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Intelligent Parameter Decision-Making and Multi-objective Prediction for Multi-layer and Multi-pass LDED Process
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作者 Li Yaguan Nie Zhenguo +2 位作者 Li Huilin Wang Tao Huang Qingxue 《稀有金属材料与工程》 北大核心 2026年第1期47-58,共12页
The key parameters that characterize the morphological quality of multi-layer and multi-pass metal laser deposited parts are the surface roughness and the error between the actual printing height and the theoretical m... The key parameters that characterize the morphological quality of multi-layer and multi-pass metal laser deposited parts are the surface roughness and the error between the actual printing height and the theoretical model height.The Taguchi method was employed to establish the correlations between process parameter combinations and multi-objective characterization of metal deposition morphology(height error and roughness).Results show that using the signal-to-noise ratio and grey relational analysis,the optimal parameter combination for multi-layer and multi-pass deposition is determined as follows:laser power of 800 W,powder feeding rate of 0.3 r/min,step distance of 1.6 mm,and scanning speed of 20 mm/s.Subsequently,a Genetic Bayesian-back propagation(GB-BP)network is constructed to predict multi-objective responses.Compared with the traditional back propagation network,the GB-back propagation network improves the prediction accuracy of height error and surface roughness by 43.14%and 71.43%,respectively.This network can accurately predict the multi-objective characterization of morphological quality of multi-layer and multi-pass metal deposited parts. 展开更多
关键词 multi-layer and multi-pass laser cladding Taguchi method grey relational analysis GB-BP network
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No egg or nestling-retrieval behavior in a cavity-nesting cuckoo host
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作者 Chenyang Zhao Jinggang Zhang +4 位作者 Peter Santema Zixuan Lin Jianqiang Li Wenhong Deng Bart Kempenaers 《Avian Research》 2026年第1期102-107,共6页
The arms race between avian brood parasites and their hosts provides a classic model for studying coevolution.In one of the most widespread obligate brood parasites,the Common Cuckoo(Cuculus canorus),chicks typically ... The arms race between avian brood parasites and their hosts provides a classic model for studying coevolution.In one of the most widespread obligate brood parasites,the Common Cuckoo(Cuculus canorus),chicks typically evict all host progeny(eggs and nestlings)from the nest cup,resulting in complete reproductive failure for the host.Host parents of Common Cuckoos could thus potentially benefit from retrieving evicted eggs and nestlings into the nest cup.However,whether hosts of the Common Cuckoo exhibit such retrieval behavior has been scarcely studied.In this study,we experimentally investigated the occurrence of retrieval in a nestbox-breeding population of Daurian Redstarts(Phoenicurus auroreus),a common cavity-nesting host of the Common Cuckoo.To test the redstarts'response to an egg or a nestling outside the nest cup,we experimentally placed either a conspecific egg,a model cuckoo egg,or a redstart nestling near the rim of the nest cup.We found that redstarts never showed retrieval behavior of either eggs or nestlings.All hosts ignored the experimental nestling and conspecific egg,but most ejected the model cuckoo egg from the nestbox.Our results suggest that selection for retrieval behavior in this cavity-nesting host may be weak or even negative.We discuss several ecological and evolutionary factors that may explain the absence of retrieval in this system. 展开更多
关键词 Brood parasitism Daurian Redstart Egg rejection Egg retrieval Nestling retrieval
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Hybrid Bayesian-Machine Learning Framework for Multi-Profile Atmospheric Retrieval from Hyperspectral Infrared Observations
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作者 Senyi KONG Lei BI +2 位作者 Wei HAN Ruoying YIN Honglei ZHANG 《Advances in Atmospheric Sciences》 2026年第2期373-389,共17页
Accurate retrieval of atmospheric vertical profiles is critical for improving weather prediction and climate monitoring.However,the complexity of atmospheric processes in cloudy regions poses challenges compared to th... Accurate retrieval of atmospheric vertical profiles is critical for improving weather prediction and climate monitoring.However,the complexity of atmospheric processes in cloudy regions poses challenges compared to those of clear sky scenarios.This study presents a novel framework that integrates Bayesian optimization and machine learning approaches to retrieve atmospheric vertical profiles—including temperature,humidity,ozone concentration,cloud fraction,ice water content(IWC),and liquid water content(LWC)—from hyperspectral infrared observations.Specifically,a