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燃料组件变刚度板弹簧压紧力分析模型研究

核动力工程 2025年第1期46卷 191-198页

作者：金渊彭遥李伟才蔡晓枘张玉相胡海翔中广核研究院有限公司广东深圳518031

为开展压水堆燃料组件变刚度板弹簧的压紧力分析,本文在分析了传统板弹簧加卸载过程的基础上,综合考虑温度变化、辐照生长和辐照松弛等影响因素,进一步分析了变刚度板弹簧在不同加卸载过程中的压紧力变化,给出了变刚度板弹簧的全过程载... 详细信息

为开展压水堆燃料组件变刚度板弹簧的压紧力分析,本文在分析了传统板弹簧加卸载过程的基础上,综合考虑温度变化、辐照生长和辐照松弛等影响因素,进一步分析了变刚度板弹簧在不同加卸载过程中的压紧力变化,给出了变刚度板弹簧的全过程载荷-变形曲线。分析结果表明:燃料组件辐照生长增加了变刚度板弹簧的变形,但不改变加卸载刚度曲线;变刚度板弹簧的辐照松弛过程可分解为2组板弹簧的并联,并分开考虑其辐照松弛量,刚度曲线特性保持不变;当燃料组件辐照生长量大于板弹簧辐照松弛量时,板弹簧的塑性变形将增加。

关键词：燃料组件变刚度板弹簧压紧力

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Adversarial Training-Aided Time-Varying Channel Prediction for TDD/FDD Systems

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China Communications 2023年第6期20卷 100-115页

作者： Zhen zhang yuxiang zhang Jianhua zhang Feifei Gao State Key Lab of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China Institute for Artificial Intelligence Tsinghua UniversityBeijing 100084China

In this paper, a time-varying channel prediction method based on conditional generative adversarial network(CPcGAN) is proposed for time division duplexing/frequency division duplexing(TDD/FDD) systems. CPc GAN utilizes a discriminator to calculate the divergence between the predicted downlink channel state information(CSI) and the real sample distributions under a conditional constraint that is previous uplink CSI. The generator of CPcGAN learns the function relationship between the conditional constraint and the predicted downlink CSI and reduces the divergence between predicted CSI and real *** capability of CPcGAN fitting data distribution can capture the time-varying and multipath characteristics of the channel well. Considering the propagation characteristics of real channel, we further develop a channel prediction error indicator to determine whether the generator reaches the best state. Simulations show that the CPcGAN can obtain higher prediction accuracy and lower system bit error rate than the existing methods under the same user speeds.

关键词： channel prediction time-varying channel conditional generative adversarial network multipath channel deep learning

Subway Embedded Track Geometric Irregularity Safety Limits

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Chinese Journal of Mechanical Engineering 2021年第5期34卷 322-331页

作者： yuxiang zhang Jian Han Huilai Song Yu Liu School of Economics and Management Southwest Jiaotong UniversityChengdu 610031China School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China

A coupling dynamic model of a subway train and an embedded track is established to study the safety limits of track *** simulated vehicle system was a 74-degrees of freedom multi-rigid body model,and the rail was a Timoshenko *** slab was a three-dimensional solid finite element *** sensitive wavelength irregularity was first studied,and then the safety limit of the sensitive wavelength was *** wheel-rail lateral force exhibited a substantial effect on the track alignment and gauge irregularity safety *** wheel-rail vertical force and the rate of wheel load reduction significantly affected the height and cross-level irregularity safety *** results demonstrate that the safety limits of the alignment,gauge,height,and cross-level embedded track geometric irregularity are 5.3 mm,[−10.5,8]mm,5.6 mm,and 6 mm,respectively.

