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Generation of SARS-CoV-2 dual-target candidate inhibitors through 3D equivariant conditional generative neural networks 被引量:1
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作者 Zhong-Xing Zhou Hong-Xing Zhang Qingchuan Zheng 《Journal of Pharmaceutical Analysis》 2025年第6期1291-1310,共20页
Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)mutations are influenced by random and uncontrollable factors,and the risk of the next widespread epidemic remains.Dual-target drugs that synergistically act ... Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)mutations are influenced by random and uncontrollable factors,and the risk of the next widespread epidemic remains.Dual-target drugs that synergistically act on two targets exhibit strong therapeutic effects and advantages against mutations.In this study,a novel computational workflow was developed to design dual-target SARS-CoV-2 candidate inhibitors with the Envelope protein and Main protease selected as the two target proteins.The drug-like molecules of our self-constructed 3D scaffold database were used as high-throughput molecular docking probes for feature extraction of two target protein pockets.A multi-layer perceptron(MLP)was employed to embed the binding affinities into a latent space as conditional vectors to control conditional distribution.Utilizing a conditional generative neural network,cG-SchNet,with 3D Euclidean group(E3)symmetries,the conditional probability distributions of molecular 3D structures were acquired and a set of novel SARS-CoV-2 dual-target candidate inhibitors were generated.The 1D probability,2D joint probability,and 2D cumulative probability distribution results indicate that the generated sets are significantly enhanced compared to the training set in the high binding affinity area.Among the 201 generated molecules,42 molecules exhibited a sum binding affinity exceeding 17.0 kcal/mol while 9 of them having a sum binding affinity exceeding 19.0 kcal/mol,demonstrating structure diversity along with strong dual-target affinities,good absorption,distribution,metabolism,excretion,and toxicity(ADMET)properties,and ease of synthesis.Dual-target drugs are rare and difficult to find,and our“high-throughput docking-multi-conditional generation”workflow offers a wide range of options for designing or optimizing potent dual-target SARS-CoV-2 inhibitors. 展开更多
关键词 SARS-CoV-2 Dual-target drug 3D generative neural networks Drug design
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3D tomographic analysis of equatorial plasma bubble using GNSS-TEC data from Indonesian GNSS Network
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作者 Ihsan Naufal Muafiry Prayitno Abadi +5 位作者 Teguh N.Pratama Dyah R.Martiningrum Sri Ekawati Yuandhika GWismaya Febrylian FChabibi Gatot HPramono 《Earth and Planetary Physics》 EI CAS 2025年第1期127-136,共10页
Equatorial Plasma Bubbles(EPBs)are ionospheric irregularities that take place near the magnetic equator.EPBs most commonly occur after sunset during the equinox months,although they can also be observed during other s... Equatorial Plasma Bubbles(EPBs)are ionospheric irregularities that take place near the magnetic equator.EPBs most commonly occur after sunset during the equinox months,although they can also be observed during other seasons.The phenomenon significantly disrupts radio wave signals essential to communication and navigation systems.The national network of Global Navigation Satellite System(GNSS)receivers in Indonesia(>30°longitudinal range)provides an opportunity for detailed EPB studies.To explore this,we conducted preliminary 3D tomography of total electron content(TEC)data captured by GNSS receivers following a geomagnetic storm on December 3,2023,when at least four EPB clusters occurred in the Southeast Asian sector.TEC and extracted TEC depletion with a 120-minute running average were then used as inputs for a 3D tomography program.Their 2D spatial distribution consistently captured the four EPB clusters over time.These tomography results were validated through a classical checkerboard test and comparisons with other ionospheric data sources,such as the Global Ionospheric Map(GIM)and International Reference Ionosphere(IRI)profile.Validation of the results demonstrates the capability of the Indonesian GNSS network to measure peak ionospheric density.These findings highlight the potential for future three-dimensional research of plasma bubbles in low-latitude regions using existing GNSS networks,with extensive longitudinal coverage. 展开更多