Bayesian method was used to refine ERA5 reanalysis data by minimizing brightness temperature(BT)discrepancies against FY-4B Geostationary Interferometric Infrared Sounder(GIIRS)observations,generating a high-quality profile database(~2.8 million profiles)across diverse weather systems.The optimized profiles improve radiative consistency,reducing BT biases from>40 K to<10 K in cloudy regions.To further overcome the limitations of the Bayesian method,we developed a Transformer-Resnet hybrid model(TERNet),which achieved superior performance with RMSE values of 1.61 K(temperature),5.77%(humidity),and 2.25×10^(–6)/6.09×10^(–6)kg kg^(–1)(IWC/LWC)across the entire vertical levels in all-sky conditions.The TERNet outperforms both ERA5 in cloud parameter retrieval and the GIIRS L2 product in thermodynamic profiling.Independent verification with radiosonde and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations(CALIPSO)datasets confirms the framework's reliability across various meteorological regimes.This work demonstrates the capability of combining physics-informed Bayesian methods with data-driven machine learning to fully exploit hyperspectral IR data. 展开更多
关键词 BAYESIAN machine learning retrieval GIIRS atmospheric profile
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Modeling and Vulnerability Analysis of Multi-layer Urban Electric-transportation Interdependent Networks Under Extreme Events
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作者 Gengming Liu Wenxia Liu Qingxin Shi 《CSEE Journal of Power and Energy Systems》 2026年第1期466-480,共15页
The increasing electrification of urban transportation,i.e.,subways and electric vehicles(EV),brings more interactions between the power system and transportation system and further results in fault propagation across... The increasing electrification of urban transportation,i.e.,subways and electric vehicles(EV),brings more interactions between the power system and transportation system and further results in fault propagation across them.To analyze vulnerability of the coupling system under extreme events,this paper establishes a multi-layer urban electric-transportation interdependent network(ETIN)model.First,a weighted coupled metro-road traffic network(CTN)model and network path planning approach are proposed.A prospect theory-based failure load redistribution(FLR)method is further established to account for uncertainty of TN link capacity affected by power supply.Second,topology and emergency control strategy of power network(PN)are modeled,followed by formulation of multi-layer ETIN model.In particular,the inter-layer fault propagation from PN to TN is modeled based on power supply correlation strength,while from TN to PN is modeled based on traffic flow.A few indexes are then defined to quantify vulnerability of ETIN under deliberate attack.Finally,the proposed method is verified on an electric-transportation system to show influence of fault propagations within ETIN on its vulnerability under extreme events. 展开更多
关键词 Electric-traffic interdependent system metro-road traffic coupled network multi-layer interdependent network vulnerability analysis
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Endocrine stimulation in men with non-obstructive azoospermia and low serum testosterone prior to micro-TESE:hormonal response as a predictor of sperm retrieval
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作者 Shlomi Barak NetanelWaldenberg +3 位作者 Aharon Peretz Reut Bartoov Guy Bar Snir Dekalo 《The Canadian Journal of Urology》 2026年第1期135-142,共8页
Background:Hormonal treatment and response as a predictor of sperm retrieval prior to microdissection testicular sperm extraction(micro-TESE)are not well established in the current literature.This study aimed to inves... Background:Hormonal treatment and response as a predictor of sperm retrieval prior to microdissection testicular sperm extraction(micro-TESE)are not well established in the current literature.This study aimed to investigate the hormonal response as a predictor of sperm retrieval among men with nonobstructive azoospermia(NOA).Methods:Seventy-seven consecutive patients who had testosterone levels≤14 nmol/L were treated medically with an aromatase inhibitor or recombinant human chorionic gonadotropin(rec-hCG)prior to micro-TESE and were included.Thirty-four(44.2%)had unexplained NOA(UNEX),25(32.5%)had Klinefelter syndrome(KS),8(10.4%)had a history of cryptorchidism(UDT),4(5.2%)had microdeletion of the Azoospermia factor C(AZFc),and 6(7.8%)were treated previously with chemotherapy.Baseline and post-treatment serum hormonal levels were documented.Pre-op testosterone levels were entered into binary logistic regressions with age,Follicle-stimulating hormone(FSH),and Luteinizing hormone(LH)levels to test for significance with sperm retrieval.We then built logistic regression models to identify predictors of successful surgical sperm retrieval(SSR).Results:Forty-five