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P4LoF: Scheduling Loop-Free Multi-Flow Updates in Programmable Networks
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作者 Jiqiang Xia Qi Zhan +2 位作者 Le Tian Yuxiang Hu Jianhua Peng 《Computers, Materials & Continua》 2026年第1期1236-1254,共19页
The rapid growth of distributed data-centric applications and AI workloads increases demand for low-latency,high-throughput communication,necessitating frequent and flexible updates to network routing configurations.H... The rapid growth of distributed data-centric applications and AI workloads increases demand for low-latency,high-throughput communication,necessitating frequent and flexible updates to network routing configurations.However,maintaining consistent forwarding states during these updates is challenging,particularly when rerouting multiple flows simultaneously.Existing approaches pay little attention to multi-flow update,where improper update sequences across data plane nodes may construct deadlock dependencies.Moreover,these methods typically involve excessive control-data plane interactions,incurring significant resource overhead and performance degradation.This paper presents P4LoF,an efficient loop-free update approach that enables the controller to reroute multiple flows through minimal interactions.P4LoF first utilizes a greedy-based algorithm to generate the shortest update dependency chain for the single-flow update.These chains are then dynamically merged into a dependency graph and resolved as a Shortest Common Super-sequence(SCS)problem to produce the update sequence of multi-flow update.To address deadlock dependencies in multi-flow updates,P4LoF builds a deadlock-fix forwarding model that leverages the flexible packet processing capabilities of the programmable data plane.Experimental results show that P4LoF reduces control-data plane interactions by at least 32.6%with modest overhead,while effectively guaranteeing loop-free consistency. 展开更多
关键词 network management update consistency programmable data plane P4
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基于Inception-V4与ECA-Net的骨龄自动评估及可视化分析
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作者 张海磊 秦娟 +2 位作者 刘健 李琨 孙桂玲 《电脑知识与技术》 2025年第32期10-13,共4页
针对人工骨龄评估效率低、主观性强的问题,设计了一种基于深度学习的骨龄评估实验系统。该系统首先通过U-Net网络分割手骨区域,并结合局部直方图均衡化与中值滤波进行图像增强与去噪。核心评估模型采用Inception-V4架构,并集成高效通道... 针对人工骨龄评估效率低、主观性强的问题,设计了一种基于深度学习的骨龄评估实验系统。该系统首先通过U-Net网络分割手骨区域,并结合局部直方图均衡化与中值滤波进行图像增强与去噪。核心评估模型采用Inception-V4架构,并集成高效通道注意力(ECA)模块,以增强对关键骨骼发育区域的特征提取能力。为进一步提升模型可解释性,利用Grad-CAM方法生成热力图,以可视化模型决策依据。最终,构建了用户界面以集成评估流程。实验结果表明,该系统能有效提升骨龄评估的准确性,其可解释性为临床医生理解和信任AI决策提供了依据。 展开更多
关键词 骨龄评估 深度学习 inception-v4 注意力机制 可解释人工智能(XAI)
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Research on Predicting the Nephrotoxicity Mechanism of Lianqiao-4 Based on Network Pharmacology and Molecular Docking
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作者 Qingchun Bai Gala Bai Huan Wang 《Journal of Clinical and Nursing Research》 2025年第5期89-99,共11页
Objective:To predict the nephrotoxicity mechanism of Lianqiao-4 through network pharmacology and molecular docking methods.Methods:The main chemical components of Lianqiao(Forsythia suspensa),Bistortae rhizoma,Ophiopo... Objective:To predict the nephrotoxicity mechanism of Lianqiao-4 through network pharmacology and molecular docking methods.Methods:The main chemical components of Lianqiao(Forsythia suspensa),Bistortae rhizoma,Ophiopogonis radix,and Clematidis radix et rhizoma,as well as nephrotoxicity-related targets,were screened through databases such as TCMSP,Swiss Target Prediction,GeneCards,and ETCM.Venny 2.1.0 was used to identify the main components of Lianqiao-4 and nephrotoxicity targets.The STRING platform and David database were utilized to construct a protein-protein interaction(PPI)network diagram,while gene function(GO)enrichment analysis and KEGG