关键词 EPB Indonesian GNSS network 3D tomography
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Modeling and Comprehensive Review of Signaling Storms in 3GPP-Based Mobile Broadband Networks:Causes,Solutions,and Countermeasures
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作者 Muhammad Qasim Khan Fazal Malik +1 位作者 Fahad Alturise Noor Rahman 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期123-153,共31页
Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important a... Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important and scarce network resources such as bandwidth and processing power.There have been several reports of these control signaling turning into signaling storms halting network operations and causing the respective Telecom companies big financial losses.This paper draws its motivation from such real network disaster incidents attributed to signaling storms.In this paper,we present a thorough survey of the causes,of the signaling storm problems in 3GPP-based mobile broadband networks and discuss in detail their possible solutions and countermeasures.We provide relevant analytical models to help quantify the effect of the potential causes and benefits of their corresponding solutions.Another important contribution of this paper is the comparison of the possible causes and solutions/countermeasures,concerning their effect on several important network aspects such as architecture,additional signaling,fidelity,etc.,in the form of a table.This paper presents an update and an extension of our earlier conference publication.To our knowledge,no similar survey study exists on the subject. 展开更多
关键词 Signaling storm problems control signaling load analytical modeling 3GPP networks smart devices diameter signaling mobile broadband data access data traffic mobility management signaling network architecture 5G mobile communication
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3D bioprinted unidirectional neural network and its application for alcoholic neurodegeneration
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作者 Mihyeon Bae Joeng Ju Kim +1 位作者 Jinah Jang Dong-Woo Cho 《International Journal of Extreme Manufacturing》 2025年第5期294-312,共19页
The brain exhibits complex physiology characterized by unique features such as a brain-specific extracellular matrix, compartmentalized structure (white and grey matter), and an aligned axonal network. These physiolog... The brain exhibits complex physiology characterized by unique features such as a brain-specific extracellular matrix, compartmentalized structure (white and grey matter), and an aligned axonal network. These physiological characteristics underpin brain function and facilitate signal transduction similar to that in an electrical circuit. Therefore, investigating these features in vitro is crucial for understanding the interactions between neuronal signal transduction processes and the pathology of neurological diseases. Compared to neurons on patterned substrates, three-dimensional (3D) bioprinting-based neural models provide significant advantages in replicating axonal kinetics without physical limitations. This study proposes the development of a 3D bioprinted engineered neural network (BENN) model to replicate the physiological features of the brain, suggesting its application as a tool for studying neurodegenerative diseases. We employed 3D bioprinting to reconstruct the compartmentalized structure of the brain, and controlled the directionality of axonal growth by applying electrical stimuli to the printed neural structure for overcoming spatial constraints. The reconstructed axonal network demonstrated reliability as a neural analog, including the visualization of mature neuronal features and spontaneous calcium reactions. Furthermore, these brain-like neural network models have demonstrated usefulness for studying neurodegeneration by enabling the visualization of degenerative pathophysiology in alcohol-exposed neurons. The BENN facilitates the visualization of region-specific pathological markers in soma or axon populations, including amyloid-beta formation and axonal deformation. Overall, the BENN closely mimics brain physiology, offers insights into the dynamics of axonal networks, and can be applied to studying neurological diseases. 展开更多
关键词 3D bioprinting engineered neural network NEURODEGENERATION
