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词义变化与语符间的结构关系 被引量:2
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作者 许静 《解放军外国语学院学报》 2000年第3期21-23,共3页
通过对词义“感染”现象和语义场中语义空间分布上的变化的分析,说明词义变化是语符间存在的两种结构关系──组合关系和聚合关系──在语言实际运用过程中变化的结果。
关键词 词义变化 的结构关系 词义“感染”现象 语义空分布的变化
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论音乐空间与建筑空间的对应性 被引量:9
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作者 王昀 《华中建筑》 2001年第4期47-52,共6页
本文论述了音乐空间与建筑空间的对应性关系。同时以此为基础对将乐谱这一视觉化了的音乐空间转组并移注于建筑空间的实验理论和操作方法进行了探讨和提示。
关键词 音乐空 建筑空 乐谱 间符 图式
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一种数字通信系统中的基带信号成形技术 被引量:2
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作者 秦文兵 江修富 曲炜 《装备指挥技术学院学报》 2004年第2期76-79,共4页
在现代通信技术中,为了适应高效利用频带资源的发展要求,提高通信系统的有效性、可靠性和实用性,迫切需要高质量、高效率的基带信号成形技术.根据软件无线电发展的方向和要求,介绍了通过对基带信号处理来提高频带效率,减少或消除无符号... 在现代通信技术中,为了适应高效利用频带资源的发展要求,提高通信系统的有效性、可靠性和实用性,迫切需要高质量、高效率的基带信号成形技术.根据软件无线电发展的方向和要求,介绍了通过对基带信号处理来提高频带效率,减少或消除无符号码间干扰(in sign interferer,ISI)的有效方法;提出了一种具有可操作性的全数字化升余弦(rise cosine,RC)滤波器,着重分析了该滤波器的实现方案和性能,并给出了其仿真和现场可编程门阵列(field programmable gate arry,FPGA)硬件设计结果;该技术对当前数字通信系统中基带信号成形技术的理论和实现具有一定的参考价值. 展开更多
关键词 软件无线电 升余弦滤波器 号码干扰 数字通信 无线电通信
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Extract the Output Signal Characteristics of DC-DC Converter Based on Fourier Descriptor
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作者 钟洁 于盛林 刘守生 《Journal of Southeast University(English Edition)》 EI CAS 2002年第4期336-340,共5页
The precondition of realizing feedback controlling DC DC converter to avoid chaotic state is to judge the behavior of the converter and take corresponding measures. In this paper, the output signals under different ci... The precondition of realizing feedback controlling DC DC converter to avoid chaotic state is to judge the behavior of the converter and take corresponding measures. In this paper, the output signals under different circuit parameters of the PWM buck converter have been analyzed. The method of using Fourier descriptor to extract output signals characteristics is put forward and proved to be a gist of identifying and classifying the behavior of DC DC converter. This method can establish a good foundation fo... 展开更多
关键词 DC DC converter periodic orbits v i phase space Fourier descriptor
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Different known guard intervals for single/multi-carrier transceiver
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作者 李玮 程时昕 陈明 《Journal of Southeast University(English Edition)》 EI CAS 2006年第1期11-15,共5页
To enhance the bandwidth efficiency of the guard interval (GI) assisted wireless communication system, an attractive scheme is proposed, which combines the functions of pilots and the GI together, so that the pilot ... To enhance the bandwidth efficiency of the guard interval (GI) assisted wireless communication system, an attractive scheme is proposed, which combines the functions of pilots and the GI together, so that the pilot resource used for estimating channel state is saved. Based on the proposed different known guard intervals (DKGI), the time-domain channel estimation can be simply applied on the receiver side. After channel estimation, the receiver can employ the cyclic convolution restoring (CCR) function to reconstruct the cyclical convolution relationship between the signal and the channel, by which the receiver can also achieve good performance through the conventional 1-tap frequency domain equalization (FDE). 展开更多
关键词 cyclic prefix zero padding fixed symbol padding channel estimation
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A VERTICAL LAYERED SPACE-TIME CODE AND ITS CLOSED-FORM BLIND SYMBOL DETECTION 被引量:1
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作者 Zhao Zheng Yin Qinye Zhang Hong Feng Aigang (Institute of Information Engineering, Xi’an .Jiaotong University, Xi’an 710049) 《Journal of Electronics(China)》 2003年第2期102-109,共8页
Vertical layered space-time codes have demonstrated the enormous potential to accommodate rapid flow data. Thus far, vertical layered space-time codes assumed that perfect estimates of current channel fading condition... Vertical layered space-time codes have demonstrated the enormous potential to accommodate rapid flow data. Thus far, vertical layered space-time codes assumed that perfect estimates of current channel fading conditions are available at the receiver. However, increasing the number of transmit antennas increases the required training interval and reduces the available time in which data may be transmitted before the fading coefficients change. In this paper, a vertical layered space-time code is proposed. By applying the subspace method to the layered space-time code, the symbols can be detected without training symbols and channel estimates at the transmitter or the receiver. Monte Carlo simulations show that performance can approach that of the detection method with the knowledge of the channel. 展开更多