patients(58%)had successful retrieval.In 32 patients(42%),no sperm was retrieved.Both the mean pre-op testosterone and the mean testosterone change between the two groups were significant(p=0.02 and p=0.011,respectively).Receiver operating characteristic(ROC)analysis demonstrated an area under the curve(AUC)of 0.785(95%CI=0.685-0.886,p<0.001).The Youden index coefficient was calculated for KS and UNEX.The cut-off point for KS was established at 0.764(sensitivity=0.875,false positive rate[FPR]=0.111),and 0.215 for UNEX(sensitivity=0.438,FPR=0.222).We also observed a correlation between age and SSR(p=0.05).In KS patients,SSR was determined by pre-op testosterone levels irrespective of age.Conclusion:Pre-operative hormonal response is a predictor for SSR in NOA patients who were treated medically.This data may help during pre-operative counselling. 展开更多
关键词 non-obstructive azoospermia(NOA) microdissection testicular sperm extraction(micro-TESE) endocrine stimulation male infertility sperm retrieval
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Medical Image Retrieval Based on Multi-Layer Resampling Template
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作者 WANG Xin-rui YANG Yun-feng 《Computer Aided Drafting,Design and Manufacturing》 2014年第4期69-73,共5页
Medical image application in clinical diagnosis and treatment is becoming more and more widely, How to use a large number of images in the image management system and it is a very important issue how to assist doctors... Medical image application in clinical diagnosis and treatment is becoming more and more widely, How to use a large number of images in the image management system and it is a very important issue how to assist doctors to analyze and diagnose. This paper studies the medical image retrieval based on multi-layer resampling template under the thought of the wavelet decomposition, the image retrieval method consists of two retrieval process which is coarse and fine retrieval. Coarse retrieval process is the medical image retrieval process based on the image contour features. Fine retrieval process is the medical image retrieval process based on multi-layer resampling template, a multi-layer sampling operator is employed to extract image resampling images each layer, then these resampling images are retrieved step by step to finish the process from coarse to fine retrieval. 展开更多
关键词 medical image retrieval RESAMPLING mutual information
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Multi-layer multi-pass friction rolling additive manufacturing of Al alloy:Toward complex large-scale high-performance components 被引量:2
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作者 Haibin Liu Run Hou +2 位作者 Chenghao Wu Ruishan Xie Shujun Chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期425-438,共14页
At present,the emerging solid-phase friction-based additive manufacturing technology,including friction rolling additive man-ufacturing(FRAM),can only manufacture simple single-pass components.In this study,multi-laye... At present,the emerging solid-phase friction-based additive manufacturing technology,including friction rolling additive man-ufacturing(FRAM),can only manufacture simple single-pass components.In this study,multi-layer multi-pass FRAM-deposited alumin-um alloy samples were successfully prepared using a non-shoulder tool head.The material flow behavior and microstructure of the over-lapped zone between adjacent layers and passes during multi-layer multi-pass FRAM deposition were studied using the hybrid 6061 and 5052 aluminum alloys.The results showed that a mechanical interlocking structure was formed between the adjacent layers and the adja-cent passes in the overlapped center area.Repeated friction and rolling of the tool head led to different degrees of lateral flow and plastic deformation of the materials in the overlapped zone,which made the recrystallization degree in the left and right edge zones of the over-lapped zone the highest,followed by the overlapped center zone and the non-overlapped zone.The tensile strength of the overlapped zone exceeded 90%of that of the single-pass deposition sample.It is proved that although there are uneven grooves on the surface of the over-lapping area during multi-layer and multi-pass deposition,they can be filled by the flow of materials during the deposition of the next lay-er,thus ensuring the dense microstructure and excellent mechanical properties of the overlapping area.The multi-layer multi-pass FRAM deposition overcomes the limitation of deposition width and lays the foundation for the future deposition of large-scale high-performance components. 展开更多
关键词 aluminum alloy additive manufacturing SOLID-STATE friction stir welding multi-layer multi-pass
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Efficient Method for Trademark Image Retrieval: Leveraging Siamese and Triplet Networks with Examination-Informed Loss Adjustment
