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英语V+To+Infinitive与V+To+V-ing结构的对比分析
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作者 周芬 《韶关学院学报》 2012年第7期58-62,共5页
英语v+to+infinitive与v+to+v-ing结构极易发生混淆。在句法上,v+to+infinitive结构中的to+infinitive要么是CP,要么是TP,而v+to+v-ing结构中的to+v-ing是介词短语PP。从语义角度来说,我们可以用主动词提示的时间做参照,to+infinitive... 英语v+to+infinitive与v+to+v-ing结构极易发生混淆。在句法上,v+to+infinitive结构中的to+infinitive要么是CP,要么是TP,而v+to+v-ing结构中的to+v-ing是介词短语PP。从语义角度来说,我们可以用主动词提示的时间做参照,to+infinitive所蕴含事件的时间要么发生在主动词时间之后或是与之同时发生,而to v-ing所蕴含的事件可以发生在主动词时间之前,之后或同时发生。另外,与to+infinitive结构不同的是v-ing结构更加倾向强调所发生事件的内部组成成分,所持续的时间和展开的方式等。 展开更多
关键词 v+to+infinitive结构 v+to+v-ing结构 句法 语义
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A Syntactic Study on Bare Infinitive and Infinitival to
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作者 刘静 《海外英语》 2014年第10X期239-240,共2页
Infinitives which consist of bare infinitive and infinitival to are imperative in linguistic studies.And both of the two kinds of infinitives do not indicate person,tense and number.This research aims to analyze the p... Infinitives which consist of bare infinitive and infinitival to are imperative in linguistic studies.And both of the two kinds of infinitives do not indicate person,tense and number.This research aims to analyze the properties,similarities and differences between bare infinitive and infinitival to from the perspective of syntax.Thus,it enables us to attain a uniform characterization of the infinitival to and bare infinitive on the syntactic level and help us to understand these two kinds of infinitives better. 展开更多
关键词 BARE infinitive infinitival to SIMILARITIES differ
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Ultrasonic wind velocity measurement based on DSP 被引量:10
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作者 唐慧强 黄惟一 +1 位作者 李萍 吕清华 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期20-23,共4页
Ultrasonic transmitting, receiving and amplifying circuits are designed. Thereceived signals are sampled with the high speed ADC (analog-to-digital converter), and dealt withthe DSP (digital signal processing). A forw... Ultrasonic transmitting, receiving and amplifying circuits are designed. Thereceived signals are sampled with the high speed ADC (analog-to-digital converter), and dealt withthe DSP (digital signal processing). A forward-backward IIR (infinitive impulse response) filterwith no delay is designed to filter the sampled data, and series A and B are achieved by narrow andwide band filtering, respectively. In series A, the start point of the cycle first exceeding thethreshold is calculated accuratelyby interpolation, and the start cycle is detected by fittingcycles in series A and its inversion A' to cycles in B with variance analysis. Therefore, the startpoint of the start cycle is calculated precisely. By deriving the relationships between the traveltime in the opposite directions of three axes and the airflow velocities, the wind velocity anddirection are calculated. Experiments show that the reliability and the precision are improved, andthe circuits are simplified. 展开更多
关键词 ULTRASONICS IIR (infinitive impulse response) filter DSP (digital signalprocessing) wind velocity
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Advances in integrated polarization detectors with innovative features
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作者 BU Yong-Hao ZHOU Jing +8 位作者 DENG Jie WANG Ruo-Wen YE Tao SHI Meng-Die HUANG Jun-Wei ZHANG Yu-Jie NING Jun LU Wei CHEN Xiao-Shuang 《红外与毫米波学报》 北大核心 2025年第3期371-383,共13页
The polarization properties of light are widely applied in imaging,communications,materials analy⁃sis,and life sciences.Various methods have been developed that can measure the polarization information of a target.How... The polarization properties of light are widely applied in imaging,communications,materials analy⁃sis,and life sciences.Various methods have been developed that can measure the polarization information of a target.However,conventional polarization detection systems are often bulky and complex,limiting their poten⁃tial for broader applications.To address the challenges of miniaturization,integrated polarization detectors have been extensively explored in recent years,achieving significant advancements in performance and functionality.In this review,we focus mainly on integrated polarization detectors with innovative features,including infinitely high polarization discrimination,ultrahigh sensitivity to polarization state change,full Stokes parameters measure⁃ment,and simultaneous perception of polarization and other key properties of light.Lastly,we discuss the oppor⁃tunities and challenges for the future development of integrated polarization photodetectors. 展开更多