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Fusion Prototypical Network for 3D Scene Graph Prediction
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作者 Jiho Bae Bogyu Choi +1 位作者 Sumin Yeon Suwon Lee 《Computer Modeling in Engineering & Sciences》 2025年第6期2991-3003,共13页
Scene graph prediction has emerged as a critical task in computer vision,focusing on transforming complex visual scenes into structured representations by identifying objects,their attributes,and the relationships amo... Scene graph prediction has emerged as a critical task in computer vision,focusing on transforming complex visual scenes into structured representations by identifying objects,their attributes,and the relationships among them.Extending this to 3D semantic scene graph(3DSSG)prediction introduces an additional layer of complexity because it requires the processing of point-cloud data to accurately capture the spatial and volumetric characteristics of a scene.A significant challenge in 3DSSG is the long-tailed distribution of object and relationship labels,causing certain classes to be severely underrepresented and suboptimal performance in these rare categories.To address this,we proposed a fusion prototypical network(FPN),which combines the strengths of conventional neural networks for 3DSSG with a Prototypical Network.The former are known for their ability to handle complex scene graph predictions while the latter excels in few-shot learning scenarios.By leveraging this fusion,our approach enhances the overall prediction accuracy and substantially improves the handling of underrepresented labels.Through extensive experiments using the 3DSSG dataset,we demonstrated that the FPN achieves state-of-the-art performance in 3D scene graph prediction as a single model and effectively mitigates the impact of the long-tailed distribution,providing a more balanced and comprehensive understanding of complex 3D environments. 展开更多
关键词 3D scene graph prediction prototypical network 3D scene understanding
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Effectiveness of Invertible Neural Network in Variable Material 3D Printing:Application to Screw-Based Material Extrusion
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作者 Yunze Wang Beining Zhang +5 位作者 Siwei Lu Chuncheng Yang Ling Wang Jiankang He Changning Sun Dichen Li 《Additive Manufacturing Frontiers》 2025年第2期20-29,共10页
Variable material screw-based material extrusion(S-MEX)3D printing technology provides a novel approach for fabricating composites with continuous material gradients.Nevertheless,achieving precise alignment between th... Variable material screw-based material extrusion(S-MEX)3D printing technology provides a novel approach for fabricating composites with continuous material gradients.Nevertheless,achieving precise alignment between the process parameters and material compositions is challenging because of fluctuations in the melt rheological state caused by material variations.In this study,an invertible extrusion prediction model for 0-40 wt% short carbon fiber reinforced polyether-ether-ketone(SCF/PEEK)in the S-MEX process was established using an invertible neural network(INN)that demonstrated the capabilities of forward flow rate prediction and inverse process optimization with accuracies of 0.852 and 0.877,respectively.Moreover,a strategy for adjusting the screw speeds using process parameters obtained from the INN was developed to maintain a consistent flow rate during the variable material printing process.Benefiting from uniform flow,the linewidth accuracy was improved by 77%,and the surface roughness was reduced by 51%.Adjusting the process parameters by using an INN offers significant potential for flow rate control and the enhancement of the overall performance of variable material 3D printing. 展开更多
关键词 Material extrusion 3D printing Multi-material Invertible neural network
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Prediction of Quality Markers(Q-Markers)for the Mongolian Medicine Naru-3 Based on Chemical Composition,Pharmacological Effects,and Network Pharmacology
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作者 Ying En Liang Xu Jiaqi Yu 《Journal of Clinical and Nursing Research》 2025年第1期1-10,共10页
