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Results Involving Partial Differential Equations and Their Solution by Certain Integral Transform
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作者 Rania Saadah Mohammed Amleh +2 位作者 Ahmad Qazza Shrideh Al-Omari Ahmet Ocak Akdemir 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1593-1616,共24页
In this study,we aimto investigate certain triple integral transformand its application to a class of partial differentialequations.We discuss various properties of the new transformincluding inversion, linearity, exi... In this study,we aimto investigate certain triple integral transformand its application to a class of partial differentialequations.We discuss various properties of the new transformincluding inversion, linearity, existence, scaling andshifting, etc. Then,we derive several results enfolding partial derivatives and establish amulti-convolution theorem.Further, we apply the aforementioned transform to some classical functions and many types of partial differentialequations involving heat equations,wave equations, Laplace equations, and Poisson equations aswell.Moreover,wedraw some figures to illustrate 3-D contour plots for exact solutions of some selected examples involving differentvalues in their variables. 展开更多
关键词 ARA transform double ARA transform triple ARA transform partial differential equations integral transform
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Study on Transformation of Ideas of Environmental Protection Administration and Construction of Ecological Civilization in China 被引量:1
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作者 Fu Baorong Yang Tao +4 位作者 He Zhe Zuo Shiwen Gu Chunyu Liu Song Zhang Runjie 《Meteorological and Environmental Research》 CAS 2017年第3期15-17,21,共4页
The transformation process of ideas of environmental protection administration in China was introduced firstly,and then the connotation and construction of ecological civilization were analyzed.
关键词 ideas of environmental protection ADMINISTRATION transformation Construction of ECOLOGICAL CIVILIZATION
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New two-fold integration transformation for the Wigner operator in phase space quantum mechanics and its relation to operator ordering 被引量:2
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作者 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期42-49,共8页
Using the Weyl ordering of operators expansion formula (Hong-Yi Fan, J. Phys.A 25 (1992) 3443) this paper finds a kind of two-fold integration transformation about the Wigner operator △( q',p) q-number transf... Using the Weyl ordering of operators expansion formula (Hong-Yi Fan, J. Phys.A 25 (1992) 3443) this paper finds a kind of two-fold integration transformation about the Wigner operator △( q',p) q-number transform) in phase space quantum mechanics,∫∫∞-∞dp'dq'/π △(q',p')e-2i( p-p')( q-q')=δ( p-P)δ( q-Q),∫∫∞-∞dqdpδ(p-P)δ(q-Q)e2i(p-p')(q-q')=△(q',p'),whereQ,P are the coordinate and momentum operators, respectively. We apply it to study mutual converting formulae among Q-P ordering, P-Q ordering and Weyl ordering of operators. In this way, the contents of phase space quantum mechanics can be enriched. The formula of the Weyl ordering of operators expansion and the technique of integration within the Weyl ordered product of operators are used in this discussion. 展开更多
关键词 Wigner operator Weyl ordering two-fold integration transformation
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A New Kind of Two-Fold Integration Transformation in Phase Space and Its Uses in Weyl Ordering of Operators 被引量:3
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作者 FAN Hong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期935-937,共3页
We propose a new two-fold integration transformation in p-q phase space∫∫_(-∞)~∞ (dqdq/π) e^(2i(p-x)(q-y))f(p,q)2≡G(x,y),which possesses some well-behaved transformation properties.We apply this transformation t... We propose a new two-fold integration transformation in p-q phase space∫∫_(-∞)~∞ (dqdq/π) e^(2i(p-x)(q-y))f(p,q)2≡G(x,y),which possesses some well-behaved transformation properties.We apply this transformation to the Weyl ordering ofoperators,especially those Q-P ordered and P-Q ordered operators. 展开更多
关键词 积分转换 相位空间 有序化 数学
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THE INTEGRAL TYPE GAUGE TRANSFORMATION AND THE ADDITIONAL SYMMETRY FOR THE CONSTRAINED KP HIERARCHY 被引量:2
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作者 程纪鹏 贺劲松 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1111-1121,共11页
In this paper, the compatibility between the integral type gauge transformation and the additional symmetry of the constrained KP hierarchy is given. And the string-equation constraint in matrix models is also derived.