关键词 Layered space-time code Array signal processing Subspace method Blind symbol detection
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Triaxial Shape, Signature Splitting, and Shape Coexistence in ^(127,129,131)Nd
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作者 DONG Bao-Guo MA Hai-Liang YAN Yu-Liang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期187-192,共6页
Signature splitting and shape coexistence at high spin in the neutron deficient nucleus ^129Nd are investigated with the configuration-dependent cranked Nilsson-Strutinsky approach. The calculated bands are compared w... Signature splitting and shape coexistence at high spin in the neutron deficient nucleus ^129Nd are investigated with the configuration-dependent cranked Nilsson-Strutinsky approach. The calculated bands are compared with the observed signature partner bands and very good agreement results at high spin are obtained. The observed deformed bands are confirmed as normal and highly deformed and their properties are explained theoretically. Terminating states in ^129Nd and other terminations are predicted. There is shape coexistence within the same configuration from lowspin states to high-spin states. Possible normal and highly deformed bands with rotation around the intermediate principal axis in several interesting configurations of ^129Nd are discussed. The experimental results for ^131Nd are simply discussed and the calculated bands are in good agreement with observed bands at high spin. TriaxiM shapes in ^127 Nd with a triaxial deformation of γ -12° are predicted and should be observed experimentally. The value of negative γ of π(h11/2)^4v(h11/2)^7 configuration increases with neutron number increasing in ^127,129,131Nd. The triaxial shape evolutions with neutron number increasing in ^127,129,131Nd and in ^126,128,130,132pr are explained by the strong driving force of specified single particle orbitals towards to triaxial shape. 展开更多
关键词 rotational structure triaxial shape signature splitting CONFIGURATION
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Prediction of metal futures price volatility and empirical analysis based on symbolic time series of high-frequency 被引量:1
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作者 Dan WU Jian-bai HUANG Mei-rui ZHONG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第6期1707-1716,共10页
The metal futures price fluctuation prediction model was constructed based on symbolic high-frequency time series using high-frequency data on the Shanghai Copper Futures Exchange from July 2014 to September 2018,and ... The metal futures price fluctuation prediction model was constructed based on symbolic high-frequency time series using high-frequency data on the Shanghai Copper Futures Exchange from July 2014 to September 2018,and the sample was divided into 194 histogram time series employing symbolic time series.The next cycle was then predicted using the K-NN algorithm and exponential smoothing,respectively.The results show that the trend of the histogram of the copper futures earnings prediction is gentler than that of the actual histogram,the overall situation of the prediction results is better,and the overall fluctuation of the one-week earnings of the copper futures predicted and the actual volatility are largely the same.This shows that the results predicted by the K-NN algorithm are more accurate than those predicted by the exponential smoothing method.Based on the predicted one-week price fluctuations of copper futures,regulators and investors in China’s copper futures market can timely adjust their regulatory policies and investment strategies to control risks. 展开更多
关键词 HIGH-FREQUENCY COPPER metal futures symbolic time series price fluctuation PREDICTION
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The Labors of the Months and the Zodiac Signs in the Cathedral of Otranto: An Iconographical Interpretation of the Symbols of Labor and Time 被引量:1
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作者 Liana De Girolami Cheney 《Cultural and Religious Studies》 2016年第11期682-709,共28页