pathway analysis were conducted.The“Lianqiao-4 active ingredients-nephrotoxicity targets-signaling pathways”network model was constructed using Cytoscape 3.9.1 software.Results:Network pharmacology and molecular docking analysis revealed that the core active ingredients responsible for the nephrotoxicity mechanism of Mongolian medicine Lianqiao-4 include steroidal saponins such as ophiopogonin A,flavonoids like kaempferol and quercetin,steroidal compounds such asβ-sitosterol and sitosterol,and other key regulatory targets including STAT3,ABCG2,HSP90AA1,MMP9,PTGS2,and EGFR.Major pathways involved include lipid and atherosclerosis,chemical carcinogenesis-DNA adducts,and arachidonic acid metabolism.Conclusion:Mongolian medicine Lianqiao-4 exerts its therapeutic effect on nephrotoxicity through multiple components,targets,and pathways,pending experimental verification. 展开更多
关键词 network pharmacology Molecular docking Lianqiao-4 NEPHROTOXICITY
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一种基于Inception-V4的车位状态检测方法 被引量:1
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作者 王栋 蔡斌斌 宰昶丰 《计算机时代》 2022年第3期5-10,共6页
针对城市停车难,车位检测环境复杂等情况,研究了一种基于Inception-V4算法的车位状态检测方法。在Inception-V4网络结构基础上使用Leaky_ReLU代替ReLU作为激活函数,解决ReLU激活函数引起的神经元失活问题;在网络分类层前添加FReLU激活... 针对城市停车难,车位检测环境复杂等情况,研究了一种基于Inception-V4算法的车位状态检测方法。在Inception-V4网络结构基础上使用Leaky_ReLU代替ReLU作为激活函数,解决ReLU激活函数引起的神经元失活问题;在网络分类层前添加FReLU激活函数层和多个全连接层,使其获得有更丰富语义信息的特征向量,防止了网络过拟合问题,提高车位状态检测模型的整体性能。基于PKLot停车场数据集的实验结果表明,该方法对车位状态检测准确率较原模型有较大程度的提升。 展开更多
关键词 车位检测 深度学习 inception-v4 Leaky_ReLU FReLU
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DPP-4抑制剂治疗的2型糖尿病患者中焦虑和抑郁发生风险的Network meta分析 被引量:6
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作者 王巍巍 高乐 +4 位作者 杨俊 柴三葆 丰雷 武珊珊 孙凤 《中国医刊》 CAS 2018年第9期1044-1049,共6页
目的使用Network meta分析系统评价DPP-4抑制剂类降糖药致2型糖尿病(type 2 diabetes mellitus,T2DM)患者发生焦虑、抑郁的风险。方法系统检索Medline、Embase、Cochrane Library和Clinical Trials.gov网站数据库(截至2016年4月28日)中... 目的使用Network meta分析系统评价DPP-4抑制剂类降糖药致2型糖尿病(type 2 diabetes mellitus,T2DM)患者发生焦虑、抑郁的风险。方法系统检索Medline、Embase、Cochrane Library和Clinical Trials.gov网站数据库(截至2016年4月28日)中比较DPP-4抑制剂与其他降糖药发生焦虑、抑郁风险的随机对照试验(randomized controlled trial,RCT),采用传统meta分析和Network meta分析方法对纳入的RCT研究结果进行合并。结果共纳入44项研究,63 731例T2DM患者,包含9种干预措施:5种DPP-4抑制剂(西格列汀、维格列汀、沙格列汀、利格列汀和阿格列汀)、胰高糖素样肽1受体激动剂、磺脲类、噻唑烷二酮类和安慰剂。传统meta分析结果显示,分别与安慰剂、磺脲类、噻唑烷二酮类相比,DPP-4抑制剂导致焦虑、抑郁发生的风险均较低,但差异无显著性(P>0.05)。Network meta分析发现,与噻唑烷二酮类相比,维格列汀致T2DM患者发生焦虑、抑郁的风险较高,差异有显著性(P<0.05,OR=2.64,95%CI 1.03~6.79),与西格列汀相比,维格列汀致T2DM患者发生焦虑、抑郁的风险较高,差异有显著性(P<0.05,OR=2.42,95%CI 1.00~5.85)。与安慰剂或磺脲类比较,DPP-4抑制剂致T2DM患者发生焦虑、抑郁的风险相当,差异无显著性(P>0.05)。采用基于贝叶斯理论的Network meta分析对9种干预措施进行排序,结果显示西格列汀的风险最低。结论 DPP-4抑制剂不会加重T2DM患者罹患焦虑、抑郁等情绪问题的风险,但不同的DPP-4抑制剂导致的风险程度可能存在差异,建议今后开展的大型前瞻性研究应重视焦虑、抑郁等情绪问题的发生情况,以期为获得更加明确的结论提供证据支持。 展开更多
关键词 DPP-4抑制剂 2型糖尿病 焦虑 抑郁 network META分析
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A network pharmacology study of Sendeng-4,a Mongolian medicine 被引量:12
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作者 ZI Tian YU Dong 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2015年第2期108-118,共11页
We collected the data on the Sendeng-4 chemical composition corresponding targets through the literature and from Drug Bank, SuperT arget, TTD(Therapeutic Targets Database) and other databases and the relevant signali... We collected the data on the Sendeng-4 chemical composition corresponding targets through the literature and from Drug Bank, SuperT arget, TTD(Therapeutic Targets Database) and other databases and the relevant signaling pathways from the KEGG(Kyoto Encyclopedia of Genes and Genomes) database and established models of the chemical composition-target network and chemical composition-target- disease network using Cytoscape software, the analysis indicated that the chemical composition had at least nine different types of targets that acted together to exert effects on the diseases, suggesting