关键词 constrained KP hierarchy integral type gauge transformation additional symmetry.
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A complementary integrated Transformer network for hyperspectral image classification
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作者 Diling Liao Cuiping Shi Liguo Wang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第4期1288-1307,共20页
In the past,convolutional neural network(CNN)has become one of the most popular deep learning frameworks,and has been widely used in Hyperspectral image classification tasks.Convolution(Conv)in CNN uses filter weights... In the past,convolutional neural network(CNN)has become one of the most popular deep learning frameworks,and has been widely used in Hyperspectral image classification tasks.Convolution(Conv)in CNN uses filter weights to extract features in local receiving domain,and the weight parameters are shared globally,which more focus on the highfrequency information of the image.Different from Conv,Transformer can obtain the long‐term dependence between long‐distance features through modelling,and adaptively focus on different regions.In addition,Transformer is considered as a low‐pass filter,which more focuses on the low‐frequency information of the image.Considering the complementary characteristics of Conv and Transformer,the two modes can be integrated for full feature extraction.In addition,the most important image features correspond to the discrimination region,while the secondary image features represent important but easily ignored regions,which are also conducive to the classification of HSIs.In this study,a complementary integrated Transformer network(CITNet)for hyperspectral image classification is proposed.Firstly,three‐dimensional convolution(Conv3D)and two‐dimensional convolution(Conv2D)are utilised to extract the shallow semantic information of the image.In order to enhance the secondary features,a channel Gaussian modulation attention module is proposed,which is embedded between Conv3D and Conv2D.This module can not only enhance secondary features,but suppress the most important and least important features.Then,considering the different and complementary characteristics of Conv and Transformer,a complementary integrated Transformer module is designed.Finally,through a large number of experiments,this study evaluates the classification performance of CITNet and several state‐of‐the‐art networks on five common datasets.The experimental results show that compared with these classification networks,CITNet can provide better classification performance. 展开更多
关键词 complementary integrated transformer module convolutional neural network Gaussian modulation transformER
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Radar fast long-time coherent integration via TR-SKT and robust sparse FRFT
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作者 CHEN Xiaolong GUAN Jian +2 位作者 ZHENG Jibin ZHANG Yue YU Xiaohan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第5期1116-1129,共14页
Long-time coherent integration(LTCI)is an effective way for radar maneuvering target detection,but it faces the problem of a large number of search parameters and large amount of calculation.Realizing the simultaneous... Long-time coherent integration(LTCI)is an effective way for radar maneuvering target detection,but it faces the problem of a large number of search parameters and large amount of calculation.Realizing the simultaneous compensation of the range and Doppler migrations in complex clutter back-ground,and at the same time improving the calculation efficiency has become an urgent problem to be solved.The sparse transformation theory is introduced to LTCI in this paper,and a non-parametric searching sparse LTCI(SLTCI)based maneuvering target detection method is proposed.This method performs time reversal(TR)and second-order Keystone transform(SKT)in the range frequency&slow-time data to complete high-order range walk compensation,and achieves the coherent integra-tion of maneuvering target across range and Doppler units via the robust sparse fractional Fourier transform(RSFRFT).It can compensate for the nonlinear range migration caused by high-order motion.S-band and X-band radar data measured in sea clutter background are used to verify the detection performance of the proposed method,which can achieve better detection performance of maneuvering targets with less computational burden compared with several popular integration methods. 展开更多
关键词 radar maneuvering target detection sea clutter long-time coherent integration(LTCI) sparse transformation time reversal(TR) second-order Keystone transform(SKT)
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Thinking about Value Realization of Ecological Products under the Background of Urban-rural Integration in Chengdu“Western Control”Area
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作者 ZHANG Xuequan ZHANG Yi 《Journal of Landscape Research》 2023年第2期59-62,共4页