关键词： Embedded track Irregularity Sensitive wavelength Safety limit

Implementation Framework and Validation of Cluster-Nuclei Based Channel Model Using Environmental Mapping for 6G Communication Systems

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China Communications 2022年第4期19卷 1-13页

作者： Li Yu yuxiang zhang Jianhua zhang Zhiqiang Yuan State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

With the research of the upcoming sixth generation(6 G) systems, new technologies will require wider bandwidth, larger scale antenna arrays and more diverse wireless communication scenarios on the future channel modeling. Considering channel model is prerequisite for system design and performance evaluation of 6 G technologies, we face a challenging task: how to accurately and efficiently model 6 G channel for various scenarios? This paper tries to answer it. Firstly, the features of cluster-nuclei(CN) and principle of cluster-nuclei based channel model(CNCM) are introduced. Then, a novel modeling framework is proposed to implement CNCM,which consists four steps: propagation environment reconstruction, cluster-nuclei identification, multipath parameters generation, and channel coefficients generation. Three-dimensional environment with material information is utilized to map CN with scatterers in the propagation pathway. CN are identified by geometrical and electric field calculation based on environmental mapping, and multipath components within CN are calculated by statistical characteristics of angle, power and delay domains. Finally, we present a three-level verification structure to investigate the accuracy and complexity of channel modeling comprehensively. Simulation results reveal that CNCM can perform higher accuracy than geometrybased stochastic model while lower complexity compared with ray-tracing model for practical propagation environment.

关键词： channel model 6G cluster-nuclei environmental mapping scatterer ray-tracing geometrybased stochastic model

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Zabbix校园网监控系统设计与实现

福州大学学报(自然科学版) 2025年第1期53卷 10-16页

作者：郑松奕蒋正亮陈国良张裕祥暨南大学网络与教育技术中心广东广州510632

设计一种基于Zabbix的校园网监控系统,能够对各种异构设备和应用系统进行统一的监控告警,并对收集的各种监控数据进行图形化展示.当监控对象状态超过阈值或触发告警条件时,监控系统能通过邮件、微信、ITSM系统等方式推送告警,方便运维... 详细信息

设计一种基于Zabbix的校园网监控系统,能够对各种异构设备和应用系统进行统一的监控告警,并对收集的各种监控数据进行图形化展示.当监控对象状态超过阈值或触发告警条件时,监控系统能通过邮件、微信、ITSM系统等方式推送告警,方便运维工作人员快速定位故障、排查问题.系统在使用过程中表现良好,对于校园网监控具有较好的参考性.

关键词：校园网 Zabbix 故障自动化处理设计与实现

Prior-guided GAN-based interactive airplane engine damage image augmentation method

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Chinese Journal of Aeronautics 2022年第10期35卷 222-232页

作者： Rui HUANG Bokun DUAN yuxiang zhang Wei FAN School of Computer Science and Technology Civil Aviation University of ChinaTianjin 300300China

Deep learning-based methods have achieved remarkable success in object detection,but this success requires the availability of a large number of training *** sufficient training images is difficult in detecting damages of airplane *** augmenting images by rotation,flipping,and random cropping cannot further improve the generalization ability of existing deep *** propose an interactive augmentation method for airplane engine damage images using a prior-guided GAN to augment training *** method can generate many types of damages on arbitrary image regions according to the strokes of *** proposed model consists of a prior network and a *** Prior network generates a shape prior vector,which is used to encode the information of user *** GAN takes the shape prior vector and random noise vectors to generate candidate *** damages are pasted on the given positions of background images with an improved Poisson *** compare the proposed method with traditional data augmentation methods by training airplane engine damage detectors with state-ofthe-art object detectors,namely,Mask R-CNN,SSD,and YOLO *** results show that training with images generated by our proposed data augmentation method achieves a better detection performance than that by traditional data augmentation methods.