a "multi-component, multi-target" feature of the traditional Mongolian medicine. We also employed the rat model of rheumatoid arthritis induced by Collgen Type II to validate the key targets of the chemical components of Sendeng-4, and three of the key targets were validated through laboratory experiments, further confirming the anti-inflammatory effects of Sendeng-4. In all, this study predicted the active ingredients and targets of Sendeng-4, and explored its mechanism of action, which provided new strategies and methods for further research and development of Sendeng-4 and other traditional Mongolian medicines as well. 展开更多
关键词 network pharmacology Mongolian medicine Sendeng-4 Drug targeting Disease pathway networks Rheumatoid arthritis In vivo evaluation
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基于Inception-V4模型的通信信号调制方式识别新方法 被引量:5
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作者 邢科 吕泽均 《现代计算机》 2021年第12期48-54,共7页
针对非合作通信条件下信号调制方式识别问题,提出一种基于Inception-V4模型的通信信号调制方式自动识别新方法。该方法首先将数字信号预处理成星座图,然后将星座图转换成灰度图,最后将灰度图作为神经网络模型的输入,利用Inception-V4网... 针对非合作通信条件下信号调制方式识别问题,提出一种基于Inception-V4模型的通信信号调制方式自动识别新方法。该方法首先将数字信号预处理成星座图,然后将星座图转换成灰度图,最后将灰度图作为神经网络模型的输入,利用Inception-V4网络模型对通信信号的调制方式进行自动识别。Inception-V4模型对信号星座图的形变具有不敏感性,自动学习各种数字调制信号的星座图特征,克服了传统信号调制识别方法中信号特征提取困难,通用性不强,抗噪声性能差等缺点,处理流程简单。仿真实验制作BPSK、4ASK、QPSK、OQPSK、8PSK、16QAM、32QAM、64QAM等8种典型信号的星座图,并选择在信噪比(SNR)为3.5 dB、3 dB、2.5 dB进行调制方式识别试验。在信噪比为2.5 dB时,BPSK、QPSK、4ASK、OQPSK、8PSK的识别准确率依然保持在99.5%以上,实验结果表明,基于Inception-V4模型的通信信号调制方式识别新方法是有效的,且在低信噪比环境下比传统的识别方法有更高的识别准确率。为了评估In-ception-V4模型在信号调制方式识别方面的性能,与AlexNet、InceptionResnetV2-TA模型在调制方式识别的效果进行对比,针对2种典型的调制信号集合进行仿真实验,Inception-V4模型识别准确率较InceptionResnetV2-TA模型提高5%,比AlexNet模型提高12%,进一步表明:将深度学习在图像分类识别领域的模型迁移到通信信号的星座图分类同样适用,对提高非合作通信条件下信号调制方式识别准确率有很大帮助。 展开更多
关键词 调制识别 深度学习 星座图 inception-v4
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基于集成Inception-v4的糖尿病性视网膜病变图像分类 被引量:2
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作者 王宇光 李峰 《软件导刊》 2021年第5期164-167,共4页
糖尿病性视网膜病变严重威胁患者视力,现有的手工分级糖尿病性视网膜病变眼底图像方法费时费力,针对此问题提出一种基于Inception-v4结构的集成网络模型。该模型由5个基于Inception-v4的架构网络集成。通过训练和正则化随机性,即使用相... 糖尿病性视网膜病变严重威胁患者视力,现有的手工分级糖尿病性视网膜病变眼底图像方法费时费力,针对此问题提出一种基于Inception-v4结构的集成网络模型。该模型由5个基于Inception-v4的架构网络集成。通过训练和正则化随机性,即使用相同的训练数据集和ImageNet初始化学习不同的图像特征。在Kaggle-DR数据集上集成Inception-v4网络的AUC值达到0.992;在Messidor-2数据集上集成Inception-v4网络的AUC值达到0.977,灵敏度达到0.923,特异性达到0.947。与在Messidor-2数据集上进行测试的单一网络相比,集成网络表现比单一网络要好,说明集成Inception-v4网络对提高糖尿病性视网膜病变的筛查效率具有一定意义。 展开更多
关键词 inception-v4 糖尿病性视网膜病变 图像分类 迁移学习
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Synthesis,Structure Characterization and Photoluminescence of a Novel Complex with(6,4,4)-Network [Ce_2(2,5-pydc)_3(H_2O)_2](2,5-pydc = Pyridine-2,5-dicarboxylic Acid) 被引量:1
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作者 齐艳娟 毕淑云 苑晓冬 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第9期1421-1425,共5页
A new three-dimensional supramolecular [Ce2(2,5-pydc)3(H2O)2](1) has been hydrothermally synthesized at 180 ℃ and characterized by single-crystal X-ray diffraction.X-ray crystal analyses reveal that the compoun... A new three-dimensional supramolecular [Ce2(2,5-pydc)3(H2O)2](1) has been hydrothermally synthesized at 180 ℃ and characterized by single-crystal X-ray diffraction.X-ray crystal analyses reveal that the compound belongs to the monoclinic system,space group P21/c,C21H13Ce2N3O14,a = 6.561(1),b = 17.986(5),c = 9.411(3) ,β = 95.558(5)° and Z = 2.In the structure of 1,each Ce(1) center is surrounded by 2,5-pydc ligands,forming the 6-connected node,and the 2,5-pydc ligand coordinates to the Ce(Ⅲ) in two different coordination modes.In mode 1,the four oxygen atoms of two carboxyl groups connect neighboring Ce(Ⅲ) ions,giving 4-connected(4-c) second building unit(SBU-1).Furthermore,the structure is extended into a 2-D layer from SBU-1 by sharing Ce(1) atoms.In mode 2,the ligand coordinates to the Ce(Ⅲ) ion from the adjacent chain with the 4-connected(4-c) second building unit(SBU-2),generating a 1-D ladder from SBU-2 by sharing Ce(1) atoms.Finally,the structure is extended into a 6,4,4-c network.Its photoluminescence property was also investigated. 展开更多
