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HYBRID EXCITATION CLAW-POLE SYNCHRONOUS GENERATOR WITH MAGNETIC CIRCUIT SERIES CONNECTION
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作者 赵朝会 秦海鸿 严仰光 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第1期44-51,共8页
To solve the low efficiency of electric excitation claw-pole synchronous generator(EECPSG) and regulate the magnetic field of permanent magnet (PM) claw-pole synchronous generator(PMCPSG), a novel hybrid excitat... To solve the low efficiency of electric excitation claw-pole synchronous generator(EECPSG) and regulate the magnetic field of permanent magnet (PM) claw-pole synchronous generator(PMCPSG), a novel hybrid excitation claw-pole synchronous generator (HECPSG)with magnetic circuit series connection is proposed. Through the simulation study on the generator using the calculation method for magnetic circuit and 3-D finite element method (FEA), the appropriate magnet thickness and the number of pole-pairs for the proposed generator are determined. Its off-loading characteristics, load characteristics, and regulation behaviors are investigated. The study shows that the appropriate number of pole-pairs in HECPSG with series magnetic circuits is two, and there exists an optimum magnet thickness. Compared to EECPSG, HECPSG realizes dual-directional control to the excitation current. Moreover, the generator can adjust the output voltage and keep the output voltage stable in a broad load range. Under the condition of same parametes, the motor has higer air-gap flux density and power density. 展开更多
关键词 GENERATOR series connection hybrid excitation claw-pole machine
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The Features of Microcontroller EM78P447 and Technique of Port Connection with I^2C Series Bus 被引量:1
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作者 Huang Ji-wu Yang Hong-wei +2 位作者 Li Yang Shen Rui-hua You Zhi 《Wuhan University Journal of Natural Sciences》 CAS 2000年第4期461-463,共3页
By describing the technique of port connection and flow chart ofR/W operation between 24LC01, serial E2PROM, and EM78P447A, features of EM78P447 and its connection with I2C serial bus are introduced. In the end, the p... By describing the technique of port connection and flow chart ofR/W operation between 24LC01, serial E2PROM, and EM78P447A, features of EM78P447 and its connection with I2C serial bus are introduced. In the end, the programe of writing operation is given. 展开更多
关键词 EM78P447A MICROCONTROLLER I2C series bus 24LC01 technique of port connection
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Optimal Culture Capacity of White Shrimp (Litopenaeus vannamei) and Razor Clam (Sinonovacula constricta) in a New Series-Connection Culture Model
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作者 HU Jiabao ZHAO Chunpu +4 位作者 BAO Gege LUO Yunhui WANG Danli XU Jilin XU Shanliang 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第6期1641-1648,共8页
To construct an effective circular mix-culture model and investigate its culture capacity,we established one small and one large systems,with white shrimp(Litopenaeus vannamei)and razor clam(Sinonovacula constricta)cu... To construct an effective circular mix-culture model and investigate its culture capacity,we established one small and one large systems,with white shrimp(Litopenaeus vannamei)and razor clam(Sinonovacula constricta)cultured in separate ponds.The culture water from the L.vannamei was pumped to the S.constricta,and the culture water from the S.constricta overflowed back into the L.vannamei via gravity.In trial I,we tested four culture densities(groups 1–4),and monitored water quality,growth indices,and digestive and immune enzyme activities.From the results,the nitrogen and phosphorus levels generally increased then declined after 56 days,and were lower in groups 1 and 2.The specific growth rate of group 2 was the highest.After 56 days,activities of four digestive enzymes were increased in group 2,and lysozyme activity was significantly decreased in S.constricta in groups 1–4;Alkaline phosphatase activity of L.vannamei was increased in group 3,but decreased in S.constricta in groups 2–4;Acid phosphatase activity was significantly higher in groups 1–3(P<0.05),while SOD and CAT activities were significantly elevated in group 2(P<0.05).Thus,we applied group 2 density for trial II.In trial II,nitrogen and phosphorus concentrations declined significantly during the latter stages,and growth indices were higher than the control(P<0.05).The yields of L.vannamei and S.constricta were significantly higher than the control(P<0.05).The results revealed a good circular mix-culture system with the optimal culture capacity for L.vannamei(40 ind m^(−2))and S.constricta(300 ind m^(−2)),which provided a reference for the future culture of them. 展开更多
关键词 Litopenaeus vannamei Sinonovacula constricta culture capacity series connection culture model water quality