Naru Sanwei Pill,also known as Naru-3,a Mongolian medicine originating from Zhigao Pharmacopoeia,is a classic prescription used in the treatment of rheumatism.It is composed of Terminalia chebula,processed Aconitum ku... Naru Sanwei Pill,also known as Naru-3,a Mongolian medicine originating from Zhigao Pharmacopoeia,is a classic prescription used in the treatment of rheumatism.It is composed of Terminalia chebula,processed Aconitum kusnezoffii Reichb.,and Piper longum,and is known for its effects in eliminating“mucus,”relieving pain,and reducing swelling,with significant efficacy in treating joint effusion and lumbar pain.In recent years,researchers have summarized its chemical components and pharmacological effects,and employed network pharmacology methods based on the core theory of Traditional Chinese Medicine quality markers(Q-Markers)to analyze and predict its markers.The results identified potential Q-Markers for Naru-3,providing a scientific basis for quality control and further research. 展开更多
关键词 Mongolian medicine Naru-3 network pharmacology Quality markers Chemical components Pharmacological effects
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A lignin-based polyelectrolyte with fast 3D Li^(+)transportation network
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作者 Pengfei Sun Yeqiang Zhang +4 位作者 Chengdong Fang Jinji Lan Yanping Chen Liubin Feng Jiajia Chen 《Journal of Energy Chemistry》 2025年第8期114-121,共8页
In this work,we have developed a lignin-derived polymer electrolyte(LSELi),which demonstrates exceptional ionic conductivity of 1.6×10^(-3)S cm^(−1)and a high cation transference number of 0.57 at 25°C.Time ... In this work,we have developed a lignin-derived polymer electrolyte(LSELi),which demonstrates exceptional ionic conductivity of 1.6×10^(-3)S cm^(−1)and a high cation transference number of 0.57 at 25°C.Time of flight secondary ion mass spectrometry(TOF-SIMS)analysis shows that the large-size 1-ethyl-3-methylimidazolium cations(EMIM^(+))can induce the aggregation of the anionic segments in lignosulfonate to reconstruct the three-dimensional(3D)spatial structure of polyelectrolyte,thereby forming a fluent Li^(+)transport 3D network.Dielectric loss spectroscopy further reveals that within this transport network,Li^(+)transport is decoupled from the relaxation of lignosulfonate chain segments,exhibiting characteristics of rapid Li^(+)transport.Furthermore,in-situ distribution of relaxation times analysis indicates that a stable solid electrolyte interface layer is formed at the Li plating interface with LSELi,optimizing the Li plating interface and exhibiting low charge transfer impedance and stable Li plating and stripping.Thus,a substantially prolonged cycling stability and reversibility are obtained in the Li||LSELi||Li battery at 25°C(1800 h at 0.1 mA cm^(−2),0.1 mAh cm^(−2)).At 25°C,the Li||LSELi||LiFePO_(4)cell shows 132 mAh g^(−1)of capacity with 92.7%of retention over 120 cycles at 0.1 mA cm^(−2). 展开更多
关键词 Lithium metal batteries Lignin-based polyelectrolyte 3D Li^(+)transportation network Rechargeable batteries
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Adaptive Fusion Neural Networks for Sparse-Angle X-Ray 3D Reconstruction
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作者 Shaoyong Hong Bo Yang +4 位作者 Yan Chen Hao Quan Shan Liu Minyi Tang Jiawei Tian 《Computer Modeling in Engineering & Sciences》 2025年第7期1091-1112,共22页
3D medical image reconstruction has significantly enhanced diagnostic accuracy,yet the reliance on densely sampled projection data remains a major limitation in clinical practice.Sparse-angle X-ray imaging,though safe... 3D medical image reconstruction has significantly enhanced diagnostic accuracy,yet the reliance on densely sampled projection data remains a major limitation in clinical practice.Sparse-angle X-ray imaging,though safer and faster,poses challenges for accurate volumetric reconstruction due to limited spatial information.This study proposes a 3D reconstruction neural network based on adaptive weight fusion(AdapFusionNet)to achieve high-quality 3D medical image reconstruction from sparse-angle X-ray images.To address the issue of spatial inconsistency in multi-angle image reconstruction,an innovative adaptive fusion module was designed to score initial reconstruction results during the inference stage and perform weighted fusion,thereby improving the final reconstruction quality.The reconstruction network is built on an autoencoder(AE)framework and uses orthogonal-angle X-ray images(frontal and lateral projections)as inputs.The encoder extracts 2D features,which the decoder maps into 3D space.This study utilizes a lung CT dataset to obtain complete three-dimensional