关键词 second building unit 6 4 4-c network PHOTOLUMINESCENCE
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Fuzzy Neural Network Model of 4-CBA Concentration for Industrial Purified Terephthalic Acid Oxidation Process 被引量:7
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作者 刘瑞兰 苏宏业 +3 位作者 牟盛静 贾涛 陈渭泉 褚健 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第2期234-239,共6页
A fuzzy neural network (FNN) model is developed to predict the 4-CBA concentration of the oxidation unit in purified terephthalic acid process. Several technologies are used to deal with the process data before modeli... A fuzzy neural network (FNN) model is developed to predict the 4-CBA concentration of the oxidation unit in purified terephthalic acid process. Several technologies are used to deal with the process data before modeling.First,a set of preliminary input variables is selected according to prior knowledge and experience. Secondly,a method based on the maximum correlation coefficient is proposed to detect the dead time between the process variables and response variables. Finally, the fuzzy curve method is used to reduce the unimportant input variables.The simulation results based on industrial data show that the relative error range of the FNN model is narrower than that of the American Oil Company (AMOCO) model. Furthermore, the FNN model can predict the trend of the 4-CBA concentration more accurately. 展开更多
关键词 purified terephthalic acid 4-carboxybenzaldchydc fuzzy neural network soft sensor input variables selection fuzzy curve dead time detection
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Synchronously constructing networked Si_(3)N_(4) nanowires and interconnected graphene inside carbon fiber composites for enhancing mechanical, friction and anti-ablation properties 被引量:3
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作者 Yuming Chen Leilei Zhang +3 位作者 Hongwen Nie Siqi Shao Hongchao Sheng Hejun Li 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第11期167-175,共9页
Carbon fiber(C_(f))reinforced pyrolytic carbon(PyC)composites simultaneously possessing robust mechanical strength,excellent friction performances and outstanding anti-ablation properties are demanded for advanced aer... Carbon fiber(C_(f))reinforced pyrolytic carbon(PyC)composites simultaneously possessing robust mechanical strength,excellent friction performances and outstanding anti-ablation properties are demanded for advanced aerospace applications.Efficient architecture design and optimization of composites are promi-nent yet remain high challenging for realizing the above requirements.Herein,binary reinforcements of networked silicon nitride nanowires(Si_(3)N_(4) nws)and interconnected graphene(GE)have been successfully constructed into C f/PyC by precursor impregnation-pyrolysis and chemical vapor deposition.Notably,net-worked Si_(3)N_(4) nws are uniformly distributed among the carbon fibers,while interconnected GE is firmly rooted on the surface of both networked Si_(3)N_(4) nws and carbon fibers.In the networked Si_(3)N_(4) nws and interconnected GE reinforced C_(f)/PyC,networked Si_(3)N_(4) nws significantly boost the cohesion strength of PyC,while GE markedly improves the interface bonding of both Si_(3)N_(4) nws/PyC and fiber/PyC.Benefiting from the synergistic reinforcement effect of networked Si_(3)N_(4) nws and interconnected GE,the C_(f)/PyC have a prominent enhancement in mechanical(shear and compressive strengths increased by 119.9% and 52.84%,respectively)and friction(friction coefficient and wear rate reduced by 25.40% and 60.10%,respectively)as well as anti-ablation(mass ablation rate and linear ablation rate decreased by 71.25% and 63.01%,respectively).This present strategy for networked Si_(3)N_(4) nws and interconnected GE reinforced C_(f)/PyC provides a dominant route to produce mechanically robust,frictionally resisting and ablatively resistant materials for use in advanced aerospace applications. 展开更多