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ON EQUIVALENCE BETWEEN THE SEQUENTIAL CIRCUITS IN SERIES AND IN PARALLEL
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作者 姚天忠 胡铮浩 《苏州大学学报(自然科学版)》 CAS 1990年第2期181-186,共6页
Propose the sequential circuits with the ternary D-ffs in series^1. Discuss the equivalence between the sequential circuits with the p-valued flip-flops in series and in parallel as a part of studying the multiple val... Propose the sequential circuits with the ternary D-ffs in series^1. Discuss the equivalence between the sequential circuits with the p-valued flip-flops in series and in parallel as a part of studying the multiple valued logic circuits. 展开更多
关键词 时序电路 逻辑电路 时序机 有限状态机
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Halin图和Series-Parallel图的动态色数 被引量:1
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作者 董桂香 许振宇 《山东科技大学学报(自然科学版)》 CAS 2005年第1期101-103,共3页
图的动态着色是BruceMontgomery于2001年引入的一个新概念。本文分别证明了Halin图和非5圈的Series Parallel图的动态色数都不超过4。
关键词 HALIN图 seriesparallel 动态着色 动态色数
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Halin图和Series-Parallel图的星荫度 被引量:2
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作者 吴建良 贠军亮 张咏梅 《山东科技大学学报(自然科学版)》 CAS 2000年第4期22-24,共3页
证明了:(1)所有Halin图的星荫度为3,和(2)所有SeriesParallel图的星荫度小于等于3.
关键词 HALIN图 series-parallel 星荫度 染色 星染色
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Selective maintenance problem for series–parallel system under economic dependence 被引量:4
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作者 Qing-zheng XU Le-meng GUO +1 位作者 He-ping SHI Na WANG 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2016年第5期388-400,共13页
In view of the high complexity of the objective world, an economic dependence between subsystems(paired and unpaired) is proposed, and then the maintenance cost and time under different economic dependences are formul... In view of the high complexity of the objective world, an economic dependence between subsystems(paired and unpaired) is proposed, and then the maintenance cost and time under different economic dependences are formulated in a simple and consistent manner. Selective maintenance problem under economic dependence(EDSMP) is presented based on a series–parallel system in this paper. A case study shows that the system reliability is promoted to a certain extent, which can validate the validity of the EDSMP model. The influence of the ratio of set-up cost on system performance is mainly discussed under different economic dependences. Several existing improvements of classical exhaust algorithm are further modified to solve a large sized EDSMP rapidly. Experimental results illustrate that these improvements can reduce CPU time significantly.Furthermore the contribution of each improvement is defined here, and then their contributions are compared thoroughly. 展开更多
关键词 Selective maintenance Economic dependence seriesparallel system Exhaust algorithm
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Performance evaluation of series and parallel strategies for financial time series forecasting 被引量:3
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作者 Mehdi Khashei Zahra Hajirahimi 《Financial Innovation》 2017年第1期357-380,共24页
Background:Improving financial time series forecasting is one of the most challenging and vital issues facing numerous financial analysts and decision makers.Given its direct impact on related decisions,various attemp... Background:Improving financial time series forecasting is one of the most challenging and vital issues facing numerous financial analysts and decision makers.Given its direct impact on related decisions,various attempts have been made to achieve more accurate and reliable forecasting results,of which the combining of individual models remains a widely applied approach.In general,individual models are combined under two main strategies:series and parallel.While it has been proven that these strategies can improve overall forecasting accuracy,the literature on time series forecasting remains vague on the choice of an appropriate strategy to generate a more accurate hybrid model.Methods:Therefore,this study’s key aim is to evaluate the performance of series and parallel strategies to determine a more accurate one.Results:Accordingly,the predictive capabilities of five hybrid models are constructed on the basis of series and parallel strategies compared with each other and with their base models to forecast stock price.To do so,autoregressive integrated moving average(ARIMA)and multilayer perceptrons(MLPs)are used to construct two series hybrid models,ARIMA-MLP and MLP-ARIMA,and three parallel hybrid models,simple average,linear regression,and genetic algorithm models.Conclusion:The empirical forecasting results for two benchmark datasets,that is,the closing of the Shenzhen Integrated Index(SZII)and that of Standard and Poor’s 500(S&P 500),indicate that although all hybrid models perform better than at least one of their individual components,the series combination strategy produces more accurate hybrid models for financial time series forecasting. 展开更多