Chengdu's development strategy of“western control”has laid a solid ecological background for 8 western districts,cities and counties and cultivated good ecological resources.The integrated urban-rural developmen... Chengdu's development strategy of“western control”has laid a solid ecological background for 8 western districts,cities and counties and cultivated good ecological resources.The integrated urban-rural development in the new era will realize the balanced development of urban and rural areas and give full play to the value of rural ecological resources through the“powerful combination”of urban and rural areas.To realize the urban-rural integration and high-quality rural development in Chengdu“western control”area,it is necessary to enhance the awareness of ecological resources and ecological products,and carry out unified planning of ecological infrastructure,ecological material products and ecological service products in the whole“western control”area.Meantime,ecological restoration must be carried out scientifically,and scene design for value transformation of ecological products should be implemented innovatively. 展开更多
关键词 Western control Urban-rural integration Ecological products Ecological value transformation
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Practice and Exploration of Xijiang for the Deep Integration of Intangible Cultural Heritage and Tourism Development
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作者 Zhang Hongxi Li Tianyi 《China & The World Cultural Exchange》 2023年第4期16-19,共4页
The development of Intangible Cultural Heritage tourism in Xijiang Qianhu Miao Village has gone through a long process of exploration and innovation from scratch.By reinforcing the protection of the"Intangible Cu... The development of Intangible Cultural Heritage tourism in Xijiang Qianhu Miao Village has gone through a long process of exploration and innovation from scratch.By reinforcing the protection of the"Intangible Cultural Heritage"stilted building of the Miao Village,doing a good job with the"Intangible Cultural Heritage+"concept,and constantly innovating the inheritance and protection of Intangible Cultural Heritage,the rich Miao culture of Xijiang Qianhu Miao Village has been gradually transformed from a primitive traditional living custom to a productive tool for economic development,which has strongly promoted the high-quality development of the Miao cultural tourism industry. 展开更多
关键词 integration transformed TOURISM
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FTransCNN:基于模糊融合的Transformer-CNN不确定性医学图像分割模型
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作者 王海鹏 丁卫平 +3 位作者 黄嘉爽 鞠恒荣 曹金鑫 刘传升 《小型微型计算机系统》 CSCD 北大核心 2024年第6期1426-1435,共10页
准确的医学图像分割对于疾病的诊断和治疗至关重要,将多个模型提取的分割特征进行联合使用时存在异质性、不确定性等问题,针对这一问题,本文提出了一种基于模糊融合策略的Transformer-CNN模型(FTransCNN).首先以CNN和Transformer作为骨... 准确的医学图像分割对于疾病的诊断和治疗至关重要,将多个模型提取的分割特征进行联合使用时存在异质性、不确定性等问题,针对这一问题,本文提出了一种基于模糊融合策略的Transformer-CNN模型(FTransCNN).首先以CNN和Transformer作为骨干网络,并行提取图片的特征信息;其次使用通道注意力促进Transformer全局关键信息,使用空间注意力增强CNN特征局部细节;接着应用Hadamard乘积对来自两个分支特征之间的细粒度交互进行建模,用Choquet模糊积分抑制融合特征的异质性以及融合特征的不确定性;然后使用Fuzzy Attention Fusion Module(FAFM)分级上采样,有效地捕获低级空间特征和高级语义上下文;最后反卷积得到最终的分割结果.在Chest X-ray数据集、Kvasir-SEG数据集和DRIVE数据集上的实验效果表明,FTransCNN与其它深度分割模型相比,在分割任务上有更好的效果. 展开更多
关键词 CHOQUET模糊积分 模糊融合 医学图像分割 transformER CNN
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A FAMILY OF INTEGRABLE SYSTEMS OF LIOUVILLE AND LAX REPRESENTATION, DARBOUX TRANSFORMATIONS FOR ITS CONSTRAINED FLOWS
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作者 张玉峰 张鸿庆 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第1期26-34,共9页
A family of integrable systems of Liouville are obtained by, Tu pattern. Using higher-order potential-eigenfunction constraints, the integrable systems are factorized to two x- and t(n)-integrable Hamiltonian systems ... A family of integrable systems of Liouville are obtained by, Tu pattern. Using higher-order potential-eigenfunction constraints, the integrable systems are factorized to two x- and t(n)-integrable Hamiltonian systems whose Lax representation and three kinds of Darboux transformations are presented. 展开更多
关键词 integrable system potential-eigenfuction constraint Lax representation Darboux transformation
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MATHEMATICAL PROBLEMS IN THE INTEGRAL-TRANSFORMATION METHOD OF DYNAMIC CRACK
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作者 边文凤 王彪 贾宝贤 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第3期252-256,共5页