volumetric data,from which digitally reconstructed radiographs(DRR)are generated at various angles to simulate X-ray images.Since real-world clinical X-ray images rarely come with perfectly corresponding 3D“ground truth,”using CT scans as the three-dimensional reference effectively supports the training and evaluation of deep networks for sparse-angle X-ray 3D reconstruction.Experiments conducted on the LIDC-IDRI dataset with simulated X-ray images(DRR images)as training data demonstrate the superior performance of AdapFusionNet compared to other fusion methods.Quantitative results show that AdapFusionNet achieves SSIM,PSNR,and MAE values of 0.332,13.404,and 0.163,respectively,outperforming other methods(SingleViewNet:0.289,12.363,0.182;AvgFusionNet:0.306,13.384,0.159).Qualitative analysis further confirms that AdapFusionNet significantly enhances the reconstruction of lung and chest contours while effectively reducing noise during the reconstruction process.The findings demonstrate that AdapFusionNet offers significant advantages in 3D reconstruction of sparse-angle X-ray images. 展开更多
关键词 3D reconstruction adaptive fusion X-ray imaging medical imaging deep learning neural networks sparse angles autoencoder
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Polymerized-ionic-liquid-based solid polymer electrolyte for ultra-stable lithium metal batteries enabled by structural design of monomer and crosslinked 3D network
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作者 Lingwang Liu Jiangyan Xue +14 位作者 Yiwen Gao Shiqi Zhang Haiyang Zhang Keyang Peng Xin Zhang Suwan Lu Shixiao Weng Haifeng Tu Yang Liu Zhicheng Wang Fengrui Zhang Daosong Fu Jingjing Xu Qun Luo Xiaodong Wu 《Materials Reports(Energy)》 2025年第1期61-69,共9页
Solid polymer electrolytes(SPEs)have attracted much attention for their safety,ease of packaging,costeffectiveness,excellent flexibility and stability.Poly-dioxolane(PDOL)is one of the most promising matrix materials ... Solid polymer electrolytes(SPEs)have attracted much attention for their safety,ease of packaging,costeffectiveness,excellent flexibility and stability.Poly-dioxolane(PDOL)is one of the most promising matrix materials of SPEs due to its remarkable compatibility with lithium metal anodes(LMAs)and suitability for in-situ polymerization.However,poor thermal stability,insufficient ionic conductivity and narrow electrochemical stability window(ESW)hinder its further application in lithium metal batteries(LMBs).To ameliorate these problems,we have successfully synthesized a polymerized-ionic-liquid(PIL)monomer named DIMTFSI by modifying DOL with imidazolium cation coupled with TFSI^(-)anion,which simultaneously inherits the lipophilicity of DOL,high ionic conductivity of imidazole,and excellent stability of PILs.Then the tridentate crosslinker trimethylolpropane tris[3-(2-methyl-1-aziridine)propionate](TTMAP)was introduced to regulate the excessive Li^(+)-O coordination and prepare a flame-retardant SPE(DT-SPE)with prominent thermal stability,wide ESW,high ionic conductivity and abundant Lit transference numbers(t_(Li+)).As a result,the LiFePO_(4)|DT-SPE|Li cell exhibits a high initial discharge specific capacity of 149.60 mAh g^(-1)at 0.2C and 30℃with a capacity retention rate of 98.68%after 500 cycles.This work provides new insights into the structural design of PIL-based electrolytes for long-cycling LMBs with high safety and stability. 展开更多
关键词 Polymerized ionic liquid Solid polymer electrolyte Structural design Crosslinked 3D network Lithium metal battery
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Actuator Fault Diagnosis of 3-PR(P)S Parallel Robot Based on Dung Beetle Optimization-Back Propagation Neural Network
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作者 Junjie Huang Chenhao Huangfu +3 位作者 Qinlei Zhang Shikai Li Yonggang Yan Jiangkun Cai 《Journal of Dynamics, Monitoring and Diagnostics》 2025年第2期91-100,共10页