关键词 integrated polarization detector infinite polarization extinction ratio polarization state change detection full-Stokes multidimensional detection
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Countability of Infinite Paths in the Infinity Tree: Proof of the Continuum Hypothesis in a Non-Cantorian Infinity Theory
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作者 Philip C. Jackson 《Advances in Pure Mathematics》 2025年第1期73-90,共18页
A previous paper showed that the real numbers between 0 and 1 could be represented by an infinite tree structure, called the ‘infinity tree’, which contains only a countably infinite number of nodes and arcs. This p... A previous paper showed that the real numbers between 0 and 1 could be represented by an infinite tree structure, called the ‘infinity tree’, which contains only a countably infinite number of nodes and arcs. This paper discusses how a finite-state Turing machine could, in a countably infinite number of state transitions, write all the infinite paths in the infinity tree to a countably infinite tape. Hence it is argued that the real numbers in the interval [0, 1] are countably infinite in a non-Cantorian theory of infinity based on Turing machines using countably infinite space and time. In this theory, Cantor’s Continuum Hypothesis can also be proved. And in this theory, it follows that the power set of the natural numbers P(ℕ) is countably infinite, which contradicts the claim of Cantor’s Theorem for the natural numbers. However, this paper does not claim there is an error in Cantor’s arguments that [0, 1] is uncountably infinite. Rather, this paper considers the situation as a paradox, resulting from different choices about how to represent and count the continuum of real numbers. 展开更多
关键词 INFINITY Countable UNCOUNTABLE Diagonalization Real Numbers Infinity Tree Continuum Hypothesis Turing Machine Infinite Time Turing Machine Non-Cantorian
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ON THE MEASURE CONCENTRATION OF INFINITELY DIVISIBLE DISTRIBUTIONS
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作者 Jing ZHANG Zechun HU Wei SUN 《Acta Mathematica Scientia》 2025年第2期473-492,共20页
Let I be the set of all infinitely divisible random variables with finite second moments,I_(0)={X∈I;Var(X)>0},P_(I)=inf_(x∈I)P{|X-E[X]|≤√Var(X)}and P_(I_(0))=inf P{|X-E[X]|<√Var(X)}.Firstly,we prove that P_... Let I be the set of all infinitely divisible random variables with finite second moments,I_(0)={X∈I;Var(X)>0},P_(I)=inf_(x∈I)P{|X-E[X]|≤√Var(X)}and P_(I_(0))=inf P{|X-E[X]|<√Var(X)}.Firstly,we prove that P_(I)≥P_(I_(0))>0.Secondly,we find_(x∈I_(0))the exact values of inf P{|X-E[X]|≤√Var(X)}and inf P{|X-E[X]|<√Var(X)}for the cases that J is the set of all geometric random variables,symmetric geometric random variables,Poisson random variables and symmetric Poisson random variables,respectively.As a consequence,we obtain that P_(I)≤e^(-1)^(∞)∑_(k=0)1/2^(2k)(k!)^(2)≈0.46576 and P_(I_(0))≤e^(-1)≈0.36788. 展开更多
关键词 measure concentration infinitely divisible distribution geometric distribution Poisson distribution Berry-Esseen theorem
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Calculation algorithm for the space charge force of a train with infinite bunches
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作者 San-Hai Ren Hong-Yu Li +5 位作者 Jia-Ru Shi Hao Zha Wei-Hang Gu Qiang Gao Qian Tan Huai-Bi Chen 《Nuclear Science and Techniques》 2025年第6期13-25,共13页
Industrial linear accelerators often contain many bunches when their pulse widths are extended to microseconds.As they typically operate at low electron energies and high currents,the interactions among bunches cannot... Industrial linear accelerators often contain many bunches when their pulse widths are extended to microseconds.As they typically operate at low electron energies and high currents,the interactions among bunches cannot be neglected.In this study,an algorithm is introduced for calculating the space charge force of a train with infinite bunches.By utilizing the ring charge model and the particle-in-cell(PIC)method and combining analytical and numerical methods,the proposed