关键词 series and parallel combination strategies Multilayer perceptrons Autoregressive integrated moving average Financial time series forecasting Stock markets
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Series-parallel图的△-SP算法的实现
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作者 窦明晖 李玲青 黄竞伟 《计算机工程》 CAS CSCD 北大核心 2002年第3期92-93,共2页
讨论了图和它的二叉分解树,对图的△画法进行了详细的描述,给出了该算法的实现过程,并且对图的分解series-parallelS-P-SPS-P树建树算法进行了改进。最后,通过一个具体实例演示了该画法的结果。
关键词 series-parallel 二叉分解树 Δ-SP画法 Δ-SP算法 数据结构
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Integrated parallel forecasting model based on modified fuzzy time series and SVM 被引量:1
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作者 Yong Shuai Tailiang Song Jianping Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第4期766-775,共10页
A dynamic parallel forecasting model is proposed, which is based on the problem of current forecasting models and their combined model. According to the process of the model, the fuzzy C-means clustering algorithm is ... A dynamic parallel forecasting model is proposed, which is based on the problem of current forecasting models and their combined model. According to the process of the model, the fuzzy C-means clustering algorithm is improved in outliers operation and distance in the clusters and among the clusters. Firstly, the input data sets are optimized and their coherence is ensured, the region scale algorithm is modified and non-isometric multi scale region fuzzy time series model is built. At the same time, the particle swarm optimization algorithm about the particle speed, location and inertia weight value is improved, this method is used to optimize the parameters of support vector machine, construct the combined forecast model, build the dynamic parallel forecast model, and calculate the dynamic weight values and regard the product of the weight value and forecast value to be the final forecast values. At last, the example shows the improved forecast model is effective and accurate. 展开更多
关键词 fuzzy C-means clustering fuzzy time series interval partitioning support vector machine particle swarm optimization algorithm parallel forecasting
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A Novel Parallel Scheme for Fast Similarity Search in Large Time Series 被引量:6
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作者 YIN Hong YANG Shuqiang +2 位作者 MA Shaodong LIU Fei CHEN Zhikun 《China Communications》 SCIE CSCD 2015年第2期129-140,共12页
The similarity search is one of the fundamental components in time series data mining,e.g.clustering,classification,association rules mining.Many methods have been proposed to measure the similarity between time serie... The similarity search is one of the fundamental components in time series data mining,e.g.clustering,classification,association rules mining.Many methods have been proposed to measure the similarity between time series,including Euclidean distance,Manhattan distance,and dynamic time warping(DTW).In contrast,DTW has been suggested to allow more robust similarity measure and be able to find the optimal alignment in time series.However,due to its quadratic time and space complexity,DTW is not suitable for large time series datasets.Many improving algorithms have been proposed for DTW search in large databases,such as approximate search or exact indexed search.Unlike the previous modified algorithm,this paper presents a novel parallel scheme for fast similarity search based on DTW,which is called MRDTW(MapRedcuebased DTW).The experimental results show that our approach not only retained the original accuracy as DTW,but also greatly improved the efficiency of similarity measure in large time series. 展开更多
关键词 similarity DTW warping path time series MapReduce parallelization cluster
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Series-parallel Hybrid Vehicle Control Strategy Design and Optimization Using Real-valued Genetic Algorithm 被引量:14
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作者 XIONG Weiwei YIN Chengliang ZHANG Yong ZHANG Jianlong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第6期862-868,共7页
Despite the series-parallel hybrid electric vehicle inherits the performance advantages from both series and parallel hybrid electric vehicle, few researches about the series-parallel hybrid electric vehicle have been... Despite the series-parallel hybrid electric vehicle inherits the performance advantages from both series and parallel hybrid electric vehicle, few researches about the series-parallel hybrid electric vehicle have been revealed because of its complex co nstruction and control strategy. In this paper, a series-parallel hybrid electric bus as well as its control strategy is revealed, and a control parameter optimization approach using the real-valued genetic algorithm is proposed. The optimization objective is to minimize the fuel consumption while sustain the battery state of charge, a tangent penalty