Any malfunctions of the actuators of the robots have the potential to destroy the robot’s normal motion,and most of the current actuator fault diagnosis methods are difficult to meet the requirements of simplifying t... Any malfunctions of the actuators of the robots have the potential to destroy the robot’s normal motion,and most of the current actuator fault diagnosis methods are difficult to meet the requirements of simplifying the actuator modeling and solving the difficulty of fault data collection.To solve the problem of real-time diagnosis of actuator faults in the 3-PR(P)S parallel robot,the model of 3-PR(P)S parallel robot and data-driven-based method for the fault diagnosis are presented.Firstly,only the input-output relationship of the actuator is considered for modeling actuator faults,reducing the complexity of fault modeling and reducing the time consumption of parameter identification,thereby meeting the requirements of real-time diagnosis.A Simulink model of the electromechanical actuator(EMA)was constructed to analyze actuator faults.Then the short-term analysis method was employed for collecting the sample data of the slider position on the test platform of the EMA system and feature extraction.Training samples for neural networks are obtained.Furthermore,we optimized the Back Propagation(BP)neural network using the Dung Beetle Optimization Algorithm(DBO),which effectively resolved the weights and thresholds of the BP neural network.Compared to BP and Particle Swarm Optimization(PSO)-BP,the DBO-BP has better convergence,convergence rate,and the best-classifying quality.So,the classification for the different actuator faults is obviously improved.Finally,a fault diagnosis system was designed for the actuator of the 3-PR(P)S parallel robot,and the experimental results demonstrate that this system can detect actuator faults within 0.1 seconds.This work also provides the technical support for the fault-tolerant control of the 3-PR(P)S Parallel robot. 展开更多
关键词 ACTUATOR Back Propagation neural network Dung Beetle Algorithm fault diagnosis 3-PR(P)S parallel robot
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Alloy gene Gibbs energy partition function and equilibrium holographic network phase diagrams of AuCu_3-type sublattice system 被引量:3
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作者 谢佑卿 李小波 +2 位作者 刘心笔 聂耀庄 彭红建 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3585-3610,共26页
Taking AuCu3-type sublattice system as an example, three discoveries have been presented: First, the third barrier hindering the progress in metal materials science is that researchers have got used to recognizing exp... Taking AuCu3-type sublattice system as an example, three discoveries have been presented: First, the third barrier hindering the progress in metal materials science is that researchers have got used to recognizing experimental phenomena of alloy phase transitions during extremely slow variation in temperature by equilibrium thinking mode and then taking erroneous knowledge of experimental phenomena as selected information for establishing Gibbs energy function and so-called equilibrium phase diagram. Second, the equilibrium holographic network phase diagrams of AuCu3-type sublattice system may be used to describe systematic correlativity of the composition?temperature-dependent alloy gene arranging structures and complete thermodynamic properties, and to be a standard for studying experimental subequilibrium order-disorder transition. Third, the equilibrium transition of each alloy is a homogeneous single-phase rather than a heterogeneous two-phase, and there exists a single-phase boundary curve without two-phase region of the ordered and disordered phases; the composition and temperature of the top point on the phase-boundary curve are far away from the ones of the critical point of the AuCu3 compound. 展开更多
关键词 AuCu3 compound AuCu3-type sublattice system alloy gene Gibbs energy partition function equilibrium holographic network phase diagram systematic metal materials science
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Alloy gene Gibbs energy partition function and equilibrium holographic network phase diagrams of Au_3Cu-type sublattice system 被引量:3
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作者 谢佑卿 聂耀庄 +2 位作者 李小波 彭红建 刘心笔 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第1期211-240,共30页