关键词 networked Si_(3)N_(4)nanowire Interconnected graphene Carbon fiber composite Anti-ablation property
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4-CBA Soft Sensor Based on Fuzzy CMAC Neural Networks 被引量:1
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作者 杜文莉 钱锋 +1 位作者 刘漫丹 张凯 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第3期437-440,共4页
Soft sensor is attractive in dealing with online product quality measurement by virtue of other easily measured variables. In AMOCO PTA (purified terephthalic acid) production process, the unavailability of real-time ... Soft sensor is attractive in dealing with online product quality measurement by virtue of other easily measured variables. In AMOCO PTA (purified terephthalic acid) production process, the unavailability of real-time measurement of 4-CBA makes it impossible for timely adjustment and thereby influences the product quality and the plant economy benefit. In this paper, a kind of FCMAC (fuzzy cerebellar model articulation controller) method is presented to solve the online measurement problem. Different from the conventional CMAC (cerebellar model articulation controller) networks, which has inferior smoothing ability because of its table look-up based technology. Integrating fuzzy model into CMAC networks, it becomes more accurate in functional mapping without weakening its generalization ability. Numerical example and industrial application results show the method proposed here is satisfactory and feasible. 展开更多
关键词 fuzzy CMAC networks 4-carboxybenzaldehyde (4-CBA) purified terephthalic acid plant soft sensor
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Future Mobile Terminal and Network Access Architecture for China 4G Open Mobile Communications 被引量:1
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作者 Willie W.Lu 《China Communications》 SCIE CSCD 2009年第2期134-143,共10页
This paper relates to an advanced open mobile communication system and method of integrating the mobile communications, wireless access systems and wired communications into one common platform architecture for China&... This paper relates to an advanced open mobile communication system and method of integrating the mobile communications, wireless access systems and wired communications into one common platform architecture for China's 4th generation mobile communications, supporting costeffective broadband voice, data and video services in wireless, mobile and wired environment with one single integrated mobile terminal device. The paper includes new architecture in the integrated mobile device and converged network access, and minimum modifi cation in the existing mobile telecommunication infrastructures. This paper introduces the long-term evolution strategy for China's TDD system platform towards China's future 4G mobile communications. 展开更多
关键词 mobile terminal network access architecture 4G mobile communications
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Constitutive modeling of compression behavior of TC4 tube based on modified Arrhenius and artificial neural network models 被引量:5
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作者 Zhi-Jun Tao He Yang +2 位作者 Heng Li Jun Ma Peng-Fei Gao 《Rare Metals》 SCIE EI CAS CSCD 2016年第2期162-171,共10页