algorithm efficiently calculates the space charge force of infinite bunches,enabling the accurate design of accelerator parameters and a comprehensive understanding of the space charge force.This is a significant improvement on existing simulation software such as ASTRA and PARMELA that can only handle a single bunch or a small number of bunches.The PIC algorithm is validated in long drift space transport by comparing it with existing models,such as the infinite-bunch,ASTRA single-bunch,and PARMELA several-bunch algorithms.The space charge force calculation results for the external acceleration field are also verified.The reliability of the proposed algorithm provides a foundation for the design and optimization of industrial accelerators. 展开更多
关键词 Particle-in-cell method Space charge force ALGORITHM Infinite bunches
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Seismic response and vulnerability assessment of the pile-supported bridge pier in seasonally frozen regions
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作者 Yu Shengsheng Zhang Mingyi +1 位作者 Zhang Xiyin Wang Wanping 《Earthquake Engineering and Engineering Vibration》 2025年第2期493-507,共15页
Here,a seismic-response analysis model was proposed for evaluating the nonlinear seismic response of a pile-supported bridge pier under frozen and thawed soil conditions.The effect of a seasonally frozen soil layer on... Here,a seismic-response analysis model was proposed for evaluating the nonlinear seismic response of a pile-supported bridge pier under frozen and thawed soil conditions.The effect of a seasonally frozen soil layer on the seismic vulnerability of a pile-supported bridge pier was evaluated based on reliability theory.Although the frozen soil layer inhibited the seismic response of the ground surface to a certain extent,it exacerbated the acceleration response at the bridge pier top owing to the low radiation damping effect of the frozen soil layer.Furthermore,the frozen soil layer reduced the lateral displacement of the bridge pier top relative to the ground surface by approximately 80%,thereby preventing damage caused by earthquakes,such as falling girders.Compared to the thawed state of the ground surface,the bending moment of the bridge pier in frozen ground increases.However,the bending moment of the pile foundation in frozen ground decreases,thereby lessening the seismic vulnerability of the bridge pile foundation.The results of this can provide a reference for the seismic response analysis and seismic risk assessment of pile-supported bridges in seasonally frozen regions. 展开更多
关键词 pile-supported bridge pier seasonally frozen region infinite element boundary nonlinear seismic response seismic vulnerability
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Bound States in the Continuum of Infinite Quality Factor in Finite Unit Cells
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作者 Hua-Wei Liang Yuan-Zhi Liu +2 位作者 Yu-Jia Zeng Yang-Jian Cai Ting-Yin Ning 《Chinese Physics Letters》 2025年第8期38-53,共16页
A theory based on the superposition principle is developed to uncover the basic physics of wave behavior in a finite grating of N unit cells.The theory reveals that bound states in the continuum(BICs)of infinite quali... A theory based on the superposition principle is developed to uncover the basic physics of wave behavior in a finite grating of N unit cells.The theory reveals that bound states in the continuum(BICs)of infinite quality factor(Q-factor)can be supported by such a grating when perfect reflection is introduced at its boundaries.If geometrical perturbations are introduced into the structure,the dark BICs transform into bright quasi-BICs with finite Q-factor,maintaining spectral characteristics nearly identical to those of quasi-BICs supported by infinite gratings.When the boundaries are replaced with high-reflectivity metallic mirrors,the Q-factor of the resonant mode is reduced to be finite;however,it can be much larger than that in the corresponding nanostructure with open boundaries and can be tuned over a large range by varying the number of unit cells or boundary conditions. 展开更多
关键词 Superposition Principle wave behavior perfect reflection Finite Unit Cells geometrical perturbations dark bics Bound States Continuum Infinite Quality Factor
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A novel approach to visual image encryption:2D hyperchaos,variable Josephus,and 3D diffusion