function of state of charge(SOC) is embodied in the objective function to recast this multi-objective nonlinear optimization problem as a single linear optimization problem. For this strategy, the vehicle operating mode is switched based on the vehicle speed, and an "optimal line" typed strategy is designed for the parallel control. The optimization parameters include the speed threshold for mode switching, the highest state of charge allowed, the lowest state of charge allowed and the scale factor of the engine optimal torque to the engine maximum torque at a rotational speed. They are optimized through numerical experiments based on real-value genes, arithmetic crossover and mutation operators. The hybrid bus has been evaluated at the Chinese Transit Bus City Driving Cycle via road test, in which a control area network-based monitor system was used to trace the driving schedule. The test result shows that this approach is feasible for the control parameter optimization. This approach can be applied to not only the novel construction presented in this paper, but also other types of hybrid electric vehicles. 展开更多
关键词 series-parallel hybrid electric vehicle control strategy DESIGN OPTIMIZATION real-valued genetic algorithm
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Parallel Molecular Dynamics on the Connection Machines 被引量:1
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作者 Daniel I. Okunbor 《Wuhan University Journal of Natural Sciences》 CAS 1996年第Z1期337-343,共7页
Abstract Abstract:We have demonstrated using vectorized parallel Lennard-Jones fluid program that vectorizing general-purpose parallel molecular package for simulating biomolecules which currently runs on the Connect... Abstract Abstract:We have demonstrated using vectorized parallel Lennard-Jones fluid program that vectorizing general-purpose parallel molecular package for simulating biomolecules which currently runs on the Connection Machine CM-5 using CMMD message passing would offer a significant improvement over 4 non-vectorized version. Our results indicate that the Lennard-Jones fluid program written in C*/CMNID is five times faster than the same program written in C/CMMD. 展开更多
关键词 parallel Molecular Dynamics on the connection Machines
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Series-Parallel图的全选择数与全色数
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作者 李涛 《河南大学学报(自然科学版)》 CAS 2001年第4期37-40,共4页
对 2_连通Series_Parallel图G ,证明了当Δ(G) 4时 ,其全选择数等于Δ(G) +1;在Δ(G) 3时 ,其全色数等于Δ(G) +1;对Δ(G)≠ 3时 ,其边选择数等于其边色数 (即列表染色猜想 ) .由于外平面图是特殊的Series_Parallel图 。
关键词 series-parallel 平面图 全染色 全选择数 全色数
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Design and Strategy of Series-Parallel Hybrid System Based on BSFC 被引量:2
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作者 Huien Gao Liang Chu +1 位作者 Jianhua Guo Dianbo Zhang 《Journal of Beijing Institute of Technology》 EI CAS 2018年第4期564-574,共11页
In this paper,a drive control strategy is developed based on the characteristics of series-parallel plug-in hybrid system.Energy management strategies in various modes are established with the basis on the minimum bra... In this paper,a drive control strategy is developed based on the characteristics of series-parallel plug-in hybrid system.Energy management strategies in various modes are established with the basis on the minimum brake specific fuel consumption(BSFC)curve of engine.The control strategy,which is based on rules and system efficiency,is adopted to determine the entry/exit mechanisms of various modes according to battery state of charge(SOC),required power and required speed.The vehicle test results verify that the proposed control strategy can improve vehicle economy efficiently and makes a good effect on engine control. 展开更多
关键词 series-parallel plug-in hybrid electric vehicle(PHEV) based on rules based on system efficiency
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Series-Parallel图上最小权顶点覆盖3-路问题的有效算法
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作者 张文杰 涂建华 《北京化工大学学报(自然科学版)》 CAS CSCD 北大核心 2019年第1期124-128,共5页
研究了Series-Parallel图上的顶点覆盖3-路问题,利用动态规划思想,给出一个能在多项式时间内完成的有效算法,该算法的运行时间为O(|V|)。
关键词 series-parallel 顶点覆盖k-路问题 有效算法 动态规划
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Existence and Uniqueness of the Dynamic Solution of a Series-Parallel Repairable System Consisting of Three-Unit with Multiple Vacations of a Repairman 被引量:2
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作者 Abdukerim Haji Tursunjan Keyim Bilikiz Yunus 《Journal of Applied Mathematics and Physics》 2016年第8期1585-1591,共7页
We investigate a series-parallel repairable system consisting of three-unit with multiple vacations of a repairman. By using C0-semigroup theory of linear operators in the functional analysis, we prove that the system... We investigate a series-parallel repairable system consisting of three-unit with multiple vacations of a repairman. By using C0-semigroup theory of linear operators in the functional analysis, we prove that the system is well-posed and has a unique positive dynamic solution. 展开更多