Warm rotary draw bending provides a feasible method to form the large-diameter thin-walled(LDTW)TC4 bent tubes, which are widely used in the pneumatic system of aircrafts. An accurate prediction of flow behavior of ... Warm rotary draw bending provides a feasible method to form the large-diameter thin-walled(LDTW)TC4 bent tubes, which are widely used in the pneumatic system of aircrafts. An accurate prediction of flow behavior of TC4 tubes considering the couple effects of temperature,strain rate and strain is critical for understanding the deformation behavior of metals and optimizing the processing parameters in warm rotary draw bending of TC4 tubes. In this study, isothermal compression tests of TC4 tube alloy were performed from 573 to 873 K with an interval of 100 K and strain rates of 0.001, 0.010 and0.100 s^(-1). The prediction of flow behavior was done using two constitutive models, namely modified Arrhenius model and artificial neural network(ANN) model. The predictions of these constitutive models were compared using statistical measures like correlation coefficient(R), average absolute relative error(AARE) and its variation with the deformation parameters(temperature, strain rate and strain). Analysis of statistical measures reveals that the two models show high predicted accuracy in terms of R and AARE. Comparatively speaking, the ANN model presents higher predicted accuracy than the modified Arrhenius model. In addition, the predicted accuracy of ANN model presents high stability at the whole deformation parameter ranges, whereas the predictability of the modified Arrhenius model has some fluctuation at different deformation conditions. It presents higher predicted accuracy at temperatures of 573-773 K, strain rates of 0.010-0.100 s^(-1)and strain of 0.04-0.32, while low accuracy at temperature of 873 K, strain rates of 0.001 s^(-1)and strain of 0.36-0.48.Thus, the application of modified Arrhenius model is limited by its relatively low predicted accuracy at some deformation conditions, while the ANN model presents very high predicted accuracy at all deformation conditions,which can be used to study the compression behavior of TC4 tube at the temperature range of 573-873 K and the strain rate of 0.001-0.100 s^(-1). It can provide guideline for the design of processing parameters in warm rotary draw bending of LDTW TC4 tubes. 展开更多
关键词 TC4 tube Compression behavior Constitutive model Modified Arrhenius model Neural network model
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Super-tough and rapidly self-recoverable multi-bond network hydrogels facilitated by 2-ureido-4[1H]-pyrimidone dimers 被引量:1
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作者 Hao Xu Xu-Ming Xie 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第1期521-524,共4页
Multi-bond network(MBN) hydrogels contain hierarchical dynamic bonds with different bond association energy as energy dissipation units,enabling super-tough mechanical properties.In this work,we copolymerize a protona... Multi-bond network(MBN) hydrogels contain hierarchical dynamic bonds with different bond association energy as energy dissipation units,enabling super-tough mechanical properties.In this work,we copolymerize a protonated 2-ureido-4[1 H]-pyrimidone(UPy)-contained monomer with acrylic acid in HCl solution.After removing excess HCl,UPy motifs are deprotonated and from dimers,thus generating an UPy-contained MBN hydrogel.The obtained MBN hydrogels(75 wt% watercontent) exhibit super-tough mechanical properties(0.39 MPa to 2.51 MPa tensile strength),with tremendous amount of energy(1.68 MJ/m^(3) to 11.1 MJ/m^(3)) dissipated by the dissociation of UPy dimers.The introduction of ionic bonds can further improve the mechanical properties.Moreover,owing to their dynamic nature,both UPy dimers and ionic bonds can re-associate after being dissociated,resulting in excellent self-recovery ability(around 90% recovery efficiency within only 1 h).The excellent self-recovery ability mainly originates from the re-association of UPy dimers based on the high dimerization constant of UPy motifs. 展开更多
关键词 Multi-bond network Quadruple hydrogen bonding SELF-RECOVERY Super-tough hydrogel 2-Ureido-4[1H]-pyrimidone dimer