In 1163, Archbishop Gionata, Abbot of the Monastery of San Nicola of Casole in Puglia (Apulia), commissioned Pantaleone, a learned monk and artist from the monastery, to decorate the pavement of the cathedral of Otr... In 1163, Archbishop Gionata, Abbot of the Monastery of San Nicola of Casole in Puglia (Apulia), commissioned Pantaleone, a learned monk and artist from the monastery, to decorate the pavement of the cathedral of Otranto with mosaics. This Italian Romanesque cathedral was dedicated to Santa Maria Annunziata or Saint Mary of The Annunciation. In the interior, the floor design in the shape of a tree contains an elaborate biblical program. The encyclopedic narrative of the mosaic symbolically unveils the meaning of the Tree of Life. The ieonography of the pavement's program combines biblical and pagan narratives evolving from a natural realm into a heavenly realm. The natural realm begins at the church's entrance with the symbolism of the earth-the roots of a tree-expanding through the nave and transept via the tree's trunk and its branches, culminating in the apse, at the end of the church, with the foliage oftbe top of the tree. This natural realm meets with the heavenly realm in two ways: at the crossing of the church or at the sacrificial altar, and at the apse of the church. Before reaching the altar or holy area, between the natural realm and the heavenly realm, the zodiac signs with the labors of the months are depicted. 展开更多
关键词 Tree of Life labors of the months zodiac signs CONSTELLATIONS SYMBOLISM
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Modified Fourier descriptor for shape feature extraction 被引量:1
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作者 张刚 马宗民 +1 位作者 牛连强 张纯明 《Journal of Central South University》 SCIE EI CAS 2012年第2期488-495,共8页
A modified Fourier descriptor was presented. Information from a local space can be used more efficiently. After the boundary pixel set of an object was computed, centroid distance approach was used to compute shape si... A modified Fourier descriptor was presented. Information from a local space can be used more efficiently. After the boundary pixel set of an object was computed, centroid distance approach was used to compute shape signature in the local space. A pair of shape signature and boundary pixel gray was used as a point in a feature space. Then, Fourier transform was used for composition of point information in the feature space so that the shape features could be computed. It is proved theoretically that the shape features from modified Fourier descriptors are invariant to translation, rotation, scaling, and change of start point. It is also testified by measuring the retrieval performance of the systems that the shape features from modified Fourier oescriptors are more discriminative than those from other Fourier descriptors. 展开更多
关键词 shape feature extraction Fourier descriptors centroid distance approach
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PERFORMANCE OF THREE STAGE TURBO-EQUALIZATION-DECODING
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作者 Kazi Takpaya 《Journal of Electronics(China)》 2003年第6期439-445,共7页
An increasing demand for high data rate transmission and protection over bandlimited channels with severe inter-symbol interference has resulted in a flurry of activity to improve channel equalization, In conjunction ... An increasing demand for high data rate transmission and protection over bandlimited channels with severe inter-symbol interference has resulted in a flurry of activity to improve channel equalization, In conjunction with equalization, channel coding-decoding can be employed to improve system performance. In this letter, the performance of the three stage turbo-equalization-decoding employing log maximum a posteriori probability is experimentally evaluated by a fading simulator. The BER is evaluated using various information sequence and interleaver sizes taking into account that the communication medium is a noisy inter symbol interference channel. 展开更多
关键词 Band-limited channel Inter-symbol interference Three stage turbo-equalization- decoding
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Geo-rough Space 被引量:12
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作者 WANG Shuliang LI Deren SHI Wenzhong WANG Xinzhou 《Geo-Spatial Information Science》 2003年第1期54-61,共8页
