方程 相位滞后 并行
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因素空间理论与知识表示的数学框架(Ⅷ)─—变权综合原理 被引量:264
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作者 李洪兴 《模糊系统与数学》 CSCD 1995年第3期1-9,共9页
本文是文[1-7]的继续,研究变权综合问题,从确定变权的经验公式入手引出了变权原理,给出了变权的公理化定义,讨论了与之有关的均衡函数及其梯度向量。
关键词 因素空间 知识表示 变权综合 均衡函数 数学框架
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后路BAK椎间融合术治疗腰椎滑脱症的并发症分析 被引量:86
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作者 陈亮 唐天驷 +4 位作者 杨惠林 邱勇 徐杰 蒋兴良 马仁治 《中华骨科杂志》 CAS CSCD 北大核心 2002年第6期337-339,342,共4页
目的统计和分析后路BAK椎间融合器治疗腰椎滑脱症的并发症。方法对118例腰椎峡部崩裂性滑脱患者行后路BAK椎间融合术,统计术中、术后并发症(包括硬脊膜撕裂,神经根损伤,融合器位置不佳,融合器后移、沉陷和继发性粘连性蛛网膜炎等),分析... 目的统计和分析后路BAK椎间融合器治疗腰椎滑脱症的并发症。方法对118例腰椎峡部崩裂性滑脱患者行后路BAK椎间融合术,统计术中、术后并发症(包括硬脊膜撕裂,神经根损伤,融合器位置不佳,融合器后移、沉陷和继发性粘连性蛛网膜炎等),分析原因并探讨预防措施。结果118例患者中,术中并发症13例,占11%,其中硬脊膜撕裂4例(3.4%),神经根损伤3例(2.5%),BAK椎间融合器位置不佳9例(7.6%),2例硬脊膜撕裂和1例神经根损伤同时存在融合器位置不佳;术后并发症9例,占7.6%,其中融合器后移3例(2.5%),融合器沉陷4例(3.4%),继发性粘连性蛛网膜炎2例(1.7%),部分或可疑不融合5例(4.2%),2例融合器后移和1例沉陷均呈部分或可疑不融合,2例融合器沉陷伴继发性粘连性蛛网膜炎。结论后路BAK椎间融合术有一定的创新性和优越性,但手术创伤大,技术要求高,可能发生各种并发症,应严格掌握手术适应证并规范手术操作。 展开更多
关键词 后路BAK椎间融合术 治疗 腰椎滑脱症 并发症 脊椎前移
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