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作者 Thanh Bui-Minh Nguyen Long Giang Luan Thanh Le 《Computers, Materials & Continua》 2025年第7期1203-1226,共24页
Image-based similar trademark retrieval is a time-consuming and labor-intensive task in the trademark examination process.This paper aims to support trademark examiners by training Deep Convolutional Neural Network(DC... Image-based similar trademark retrieval is a time-consuming and labor-intensive task in the trademark examination process.This paper aims to support trademark examiners by training Deep Convolutional Neural Network(DCNN)models for effective Trademark Image Retrieval(TIR).To achieve this goal,we first develop a novel labeling method that automatically generates hundreds of thousands of labeled similar and dissimilar trademark image pairs using accompanying data fields such as citation lists,Vienna classification(VC)codes,and trademark ownership information.This approach eliminates the need for manual labeling and provides a large-scale dataset suitable for training deep learning models.We then train DCNN models based on Siamese and Triplet architectures,evaluating various feature extractors to determine the most effective configuration.Furthermore,we present an Adapted Contrastive Loss Function(ACLF)for the trademark retrieval task,specifically engineered to mitigate the influence of noisy labels found in automatically created datasets.Experimental results indicate that our proposed model(Efficient-Net_v21_Siamese)performs best at both True Negative Rate(TNR)threshold levels,TNR 0.9 and TNR 0.95,with==respective True Positive Rates(TPRs)of 77.7%and 70.8%and accuracies of 83.9%and 80.4%.Additionally,when testing on the public trademark dataset METU_v2,our model achieves a normalized average rank(NAR)of 0.0169,outperforming the current state-of-the-art(SOTA)model.Based on these findings,we estimate that considering only approximately 10%of the returned trademarks would be sufficient,significantly reducing the review time.Therefore,the paper highlights the potential of utilizing national trademark data to enhance the accuracy and efficiency of trademark retrieval systems,ultimately supporting trademark examiners in their evaluation tasks. 展开更多
关键词 TRADEMARK image retrieval similar search similar retrieval content-based image retrieval similar ranking contrastive learning Siamese TRIPLET citation list
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Retrieval of Ozone Profiles Using a Weighted Multiplicative Algebraic Reconstruction Technique from SCIAMACHY Limb Scattering Observations
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作者 Fang Zhu Fuqi Si +3 位作者 Ke Dou Kai Zhan Haijin Zhou Yuhan Luo 《Journal of Earth Science》 2025年第1期314-326,共13页
This study describes the use of the weighted multiplicative algebraic reconstruction technique(WMART)to obtain vertical ozone profiles from limb observations performed by the scanning imaging absorption spectrometer f... This study describes the use of the weighted multiplicative algebraic reconstruction technique(WMART)to obtain vertical ozone profiles from limb observations performed by the scanning imaging absorption spectrometer for atmospheric chartography(SCIAMACHY).This technique is based on SaskMART(the combination of the multiplicative algebraic reconstruction technique and SaskTRAN radiative transfer model),which was originally developed for optical spectrometer and infrared imaging system(OSIRIS)data.One of the objectives of this study was to obtain consistent ozone profiles from the two satellites.In this study,the WMART algorithm is combined with a radiative transfer model(SCIATRAN),as well as a set of measurement vectors comprising five Hartley pairing vectors(HPVs)and one Chappuis triplet vector(CTV),to retrieve ozone profiles in the altitude range of 10–69 km.Considering that the weighting factors in WMART have a significant effect on the retrievals,we propose a novel approach to calculate the pair/triplet weighting factors using wavelength weighting functions.The results of the application of the proposed ozone retrieval scheme are compared with the SCIAMACHY v3.5 ozone product by University of Bremen and validated against profiles derived from other passive satellite observations or measured by ozonesondes.Between 18 and 55 km,the retrieved ozone profiles typically agree with data from the SCIAMACHY ozone product within 5%for tropics and middle latitudes,whereas a negative deviation exists between 35 and 50 km for northern high latitudes,with a deviation of less than 10%above 50 km.Comparison of the retrieved profiles with microwave limb sounder(MLS)v5.0 indicates that the difference is within±5%between 18 and 55 km,and an agreement within 10%is achieved in other altitudes for tropics and middle latitudes.Comparison of the retrieved profiles with OSIRIS v7.1 indicates that the average deviation is within±5%between 20 and 59 km,and difference of approximately 10%is achieved below 20 km.Compared with ozonesondes data,a general validity of the retrievals is no more than 5%between 15 and 30 km. 展开更多