Rough set is a new approach to uncertainties in spatial analysis.In this paper,rough set symbols are simplified and standardized in terms of rough interpretation and specialized indication.Rough spatial entities and t... Rough set is a new approach to uncertainties in spatial analysis.In this paper,rough set symbols are simplified and standardized in terms of rough interpretation and specialized indication.Rough spatial entities and their topological relationships are also proposed in rough space,thus a universal intersected equation is developed,and rough membership function is further extended with the gray scale in our case study.We complete three works.First,a set of simplified rough symbols is advanced on the basis of existing rough symbols.Second,rough spatial entity is put forward to study the real world as it is,without forcing uncertainties into crisp set.Third,rough spatial topological relationships are studied by using rough matrix and their figures.The relationships are divided into three types,crisp entity and crisp entity (CC),rough entity and crisp entity (RC),and rough entity and rough entity (RR).A universal intersected equation is further proposed.Finally,the maximum and minimum maps of river thematic classification are generated via rough membership function and rough relationships in our case study. 展开更多
关键词 rough set rough spatial entity rough topological relationship rough symbols
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Research on characters of surrounding rock in complex geology conditions and supporting time 被引量:9
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作者 Yu Weijian Gao Qian +1 位作者 Zhai Shuhua Zhang Meihua 《Engineering Sciences》 EI 2008年第2期91-96,共6页
The methods combined by test, field monitoring and theoretical analysis were adopted to do the systemic research on the rock mass from micro-structure to macro-deformation, and rheological model of Jinchuan rock mass ... The methods combined by test, field monitoring and theoretical analysis were adopted to do the systemic research on the rock mass from micro-structure to macro-deformation, and rheological model of Jinchuan rock mass was established to discuss the reasonable supporting time. Resuhs show that supporting after suitable stress and displacement release can benefit for the long-term stability of surrounding rock. 展开更多
关键词 complex geological conditions surrounding rock characteristic test supporting time theological characteristic
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A 10Gb/s combined equalizer in 0.18μm CMOS technology for backplane communication
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作者 张明科 Hu Qingsheng 《High Technology Letters》 EI CAS 2015年第2期205-211,共7页
This paper presents a lOGb/s highspeed equalizer as the frontend of a receiver for backplane communication. The equalizer combines an analog equalizer and a twotap decisionfeedback equal izer in a halfrate structure t... This paper presents a lOGb/s highspeed equalizer as the frontend of a receiver for backplane communication. The equalizer combines an analog equalizer and a twotap decisionfeedback equal izer in a halfrate structure to reduce the intersymbolinterference (ISI) of the communication chan nel. By employing inductive peaking technique for the highfrequency boost circuit, the bandwidth and the boost of the analog equalizer are improved. The decisionfeedback equalizer optimizes the size of the CMLbased circuit such as D flipflops (DFF) and multiplex (MUX), shortening the feedback path delay and speeding up the operation considerably. Designed in the 0. 181μm CMOS technology, the equalizer delivers 10Gb/s data over 18in FR4 trace with 28dB loss while drawing 27mW from a 1.8V supply. The overall chip area including pads is 0. 6 -0.7mm2. 展开更多
关键词 analog equalizer decision feedback equalizer (DFE) inductive peaking current mode logic (CML)
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Multiverse and the Time State 被引量:2
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作者 Khaled (Moh'd Khalaf) Suleiman Alnobani 《Journal of Energy and Power Engineering》 2017年第3期160-163,共4页
This article is not inspired by any religion or quantum many-worlds interpretation. The mathematics of multiverse is presented here. The mass operator was introduced earlier by Alnobani. This operator is used here to ... This article is not inspired by any religion or quantum many-worlds interpretation. The mathematics of multiverse is presented here. The mass operator was introduced earlier by Alnobani. This operator is used here to deduce the time state. It is found that time has four states and those four states are orthogonal. Time is the constitution of any verse. Time has direction. Every orthogonal direction of time belongs to a verse. Past and future belong to opposite directions of time and they are arbitrary. Other verses are there by their own and not a probabilities of any other verse and if any similarity it is only a coincidence. Among applications of this thesis is travelling through groups of galaxies, or more or less. 展开更多
关键词 TIME MASS multiverse.