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Hetero-bimetallic Complex of a 2D Coordination Network Constructed by Sodium Ion and p-Sulfonatothiacalix[4]arene
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作者 郭倩玲 屈一新 马淑兰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第7期767-772,共6页
A 2D coordination polymer built by sodium ion and water-soluble p-sulfonatothiacalix[4]arene of trivalent yttrium complex [Na(H2O)2Y(H2O)6(DMF) (p-sulfonatothiaca lix[4]arene)]-9H2O is reported. The complex be... A 2D coordination polymer built by sodium ion and water-soluble p-sulfonatothiacalix[4]arene of trivalent yttrium complex [Na(H2O)2Y(H2O)6(DMF) (p-sulfonatothiaca lix[4]arene)]-9H2O is reported. The complex belongs to the monoclinic system, space group P2 1/c, with a = 16.703(3), b = 17.819(4), c = 17.357(4)A, β = 106.23(3)°, Z = 4, V = 4960.0(17)A^3, Mr = 1304.08, Dc = 1.746 g/cm^3,μ= 1.624 mm^-1, F(000) = 2688, the final R = 0.0398 and wR = 0.1132 for 7534 observed reflections with I 〉 2σ(I). One yttrium(Ⅲ) ion is coordinated by the thiacalixarene ligand via the sulfonato group, and also ligated by an oxygen atom of a DMF molecule occupying the cavity of thiacalixarene and six aqua ligands. 展开更多
关键词 arene hetero-bimetallic complex 2D coordination network crystal structure
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Simulation and optimization for synthetic technology of 2-chloro-4,6-dinitroresorcinol based on back-propagation neural network
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作者 史瑞欣 Huang Yudong 《High Technology Letters》 EI CAS 2007年第3期283-286,共4页
Back-propagation neural network was applied to predict and optimize the synthetic technology of 2-chloro-4,6-dinitroresorcinol. A model was established based on back-propagation neural network using the experimental d... Back-propagation neural network was applied to predict and optimize the synthetic technology of 2-chloro-4,6-dinitroresorcinol. A model was established based on back-propagation neural network using the experimental data of homogeneous design as the training sample set and the technological parameters were optimized by it. The optimal technological parameters are as follows: the reaction time is 4h, the reaction temperature is 80℃, the molar ratio of NaOH to 4,6-dinitro-1,2,3-trichlorobenzene is 5.5:1, the molar ratio of methanol to 4,6-dinitro-1,2,3- trichlorobenzene is 11:1, and the molar ratio of water to 4,6-dinitro-1,2,3-trichlorobenzene is 70:1. Under the optimal conditions, three groups of experiments were performed and the average yield of 2-chloro-4,6-dinitroresorcinol is 96.64%, the absolute error of it with the predicted value is -1.07%. 展开更多
关键词 2-chlom-4 6-dinitroresorcinol synthetic technology OPTIMIZATION back-propagation neural network model constructing
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Investigation and Technological Comparison of 4G and 5G Networks
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作者 Yunman Hao 《Journal of Computer and Communications》 2021年第1期36-43,共8页
Mobile cellular data networks have allowed users to access the Internet whilst on the move. Many companies use this technology in their products. Examples of this would be Smart Meters in the home and Tesla cars havin... Mobile cellular data networks have allowed users to access the Internet whilst on the move. Many companies use this technology in their products. Examples of this would be Smart Meters in the home and Tesla cars having their “over the air updates”. Both of these two companies use the 4G and 5G technology. So this report will include a technical overview of the technology and protocols (LTE Advanced) used in 4G and 5G networks and how they provide services to the user and how data is transferred within the networks. And there are lots of different parts about the network architecture between the 4G and 5G systems. This report will talk about some different parts between these two systems and some challenges in them. 展开更多