关键词 series-parallel Repairable System C_0-Semigroup Dynamic Solution
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Input series out putparallel based multi-modular boost half bridge DC-DC converter with a dynamic control scheme
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作者 SOOMRO Amir Mahmood SYED Amjad Ali +2 位作者 KHIZER Arbab Nighat 廖晓钟 MANZOOR Muhammad Farhan 《Journal of Beijing Institute of Technology》 EI CAS 2014年第4期519-526,共8页
Multi-modular system plays an important role in power system architecture because low voltage and low power converters can be connected in any combination parallel or series at input/ output side in order to obtained ... Multi-modular system plays an important role in power system architecture because low voltage and low power converters can be connected in any combination parallel or series at input/ output side in order to obtained any given power system specifications. Multi-modular boost haft bridge DC-DC converter in the configuration of input series output parallel has been investigated in this paper. The boost half bridge DC-DC converters are connected in input series output parallel con- figuration in order to achieve equal input voltage sharing and output current sharing between the con- verters. This can be achieved with the help of dynamic control scheme which consists of two loops, a voltage loop and a current loop, for each module. Dynamic behavior of multi-modular converter configuration has been observe by varying the load condition. Moreover, the results obtained through multi-modular converter describe that the system has good dynamic and steady state response. Al- though two converter modules are focused in this paper but it can be modified to any number of modules. 展开更多
关键词 boost haft bridge BHB input series output parallel ISOP input voltage sharing(IVS) multi-modular output current sharing (OCS)
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Modeling and character analyzing of multiple fractional-order memcapacitors in parallel connection
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作者 Xiang Xu Gangquan Si +1 位作者 Zhang Guo Babajide Oluwatosin Oresanya 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期642-651,共10页
Recently,the memory elements-based circuits have been addressed frequently in the nonlinear circuit theory due to their unique behaviors.Thus,the modeling and characterizing of the mem-elements become essential.In thi... Recently,the memory elements-based circuits have been addressed frequently in the nonlinear circuit theory due to their unique behaviors.Thus,the modeling and characterizing of the mem-elements become essential.In this paper,the analysis of the multiple fractional-order voltage-controlled memcapacitors model in parallel connection is studied.Firstly,two fractional-order memcapacitors are connected in parallel,the equivalent model is derived,and the characteristic of the equivalent memcapacitor is analyzed in positive or negative connection.Then a new understanding manner according to different rate factor K and fractional orderαis derived to explain the equivalent modeling structure conveniently.Additionally,the negative order appears,which is a consequence of the combination of memcapacitors in different directions.Meanwhile,the equivalent parallel memcapacitance has been drawn to determine that multiple fractional-order memcapacitors could be calculated as one composite memcapacitor.Thus,an arbitrary fractional-order equivalent memcapacitor could be constructed by multiple fractional-order memcapacitors. 展开更多
关键词 memcapacitor fractional calculus parallel connection equivalent model
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Load Dependent Series-Parallel Systems with Common Bus Performance Sharing Mechanism 被引量:1
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作者 肖辉 彭锐 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期770-773,共4页
A series-parallel system was proposed with common bus performance sharing in which the performance and failure rate of the element depended on the load it was carrying. In such a system,the surplus performance of a su... A series-parallel system was proposed with common bus performance sharing in which the performance and failure rate of the element depended on the load it was carrying. In such a system,the surplus performance of a sub-system can be transmitted to other deficient sub-systems. The transmission capacity of the common bus performance sharing mechanism is a random variable. Effects of load on element performance and failure rate were considered in this paper. A reliability evaluation algorithm based on the universal generating function technique was suggested. Numerical experiments were conducted to illustrate the algorithm. 展开更多
关键词 multi-state reliability series-parallel system load dependent failure rate common bus performance sharing
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