关键词： Airplane engine Damage detection Data augmentation GAN Interactive

Incremental learning of the triangular membership functions based on single-pass FCM and CHC genetic model

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High Technology Letters 2017年第1期23卷 7-15页

作者：霍纬纲 Qu Feng zhang yuxiang Department of Computer Science and Technology Civil Aviation University of ChinaTianjin 300300P.R.China

In order to improve the efficiency of learning the triangular membership functions( TMFs) for mining fuzzy association rule( FAR) in dynamic database,a single-pass fuzzy c means( SPFCM)algorithm is combined with the real-coded CHC genetic model to incrementally learn the TMFs. The cluster centers resulting from SPFCM are regarded as the midpoint of TMFs. The population of CHC is generated randomly according to the cluster center and constraint conditions among TMFs. Then a new population for incremental learning is composed of the excellent chromosomes stored in the first genetic process and the chromosomes generated based on the cluster center adjusted by SPFCM. The experiments on real datasets show that the number of generations converging to the solution of the proposed approach is less than that of the existing batch learning approach. The quality of TMFs generated by the approach is comparable to that of the batch learning approach. Compared with the existing incremental learning strategy,the proposed approach is superior in terms of the quality of TMFs and time cost.

关键词： incremental learning triangular membership function ( TMFs) fuzzy associationrule (FAR) real-coded CHC

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海南岛东部海域拖网网囊网目选择性研究

水产科学 2025年第1期44卷 91-99页

作者：赵海龙刘维吴程宏陈敏张羽翔海南省海洋与渔业科学院海南海口571126

为支撑《全国海洋捕捞准用渔具目录》的实施与管理,2022年4月在海南岛东部海域(E 110°39′~111°12′,N 19°01′~19°33′)采用双支架底拖网渔船联体作业法对网目尺寸分别为25(对照)、30、35、40、45 mm的拖网网囊进行选择性试验,采... 详细信息

为支撑《全国海洋捕捞准用渔具目录》的实施与管理,2022年4月在海南岛东部海域(E 110°39′~111°12′,N 19°01′~19°33′)采用双支架底拖网渔船联体作业法对网目尺寸分别为25(对照)、30、35、40、45 mm的拖网网囊进行选择性试验,采用逻辑斯蒂曲线和极大似然估算法分析拖网网囊网目的选择性。试验结果表明:当网囊网目尺寸为30、35、40、45 mm时,多齿蛇鲻的50%选择体长分别为94.6、104.5、125.0、143.0 mm,选择范围分别为22.2、34.4、23.2、26.1 mm;大头狗母鱼的50%选择体长分别为86.1、96.1、115.2 mm,选择范围分别为29.4、20.0、27.0 mm;六指马鲅的50%选择体长分别为65.9、73.8、89.6、103.1 mm,选择范围分别为9.2、18.0、24.2、21.2 mm;条尾绯鲤的50%选择体长分别为82.6、89.5、100.0 mm,选择范围分别为28.8、26.3、33.5 mm。多齿蛇鲻、大头狗母鱼、六指马鲅和条尾绯鲤的网囊网目尺寸(M_(e))与50%选择体长(L_(50))的线性关系分别为:M_(e)=0.2959L_(50)+2.952(r^(2)=0.9829)、M_(e)=0.3325L_(50)+2.040(r^(2)=0.9685)、M_(e)=0.3861L_(50)+5.403(r^(2)=0.9842)和M_(e)=0.5681L_(50)-16.517(r^(2)=0.9865);多齿蛇鲻、大头狗母鱼、六指马鲅和条尾绯鲤的最小网目尺寸分别为43.9、59.5、58.5、33.2 mm。经综合分析,当前海南岛拖网的适宜网囊网目尺寸应为43.9 mm。

关键词：底拖网联体作业法菱形网目网目尺寸选择性

Latest progress for 3GPP ISAC channel modeling standardization

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Science China(Information Sciences) 2024年第11期67卷 357-358页

作者： yuxiang zhang Jianhua zhang Yuanpeng PEI Yameng LIU Tao JIANG State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Future Research Laboratory China Mobile Research Institute

Integrated sensing and communication(ISAC) is regarded as a promising technology for sixth-generation(6G) *** channel modeling is essential for designing and evaluating the performance of ISAC systems. In December 2023, the 3rd Generation Partnership Project(3GPP)established a new industry specification group dedicated to ISAC. The group's objective is to research ISAC channel modeling, laying the technical foundations for 6G standardization. Compared to the traditional 5G communication channel, 6G ISAC channel requires accurate modeling of new properties.

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