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作者 Yan Hong Xinyan Duan +2 位作者 Jingming Su Zhaopan Wang Shihui Fang 《Chinese Physics B》 2025年第4期335-352,共18页
With the development of the Internet,image encryption technology has become critical for network security.Traditional methods often suffer from issues such as insufficient chaos,low randomness in key generation,and po... With the development of the Internet,image encryption technology has become critical for network security.Traditional methods often suffer from issues such as insufficient chaos,low randomness in key generation,and poor encryption efficiency.To enhance performance,this paper proposes a new encryption algorithm designed to optimize parallel processing and adapt to images of varying sizes and colors.The method begins by using SHA-384 to extract the hash value of the plaintext image,which is then processed to determine the chaotic system’s initial value and block size.The image is padded and divided into blocks for further processing.A novel two-dimensional infinite collapses hyperchaotic map(2DICHM)is employed to generate the intra-block scrambling sequence,while an improved variable Joseph traversal sequence is used for inter-block scrambling.After removing the padding,3D forward and backward shift diffusions,controlled by the 2D-ICHM sequences,are applied to the scrambled image,producing the ciphertext.Simulation results demonstrate that the proposed algorithm outperforms others in terms of entropy,anti-noise resilience,correlation coefficient,robustness,and encryption efficiency. 展开更多
关键词 SHA-384 two-dimensional infinite collapses hyperchaotic map(2D-ICHM) variable Joseph traversal 3D forward shift diffusion
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模糊有限自动机的乘积覆盖性 被引量:3
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作者 陈乾 涂道兴 莫智文 《模糊系统与数学》 CSCD 北大核心 2011年第2期21-28,共8页
推广模糊有限自动机的有限积,包括direct infinite乘积、cascade infinite乘积和wreath infinite乘积。进而讨论它们之间的关系,得到乘积覆盖性等代数性质。
关键词 模糊有限自动机 覆盖 DIRECT infinite乘积 CASCADE infinite乘积 Wreath infinite乘积
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Explicit solution of diffusion master equation under the action of linear resonance force via the thermal entangled state representation 被引量:3
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作者 姚飞 王继锁 徐天牛 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期98-101,共4页
Using the well-behaved features of the thermal entangled state representation, we solve the diffusion master equation under the action of a linear resonance force, and then obtain the infinitive operator-sum represent... Using the well-behaved features of the thermal entangled state representation, we solve the diffusion master equation under the action of a linear resonance force, and then obtain the infinitive operator-sum representation of the density operator. This approach may also be effective for treating other master equations. Moreover, we find that the initial pure coherent state evolves into a mixed thermal state after passing through the diffusion process under the action of the linear resonance force. 展开更多
关键词 diffusion process linear resonance force thermal state representation infinitive operator-sum representation
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Analytical and numerical investigations of displaced thermal state evolutions in a laser process 被引量:2
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作者 杜传勋 孟祥国 +1 位作者 张冉 王继锁 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第12期102-108,共7页
We investigate how displaced thermal states (DTSs) evolve in a laser channel. Remarkably, the initial DTS, an example of a mixed state, still remains mixed and thermal. At long times, they finally decay to a highly ... We investigate how displaced thermal states (DTSs) evolve in a laser channel. Remarkably, the initial DTS, an example of a mixed state, still remains mixed and thermal. At long times, they finally decay to a highly classical thermal field only related to the laser parameters κ and g. The normal ordering product of density operator of the DTS in the laser channel leads to obtaining the analytical time-evolution expressions of the photon number, Wigner function, and von Neumann entropy. Also, some interesting results are presented via numerically investigating these explicit time-dependent expressions. 展开更多
关键词 displaced thermal state laser process infinitive operator-sum representation photon number Wigner function von Neumann entropy