关键词 4G 5G Protocols networkS Mobile Communication
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An Auto-configuration 4M Group Management using Wireless Sensor Networks for Reconfigurable Manufacturing System
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作者 Suk-Keun Cha Jeong-Hoon Lee +4 位作者 Joon Jae Yoo Jung Hoon Kang Han Gyu Kim Dong Hoon Kim Jun Yeob Song 《Journal of Measurement Science and Instrumentation》 CAS 2010年第S1期192-198,共7页
The first tier of automotive manufacturers has faced to pressures about move,modify,updating tasks for manufacturing resources in production processes from demand response of production order sequence for motor compan... The first tier of automotive manufacturers has faced to pressures about move,modify,updating tasks for manufacturing resources in production processes from demand response of production order sequence for motor company and process innovation purpose for productivity. For meets this requirements,it has to require absolutely lead time to re-wiring of physical interface for production equipment,needs for change existing program and test over again.For prepare this constraints,it needs studying an auto-configuration functions that build for both visibility and flexibility based on the 4M(Man,Machine,Material, Method)group management which is supports from WSN (Wireless Sensor Network)of the open embedded device called M2M(Machine to Machine)and major functions of middleware including point manager for real-time device communication,real-time data management,Standard API (Application Program Interface)and application template management.To be application system to RMS (Reconfigurable Manufacturing System)for rapidly response from various orders and model from motor company that is beginning to establishing the mapping of manufacturing resources of 4M using WSN. 展开更多
关键词 Auto-configuration Wireless Sensor network RECONFIGURABLE Production resoureces of 4M TINYOS Machien to Machine MIDDLEWARE Application Template Manager
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Link Budget and Networking Analysis of FuTURE 4G TDD Trial System
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作者 Xu Xiaodong Li Yazhuo Tao Xiaofeng (Wireless Technology Innovation Institute (WTI),Beijing University of Posts and Telecommunications,Beijing 100876,China) 《ZTE Communications》 2007年第3期6-9,共4页
The FuTURE 4G Time Division Duplex (TDD) trial system uses 3.5 GHz carrier frequency and several crucial technologies including broadband Multiple Input Multiple Output (MIMO) and Orthogonal Frequency Division Multipl... The FuTURE 4G Time Division Duplex (TDD) trial system uses 3.5 GHz carrier frequency and several crucial technologies including broadband Multiple Input Multiple Output (MIMO) and Orthogonal Frequency Division Multiplexing (OFDM). These technologies challenge the link budget and networking analysis of the FuTURE 4G TDD trial network. This paper analyzes the practical 3.5 GHz propagation model and the link budget of Radio Frequency (RF) parameters of the trial system. Moreover,it introduces networking analysis and network planning of the trial system,which combines the field test results of the MIMO system. The FuTURE 4G TDD trial system and its trial network have been accomplished with successful checkup. The trial system fulfills all the requirements with two Access Points (AP) and three Mobile Terminals (MT),which supports multi-user,mobility,a high peak rate of 100 Mb/s,High-Definition TV (HDTV),high-speed data download,and Voice over IP (VoIP) services. 展开更多
关键词 TDD Link Budget and networking Analysis of FuTURE 4G TDD Trial System BLER Radio MIMO DBM
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