Taking Au3Cu-type sublattice system as an example, three discoveries have been presented. First, the fourth barrier to hinder the progress of metal materials science is that today’s researchers do not understand that... Taking Au3Cu-type sublattice system as an example, three discoveries have been presented. First, the fourth barrier to hinder the progress of metal materials science is that today’s researchers do not understand that the Gibbs energy function of an alloy phase should be derived from Gibbs energy partition function constructed of alloy gene sequence and their Gibbs energy sequence. Second, the six rules for establishing alloy gene Gibbs energy partition function have been discovered, and it has been specially proved that the probabilities of structure units occupied at the Gibbs energy levels in the degeneracy factor for calculating configuration entropy should be degenerated as ones of component atoms occupied at the lattice points. Third, the main characteristics unexpected by today’s researchers are as follows. There exists a single-phase boundary curve without two-phase region coexisting by the ordered and disordered phases. The composition and temperature of the top point on the phase-boundary curve are far away from those of the critical point of the Au3Cu compound; At 0 K, the composition of the lowest point on the composition-dependent Gibbs energy curve is notably deviated from that of the Au3Cu compounds. The theoretical limit composition range of long range ordered Au3Cu-type alloys is determined by the first jumping order degree. 展开更多
关键词 Au3Cu compound Au3Cu-type sublattice system alloy gene Gibbs energy partition function equilibrium holographic network phase diagrams systematic metal materials science
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Performance analysis in 3G/ad hoc integrated network
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作者 李旭杰 沈连丰 《Journal of Southeast University(English Edition)》 EI CAS 2011年第3期233-238,共6页
An analytical approach to evaluate the performance of the 3G/ad hoc integrated network is presented. A channel model capturing both path loss and shadowing is applied to the analysis so as to characterize power fallof... An analytical approach to evaluate the performance of the 3G/ad hoc integrated network is presented. A channel model capturing both path loss and shadowing is applied to the analysis so as to characterize power falloff vs. distance. The 3G/ad hoc integrated network scenario model is introduced briefly. Based on this model, several performances of the 3G/ ad hoc integrated network in terms of outage probability, call dropping probability and new call blocking probability are evaluated. The corresponding performance formulae are deduced in accordance with the analytical models. Meanwhile, the formula of the 3G/ad hoc integrated network capacity is deduced on the basis of the formula of the outage probability. It is observed from extensive simulation and numerical analysis that the 3G/ad hoc integrated network remarkably outperforms the 3G network with regards to the network performance. This derived evaluation approach can be applied into planning and optimization of the 3G/ad hoc network. 展开更多
关键词 performance analysis 3G network ad hoc network integrated network
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基于FS-YOLOv3及多尺度特征融合的棉布瑕疵检测 被引量:10
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作者 刘露露 李波 +1 位作者 何征 姚为 《中南民族大学学报(自然科学版)》 CAS 北大核心 2021年第1期95-101,共7页
为解决传统棉布生产工艺中瑕疵检测成本高、精度低、速度慢等问题,提出一种FS-YOLOv3(Four Scales YOLOv3)网络来自动检测棉布瑕疵.该网络结合K-Means++聚类算法,以交并比为距离度量获取较好尺寸的锚框,提高检测速度.设计了4个不同尺度... 为解决传统棉布生产工艺中瑕疵检测成本高、精度低、速度慢等问题,提出一种FS-YOLOv3(Four Scales YOLOv3)网络来自动检测棉布瑕疵.该网络结合K-Means++聚类算法,以交并比为距离度量获取较好尺寸的锚框,提高检测速度.设计了4个不同尺度的卷积特征图与深度残差网络中相应尺度的特征图进行融合,有效地学习样本特征.将Softer NMS算法作为预测框过滤机制,使得高分类置信度的边框位置更为准确.实验结果表明:使用FS-YOLOv3网络能有效提高低对比度、小尺度目标的棉布瑕疵检测精度,整体性能优于传统的检测方法. 展开更多
关键词 fs-yolov3网络 瑕疵检测 多尺度特征融合 聚类 Softer NMS算法
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2020珠峰高程测量BDS-3数据质量分析 被引量:1
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作者 杨强 党亚民 +2 位作者 蒋光伟 马新莹 孙洋洋 《导航定位学报》 北大核心 2025年第2期20-27,共8页
2020年珠峰高程测量首次以国产北斗卫星导航系统(BDS)接收机为核心装备,获取了北斗三号全球卫星导航系统(BDS-3)高精度观测数据。为了确保成果的可靠性,利用天宝(Trimble)接收机对国产接收机BDS-3观测结果进行检核。针对珠峰地形环境限... 2020年珠峰高程测量首次以国产北斗卫星导航系统(BDS)接收机为核心装备,获取了北斗三号全球卫星导航系统(BDS-3)高精度观测数据。为了确保成果的可靠性,利用天宝(Trimble)接收机对国产接收机BDS-3观测结果进行检核。针对珠峰地形环境限制导致全球卫星导航系统(GNSS)观测网形不佳、峰顶GNSS观测时间短等难题,提出三级控制策略相结合的GNSS观测网数据处理方案,通过构建地区GNSS基准网、局部GNSS控制网和峰顶联测网,在极其有限的珠峰观测时段内最大化地优化提取高质量GNSS观测数据。为了验证BDS-3观测数据的精度,对比全球定位系统(GPS)和BDS-3数据解算结果,并检核GNSS数据处理与分析软件(GPAS)/加米特(GAMIT)2种软件的BDS解算结果,结果表明,BDS-3处理结果精度与GPS成果精度相当,高程方向精度均优于2 cm,坐标差异均优于1 cm,验证了本次珠峰测高BDS-3观测成果的精度和可靠性。 展开更多
关键词 珠穆朗玛峰 数据处理 全球卫星导航系统(GNSS)控制网 高程测量 北斗三号全球卫星导航系统(BDS-3) 质量评估
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Array Networks为3G清除安全障碍
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作者 鲁义轩 《通信世界》 2009年第20期I0019-I0019,共1页
刚刚上市的Array Networks在金融危机中将位于北京的Array Networks(北京)公司搬人了CBD核心区,做好了新一轮扩张的准备,同时该公司CEO赵耀对外宣布的新产品计划锁定了中国3G市场,可见,这家全球领先的SSLVPN以及负载均衡解决方案... 刚刚上市的Array Networks在金融危机中将位于北京的Array Networks(北京)公司搬人了CBD核心区,做好了新一轮扩张的准备,同时该公司CEO赵耀对外宣布的新产品计划锁定了中国3G市场,可见,这家全球领先的SSLVPN以及负载均衡解决方案提供商的3G准备已经完成。 展开更多