In the investigation on fracture mechanics,the potential function was introduced, and the moving differential equation was constructed. By making Laplace and Fourier transformation as well as sine and cosine transform... In the investigation on fracture mechanics,the potential function was introduced, and the moving differential equation was constructed. By making Laplace and Fourier transformation as well as sine and cosine transformation to moving differential equations and various responses, the dual equation which is constructed from boundary conditions lastly was solved. This method of investigating dynamic crack has become a more systematic one that is used widely. Some problems are encountered when the dynamic crack is studied. After the large investigation on the problems, it is discovered that during the process of mathematic derivation, the method is short of precision, and the derived results in this method are accidental and have no credibility.A model for example is taken to explain the problems existing in initial deriving process of the integral_transformation method of dynamic crack. 展开更多
关键词 potential function integral transform dynamic crack dual equation
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FOURIER TRANSFORMATION AND SINGULAR INTEGRALS ON SELF-SIMILAR MEASURE
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作者 Wu Baoyi Su Weiyi, Nanjing University, China Department of Mathematics Nanjing University Nanjing 210093 PRC 《Analysis in Theory and Applications》 1998年第4期102-114,共13页
This paper serves two purposes. One is to modify Strichartz's results with respect to the asymptotic averages of the Fourier transform of μ on , self-similar measure defined by Hutchinson. Another purpose is to c... This paper serves two purposes. One is to modify Strichartz's results with respect to the asymptotic averages of the Fourier transform of μ on , self-similar measure defined by Hutchinson. Another purpose is to consider a singular integral operator on μ and show that this op- erator is of type (p,p)(1<p<∞). 展开更多
关键词 SHOW FOURIER transformation AND SINGULAR integrALS ON SELF-SIMILAR MEASURE MATH APPI
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Asymptotics for Nonlinear Transformations of Fractionally Integrated Time Series
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作者 李松臣 张世英 《Transactions of Tianjin University》 EI CAS 2007年第5期387-390,共4页
The asymptotic theory for nonlinear transformations of fractionally integrated time series is developed.By the use of fractional Occupation Times Formula,various nonlinear functions of fractionally integrated series s... The asymptotic theory for nonlinear transformations of fractionally integrated time series is developed.By the use of fractional Occupation Times Formula,various nonlinear functions of fractionally integrated series such as ARFIMA time series are studied,and the asymptotic distributions of the sample moments of such functions are obtained and analyzed.The transformations considered in this paper includes a variety of functions such as regular functions,integrable functions and asymptotically homogeneous functions that are often used in practical nonlinear econometric analysis.It is shown that the asymptotic theory of nonlinear transformations of original and normalized fractionally integrated processes is different from that of fractionally integrated processes,but is similar to the asymptotic theory of nonlinear transformations of integrated processes. 展开更多
关键词 非线行转换 时间序列 分数 运动
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Optical complex integration-transform for deriving complex fractional squeezing operator
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作者 张科 范承玉 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第3期101-104,共4页
We find a new complex integration-transform which can establish a new relationship between a two-mode operator's matrix element in the entangled state representation and its Wigner function. This integration keeps... We find a new complex integration-transform which can establish a new relationship between a two-mode operator's matrix element in the entangled state representation and its Wigner function. This integration keeps modulus invariant and therefore invertible. Based on this and the Weyl–Wigner correspondence theory, we find a two-mode operator which is responsible for complex fractional squeezing transformation. The entangled state representation and the Weyl ordering form of the two-mode Wigner operator are fully used in our derivation which brings convenience. 展开更多
关键词 integration-transform TWO-MODE ENTANGLED state Weyl–Wigner CORRESPONDENCE theory
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On How to Achieve the Scientific Transformation From College Integral English to Academic English
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作者 LIU Xu-liang 《Sino-US English Teaching》 2013年第7期543-547,共5页
关键词 大学英语教学 学术研究 积分 教学改革 科学 中国经济 语言能力 教育国际化
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Agrobacterium-Mediated Transformation of Rice: Constraints and Possible Solutions 被引量:7
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作者 Sulaiman MOHAMMED Azman Abd SAMAD Zaidah RAHMAT 《Rice science》 SCIE CSCD 2019年第3期133-146,共14页