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Some Magnetized Bulk Viscous String Cosmological Models in Cylindrically Symmetric Inhomogeneous Universe with Variable Λ-Term 被引量:1
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作者 Anirudh Pradhan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期367-374,共8页
Some cylindrically symmetric inhomogeneous viscous fluid string cosmological models with magnetic field and cosmological term A varying with time are investigated. To get the deterministic solution, it has been assume... Some cylindrically symmetric inhomogeneous viscous fluid string cosmological models with magnetic field and cosmological term A varying with time are investigated. To get the deterministic solution, it has been assumed that the expansion (θ) in the model is proportional to the eigen value σ^11 of the shear tensor σ^ij. The value of cosmological constant for the model is found to be small and positive, which is supported by the results from recent supernovae Ia observations. The effect of bulk viscosity is to produce a change in perfect fluid and hence exhibits essential influence on the character of the solution. The physical and geometric properties of the models are also discussed in presence and absence of magnetic field. 展开更多
关键词 STRING inhomogeneous universe cylindrical symmetry variable cosmological term bulk viscosity
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NOVEL ICI CANCELLATION ALGORITHM IN OFDM SYSTEMS
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作者 XuChangqing ZhangXiaobo SongWentao 《Journal of Electronics(China)》 2004年第1期78-82,共5页
The Bit Error Rate (BER) caused by Inter Carrier Interference (ICI) increases greatly with the increase of frequency offset in Orthogonal Frequency Division Multiplexing (OFDM) systems. According to a typical OFDM sig... The Bit Error Rate (BER) caused by Inter Carrier Interference (ICI) increases greatly with the increase of frequency offset in Orthogonal Frequency Division Multiplexing (OFDM) systems. According to a typical OFDM signal model, this letter proves that the coefficient matrix of ICI is a unitary matrix whose inverse matrix is much easier to get, and then proposes a new ICI cancellation method with less computation complexity by sending typical pilot symbols. Compared with two existing ICI cancellation methods, self-cancellation and windowing cancellation, it is shown that the proposed algorithm can cancel ICI better and overcome the limitation of the two traditional methods. 展开更多
关键词 OFDM Inter-carrier interference Pilot symbol
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Finite Operators
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作者 Hadia Messaoudene 《Journal of Mathematics and System Science》 2013年第4期190-194,共5页
Let H be a separable infinite dimensional complex Hilbert space, and L(H) the algebra of all bounded linear operators on 3-t'. The class of finite operators is the class of operators for which the distance of the i... Let H be a separable infinite dimensional complex Hilbert space, and L(H) the algebra of all bounded linear operators on 3-t'. The class of finite operators is the class of operators for which the distance of the identity operator I and the derivation range is maximal; where the derivation range of the operator A is defined by δA;δA : L(H) -L(H) X- AX - XA. In this paper we present some properties of finite operators and give some classes of operators which are in the class of finite operators, and find for witch condition A ~ W is a finite operator in L(2-H H), and gave a g6neralisation of Stampflli theorem. 展开更多
关键词 Finite operator IDENTITY class R1 reduced approximate point spectrum.
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An approach to offline handwritten Chinese character recognition based on segment evaluation of adaptive duration
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作者 李国宏 施鹏飞 《Journal of Zhejiang University Science》 CSCD 2004年第11期1392-1397,共6页
This paper presents a methodology for off-line handwritten Chinese character recognition based on mergence of consecutive segments of adaptive duration. The handwritten Chinese character string is partitioned into a s... This paper presents a methodology for off-line handwritten Chinese character recognition based on mergence of consecutive segments of adaptive duration. The handwritten Chinese character string is partitioned into a sequence of consecutive segments, which are combined to implement dissimilarity evaluation within a sliding window whose durations are determined adaptively by the integration of shapes and context of evaluations. The average stroke width is estimated for the handwritten Chinese character string, and a set of candidate character segmentation boundaries is found by using the integration of pixel and stroke features. The final decisions on segmentation and recognition are made under minimal arithmetical mean dissimilarities. Experiments proved that the proposed approach of adaptive duration outperforms the method of fixed duration, and is very effective for the recognition of overlapped, broken, touched, loosely configured Chinese characters. 展开更多
关键词 Handwritten Chinese character Segmentation boundary SEGMENT DURATION
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Function Projective Synchronization of Discrete-Time Chaotic and Hyperchaotic Systems Using Backstepping Method
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作者 JIN Yi-Liang LI Kin CHEN Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期111-116,共6页
In this paper, a function projective synchronization scheme is developed to investigate the function projective synchronization between the discrete-time driven chaotic system and the discrete-time response chaotic sy... In this paper, a function projective synchronization scheme is developed to investigate the function projective synchronization between the discrete-time driven chaotic system and the discrete-time response chaotic system. With the aid of symbolic-numeric computation, we use the scheme to study the function projective synchronization between 2D Lorenz discrete-time system and Hdnon discrete-time system, as well as that between 3D discrete-time hyperchaotic system and Henon-like map via three scalar controllers, respectively. Moreover numerical simulations are used to verify the effectiveness of the proposed scheme. 展开更多
关键词 discrete-time chaotic system discrete-time chaotic map symbolic-numeric computation function projective synchronization backstepping design
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