关键词 networkS 3G市场 安全 清除 金融危机 产品计划 CBD CEO
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丙烯酰胺基互穿网络的制备及对Fe^(3+)的吸附
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作者 薛丹 郭笑一 +1 位作者 张浩田 李善建 《工程塑料应用》 北大核心 2025年第1期15-22,共8页
以磺酸基甜菜碱为互穿物,以丙烯酰胺(AM)、N-乙烯基吡咯烷酮和苯乙烯为单体,过硫酸铵为引发剂,N,N′-亚甲基双丙烯酰胺为交联剂,通过两步聚合法制备AM基互穿网络。该网络可对Fe^(3+)形成高效且快速的吸附,25℃下用量为0.2 g/50 mL,吸附2... 以磺酸基甜菜碱为互穿物,以丙烯酰胺(AM)、N-乙烯基吡咯烷酮和苯乙烯为单体,过硫酸铵为引发剂,N,N′-亚甲基双丙烯酰胺为交联剂,通过两步聚合法制备AM基互穿网络。该网络可对Fe^(3+)形成高效且快速的吸附,25℃下用量为0.2 g/50 mL,吸附2.5 h后达到平衡,最大吸附量为1.90 mg/g,此时吸附率可达76%;在50000 mg/L的矿化度下,对Fe^(3+)的吸附量仍能达到1.76 mg/g,在实际应用中,Fe^(3+)去除率可达80%以上。Fe^(3+)与互穿网络中的氨基、羰基和磺酸基形成配位键,吸附后荧光强度明显减小,并以单分子层形式吸附,化学控制为主,符合Langmuir等温吸附模型和准二级动力学模型。 展开更多
关键词 丙烯酰胺 互穿网络 Fe^(3+) 静态吸附 耐盐性能
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Small but influential:the role of microRNAs on gene regulatory network and 3′UTR evolution 被引量:15
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作者 Rui Zhang Bing Su 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2009年第1期1-6,共6页
MicroRNAs (miRNAs) are endogenous -22 nucleotide noncoding RNAs that regulate the expression of complementary messenger RNAs (mRNAs). Thousands of miRNA genes have been found in diverse species, and many of them a... MicroRNAs (miRNAs) are endogenous -22 nucleotide noncoding RNAs that regulate the expression of complementary messenger RNAs (mRNAs). Thousands of miRNA genes have been found in diverse species, and many of them are highly conserved. With the miRNA roles identified in nearly all aspects of biological processes, evidence is mounting that miRNAs could represent a new layer of regulatory network, and their regulatory effect might be much more pervasive than previously suspected. Here we focus on the posttranscriptional level gene regulation of miRNAs in animals and review how the miRNAs act to sustain and shape up the expression profiles of specific cell types; how the miRNAs integrate into the existing gene regulatory networks; and how the miRNAs influence the evolution of 3'UTR of mammalian mRNAs. 展开更多
关键词 MIRNA gene expression regulatory network 3'UTR evolution
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Constructing two-scale network microstructure with nano-Ti5Si3 for superhigh creep resistance 被引量:21
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作者 Y.Jiao L.J.Huang +4 位作者 S.L.Wei H.X.Peng Q.An S.Jiang L.Geng 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2019年第8期1532-1542,共11页
The improvement of mechanical properties must be achieved by designing and constructing more suitable microstructure,such as hierarchical microstructure.In order to significantly enhance the creep resistance of titani... The improvement of mechanical properties must be achieved by designing and constructing more suitable microstructure,such as hierarchical microstructure.In order to significantly enhance the creep resistance of titanium matrix composites(TMCs),two-scale network microstructure was constructed including the first-scale network(<150μm)with micro-TiB whisker(TiBw)reinforcement and the second-scale network(<30μm)with nano-Ti5Si3 reinforcement by powder metallurgy and in-situ synthesis.The results showed that the creep rate of the composite was remarkably reduced by an order of magnitude compared with the Ti6Al4V alloy at 550℃,600℃,650℃ under the stresses between 100 MPa and 350 MPa.Moreover,the rupture time of the composite was increased by 20 times,compared with that of the Ti6Al4 Valloy at 550℃/300 MPa.The superior creep resistance could be attributed to the hierarchical microstructure.The micro-TiBw reinforcement in the first-scale network boundary contributed to creep resistance primarily by blocking grain boundary sliding,while the nano-Ti5Si3 particle in the second-scale network boundary mainly by hindering phase boundary sliding.In addition,the nano-Ti5Si3 particle was dissolved,and precipitated with smaller size than the primary Ti5Si3.This phenomenon was attributed to Si element diffusion under high temperature and external stress,which could further continuously enhance the creep resistance.Finally,the creep rate during steady-state stage was significantly decreased,which manifested superior creep resistance of the composite. 展开更多
关键词 Titanium matrix composite TWO-SCALE network MICROSTRUCTURE Nano-Ti5Si3 Creep Powder METALLURGY
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