关键词 retrievalS OZONE profiles WMART SCIAMACHY LIMB
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Dynamic Routing of Theta-Frequency Synchrony in the Amygdalo-Hippocampal-Entorhinal Circuit Coordinates Retrieval of Competing Memories
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作者 Jiahua Zheng Yiqi Sun +4 位作者 Fuhai Wang Zhongyu Xie Qianyun Wang Jian-Ya Peng Jianguang Ni 《Neuroscience Bulletin》 2025年第4期713-718,共6页
DDeeaarr EEddiittoorr,,The encoding and retrieval of emotional memories demands intricate interplay within the limbic network,where the network state is subject to significant reconfiguration by learning-induced plast... DDeeaarr EEddiittoorr,,The encoding and retrieval of emotional memories demands intricate interplay within the limbic network,where the network state is subject to significant reconfiguration by learning-induced plasticity,behavioral state,and contextual information[1]. 展开更多
关键词 competing memories limbic networkwhere emotional memories theta frequency synchrony encoding retrieval emotional memories dynamic routing amygdalo hippocampal entorhinal circuit memory retrieval
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EffNet-CNN:A Semantic Model for Image Mining&Content-Based Image Retrieval
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作者 Rajendran Thanikachalam Anandhavalli Muniasamy +1 位作者 Ashwag Alasmari Rajendran Thavasimuthu 《Computer Modeling in Engineering & Sciences》 2025年第5期1971-2000,共30页
Content-Based Image Retrieval(CBIR)and image mining are becoming more important study fields in computer vision due to their wide range of applications in healthcare,security,and various domains.The image retrieval sy... Content-Based Image Retrieval(CBIR)and image mining are becoming more important study fields in computer vision due to their wide range of applications in healthcare,security,and various domains.The image retrieval system mainly relies on the efficiency and accuracy of the classification models.This research addresses the challenge of enhancing the image retrieval system by developing a novel approach,EfficientNet-Convolutional Neural Network(EffNet-CNN).The key objective of this research is to evaluate the proposed EffNet-CNN model’s performance in image classification,image mining,and CBIR.The novelty of the proposed EffNet-CNN model includes the integration of different techniques and modifications.The model includes the Mahalanobis distance metric for feature matching,which enhances the similarity measurements.The model extends EfficientNet architecture by incorporating additional convolutional layers,batch normalization,dropout,and pooling layers for improved hierarchical feature extraction.A systematic hyperparameter optimization using SGD,performance evaluation with three datasets,and data normalization for improving feature representations.The EffNet-CNN is assessed utilizing precision,accuracy,F-measure,and recall metrics across MS-COCO,CIFAR-10 and 100 datasets.The model achieved accuracy values ranging from 90.60%to 95.90%for the MS-COCO dataset,96.8%to 98.3%for the CIFAR-10 dataset and 92.9%to 98.6%for the CIFAR-100 dataset.A validation of the EffNet-CNN model’s results with other models reveals the proposed model’s superior performance.The results highlight the potential of the EffNet-CNN model proposed for image classification and its usefulness in image mining and CBIR. 展开更多
关键词 Image mining CBIR semantic features EffNet-CNN image retrieval
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A Multi-Layer Progressive Analysis Method for Collision Energy Flow in Rail Trains
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作者 Jingke Zhang Tao Zhu +4 位作者 Xiaorui Wang Bing Yang Shoune Xiao Guangwu Yang Yuru Li 《Chinese Journal of Mechanical Engineering》 2025年第5期425-439,共15页
The huge impact kinetic energy cannot be quickly dissipated by the energy-absorbing structure and transferred to the other vehicle through the car body structure,which will cause structural damage and threaten the liv... The huge impact kinetic energy cannot be quickly dissipated by the energy-absorbing structure and transferred to the other vehicle through the car body structure,which will cause structural damage and threaten the lives of the occupants.Therefore,it is necessary to understand the laws of energy conversion,dissipation and transfer during train collisions.This study proposes a multi-layer progressive analysis method of energy flow during train collisions,considering the characteristics of the train.In this method,the train collision system is divided into conversion,dissipation,and transfer layers from the perspective of the train,collision interface,and car body structure to analyze the energy conversion,dissipation and transfer characteristics.Taking the collision process of a rail train as