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自适应滤波器在超宽带穿墙雷达中的应用研究
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作者 吴建斌 凌毓涛 +1 位作者 吴建平 王振亚 《计算机工程与应用》 CSCD 2014年第16期202-205,共4页
作为一种新型探测和定位墙后人体目标的方法,超宽带穿墙雷达在军事和民用多个领域得到了广泛的应用。由于目标信号经常被强背景噪声所淹没,为实现动目标检测,需寻求一种有效的背景相消方法以凸显动目标信号,提高动目标检测和定位的精度... 作为一种新型探测和定位墙后人体目标的方法,超宽带穿墙雷达在军事和民用多个领域得到了广泛的应用。由于目标信号经常被强背景噪声所淹没,为实现动目标检测,需寻求一种有效的背景相消方法以凸显动目标信号,提高动目标检测和定位的精度。在研究回波信号特点的基础上,考虑到无限冲击响应(IIR)滤波器和自适应滤波器的优点,提出采用基于IIR的自适应滤波器背景噪声相消的方法,抑制回波信号中的噪声。为验证方法的有效性,采用该方法对利用SIR20雷达收集的实测数据进行了相关处理。从结果看,该方法能有效抑制背景噪声,凸显目标信号,为目标的检测和定位奠定了良好的基础。 展开更多
关键词 超宽带穿墙雷达 自适应 无线冲击响应 INFINITE IMPULSE Response(IIR)
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浅谈巧学动词的非限定形式
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作者 陈桂娟 《科技信息》 2006年第S3期123-124,共2页
动词有一种不受主语限制的形式,叫做动词的非限定形式(Non- Finite Forms of the Verb)。这种形式不能独立作谓语.所以也叫非谓语动词.但可以和助动词或情态动词等构成谓语,还可以在句子中充当主语、宾语、定语、状语、表语等。其形... 动词有一种不受主语限制的形式,叫做动词的非限定形式(Non- Finite Forms of the Verb)。这种形式不能独立作谓语.所以也叫非谓语动词.但可以和助动词或情态动词等构成谓语,还可以在句子中充当主语、宾语、定语、状语、表语等。其形式有三种:动名词、分词、不定式。中学英语教材从初中到高中都涉及非谓语动词的教学内容。尽管教师采取了分散难点、各个攻破的方法教学该语法项目,但学生仍然搞不清三种非谓语动词的区别,在学习、理解及运用此知识点时感到困难。 展开更多
关键词 Non-Finite VERBS infinitive GERUND PRESENT Partici
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Research on Post-classical Narrative Focalization in The Love Wife
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作者 郭丽莉 《海外英语》 2013年第16期171-172,共2页
The Love Wife is considered to be a breakthrough of Gish Jen either in theme and narrative techniques. While, as the critical distinguished narrative technique from the perspective of Post-classical Narratology, the i... The Love Wife is considered to be a breakthrough of Gish Jen either in theme and narrative techniques. While, as the critical distinguished narrative technique from the perspective of Post-classical Narratology, the infinitive internal focalization will be analyzed in this paper so as to investigate the five protagonists'search for their own identity and eagerness to achieve the acknowledge both from their family and the whole society. Furthermore, the author's own view in breaking up the barrier and discrimination around the world is also well-illustrated. 展开更多
关键词 infinitive internal focalization IDENTITY
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WSP系统与辨识
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作者 陈亚陵 《厦门大学学报(自然科学版)》 CAS 1988年第1期1-7,共7页
本文把投影算子的加权和表示方法引入无穷维线性系统,产生投影加权和系统,即简称为WSP系统,为无穷维系统辨识问题提供一种方便的模型结构方式,文中讨论了WSP系统的产生过程以及其系统辨识问题.
关键词 WSP systems Infinite dimensional IDENTIFICATION
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New approach for deriving the exact time evolution of the density operator for a diffusive anharmonic oscillator and its Wigner distribution function
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作者 孟祥国 王继锁 梁宝龙 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期146-151,共6页
Using thermal entangled state representation,we solve the master equation of a diffusive anharmonic oscillator(AHO) to obtain the exact time evolution formula for the density operator in the infinitive operator-sum ... Using thermal entangled state representation,we solve the master equation of a diffusive anharmonic oscillator(AHO) to obtain the exact time evolution formula for the density operator in the infinitive operator-sum representation.We present a new evolution formula of the Wigner function(WF) for any initial state of the diffusive AHO by converting the WF calculation into an overlap between two pure states in an enlarged Fock space.It is found that this formula is very convenient in investigating the WF's evolution of any known initial state.As applications,this formula is used to obtain the evolution of the WF for a coherent state and the evolution of the photon-number distribution of diffusive AHOs. 展开更多
关键词 diffusive anharmonic oscillator thermal entangled state representation infinitive operator-sum representation Wigner function
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《汉英大辞典》评介
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作者 张泉宝 《现代出版》 1995年第3期39-40,共2页
《汉英大辞典》评介张泉宝上海交通大学出版社出版的由吴光华主编的《汉英大辞典》(上、下卷),1500万字,是我国建国以来第一部规模最大,融文、理、工多学科于一体,兼有普通汉英词典和科技汉英词典的双重功能、方便而实用的大... 《汉英大辞典》评介张泉宝上海交通大学出版社出版的由吴光华主编的《汉英大辞典》(上、下卷),1500万字,是我国建国以来第一部规模最大,融文、理、工多学科于一体,兼有普通汉英词典和科技汉英词典的双重功能、方便而实用的大型汉英词典。同已有的汉英词典相比,... 展开更多
关键词 ACTIVE FORM PASSIVE in SENSE infinitive
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