Genetic transformation of rice(Oryza sativa L.) by introducing beneficial traits is now a central research instrument in plant physiology and a practical tool for plant improvement. Many approaches are verified for st... Genetic transformation of rice(Oryza sativa L.) by introducing beneficial traits is now a central research instrument in plant physiology and a practical tool for plant improvement. Many approaches are verified for stable introduction of foreign genes into the plant genome. The review examined the different constraints that limit the success of rice genetic transformation via Agrobacterium-mediated approach and suggested possible solutions. Explant identification, gene transfer technique and construct to tailor the integration, transgene expression without collateral to genetic damage and transformant selection are among the technical challenges affecting the rice transformation. Despite the contests, Agrobacteriummediated transformation system has been a better option for producing transgenic rice varieties because of its exact T-DNA processing and simple integration of low copy-number transgene. This information is necessary for improving the transformation system for recalcitrant rice varieties. 展开更多
关键词 RICE AGROBACTERIUM-MEDIATED transformation TISSUE CULTURE gene transfer T-DNA integration
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REFINEMENTS OF TRANSFORMATION INEQUALITIES FOR ZERO-BALANCED HYPERGEOMETRIC FUNCTIONS 被引量:9
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作者 王淼坤 褚玉明 《Acta Mathematica Scientia》 SCIE CSCD 2017年第3期607-622,共16页
In the article, we present some refinements of three classes of transformation inequalities for zero-balanced hypergeometric functions by use of the updated monotonicity criterion for the quotient of power series.
关键词 Gauss hypergeometric function complete elliptic integrals quadratic transfor-mation Ramanujan cubic transformation
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Dynamic response of axially moving Timoshenko beams: integral transform solution 被引量:4
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作者 安晨 苏健 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2014年第11期1421-1436,共16页
The generalized integral transform technique (GITT) is used to find a semianalytical numerical solution for dynamic response of an axially moving Timoshenko beam with clamped-clamped and simply-supported boundary co... The generalized integral transform technique (GITT) is used to find a semianalytical numerical solution for dynamic response of an axially moving Timoshenko beam with clamped-clamped and simply-supported boundary conditions, respectively. The implementation of GITT approach for analyzing the forced vibration equation eliminates the space variable and leads to systems of second-order ordinary differential equations (ODEs) in time. The MATHEMATICA built-in function, NDSolve, is used to numerically solve the resulting transformed ODE system. The good convergence behavior of the suggested eigenfunction expansions is demonstrated for calculating the transverse deflection and the angle of rotation of the beam cross-section. Moreover, parametric studies are performed to analyze the effects of the axially moving speed, the axial tension, and the amplitude of external distributed force on the vibration amplitude of axially moving Timoshenko beams. 展开更多
关键词 axially moving Timoshenko beam transverse vibration integral transform hybrid solution
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High-order perturbed corrections with scaling transformation 被引量:1
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作者 赵云辉 赵乘麟 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第8期2783-2789,共7页
The performance of the so-called superconvergent quantum perturbation theory (Wenhua Hal et al2000 Phys. Rev. A 61 052105) is investigated for the case of the ground-state energy of the helium-like ions. The scaling... The performance of the so-called superconvergent quantum perturbation theory (Wenhua Hal et al2000 Phys. Rev. A 61 052105) is investigated for the case of the ground-state energy of the helium-like ions. The scaling transformation τ → τ/Z applied to the Hamiltonian of a two-electron atomic ion with a nuclear charge Z (in atomic units). Using the improved Rayleigh-SchrSdinger perturbation theory based on the integral equation to helium-like ions in the ground states and treating the electron correlations as perturbations, we have performed a third-order perturbation calculation and obtained the second-order corrected wavefunctions consisting of a few terms and third-order energy corrections. We find that third-order and higher-order energy corrections are improved with decreasing nuclear charge. This result means that the former is quadratically integrable and the latter is physically meaningful. The improved quantum perturbation theory fits the higher-order perturbation case. This work shows that it is a development on the quantum perturbation problem of helium-like systems. 展开更多
关键词 integral equation scaling transformation higher-order perturbation
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