an example,a train collision energy transfer path analysis model was established based on power flow theory.The results show that when the maximum mean acceleration of the vehicle meets the standard requirements,the jerk may exceed the allowable limit of the human body,and there is a risk of injury to the occupants of a secondary collision.The decay rate of the collision energy along the direction of train operation reaches 79%.As the collision progresses,the collision energy gradually converges in the structure with holes,and the structure deforms when the gathered energy is greater than the maximum energy the structure can withstand.The proposed method helps to understand the train collision energy flow law and provides theoretical support for the train crashworthiness design in the future. 展开更多
关键词 Train Cllision multi-layer Progression Energy Flow Energy Conversion Energy Dissipation Energy Transfer
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Retrieval analysis in total knee arthroplasty
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作者 Emerito Carlos Rodriguez-Merchan William J Ribbans 《World Journal of Orthopedics》 2025年第3期28-34,共7页
Retrieval analysis in total knee arthroplasty(TKA)has been little studied in the literature.A narrative review of the literature to understand the current importance of retrieval analysis in TKA has been conducted.On ... Retrieval analysis in total knee arthroplasty(TKA)has been little studied in the literature.A narrative review of the literature to understand the current importance of retrieval analysis in TKA has been conducted.On August 27,2024,a literature search was performed in PubMed using“TKA retrieval analysis”as keywords.A total of 160 articles were found,of which only 19 were analyzed because they were directly related to the subject of this article.Rotating-platform(mobile-bearing)TKA has no surface damage advantage over fixed-bearing TKA.TKAs with central locking mechanisms are more prone to debond from the cement mantle.No major wear of the polyethylene(PE)component in TKA using oxidized zirconium components occurs.Femoral components of cobalt-chromium roughen more than oxidized zirconium femoral components.The use of a polished tibial tray over an unpolished design is advised.At short-run assessment(15 months on average),antioxidant-stabilized highly crosslinked PE components are not clinically different in surface damage,density of crosslinking,or oxidation compared to standard remelted highly crosslinked PE components.A correlation between implant position and PE component surface damage has been reported.It shows the importance of optimizing component position to reduce PE component damage.Contemporary knee tumor megaendoprostheses show notable volumetric metal wear originated at the rotating hinge.Retrieval analysis in TKA renders relevant data on how different prosthetic designs described in the literature perform.Such information can help to improve future prosthetic designs to increase prosthetic survival. 展开更多
关键词 Total knee arthroplasty retrieval analysis RESULTS KNEE ORTHOPEDICS
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Intrusion Detection Model on Network Data with Deep Adaptive Multi-Layer Attention Network(DAMLAN)
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作者 Fatma S.Alrayes Syed Umar Amin +2 位作者 Nada Ali Hakami Mohammed K.Alzaylaee Tariq Kashmeery 《Computer Modeling in Engineering & Sciences》 2025年第7期581-614,共34页
The growing incidence of cyberattacks necessitates a robust and effective Intrusion Detection Systems(IDS)for enhanced network security.While conventional IDSs can be unsuitable for detecting different and emerging at... The growing incidence of cyberattacks necessitates a robust and effective Intrusion Detection Systems(IDS)for enhanced network security.While conventional IDSs can be unsuitable for detecting different and emerging attacks,there is a demand for better techniques to improve detection reliability.This study introduces a new method,the Deep Adaptive Multi-Layer Attention Network(DAMLAN),to boost the result of intrusion detection on network data.Due to its multi-scale attention mechanisms and graph features,DAMLAN aims to address both known and unknown intrusions.The real-world NSL-KDD dataset,a popular choice among IDS researchers,is used to assess the proposed model.There are 67,343 normal samples and 58,630 intrusion attacks in the training set,12,833 normal samples,and 9711 intrusion attacks in the test set.Thus,the proposed DAMLAN method is more effective than the standard models due to the consideration of patterns by the attention layers.The experimental performance of the proposed model demonstrates that it achieves 99.26%training accuracy and 90.68%testing accuracy,with precision reaching 98.54%on the training set and 96.64%on the testing set.The recall and F1 scores again support the model with training set values of 99.90%and 99.21%and testing set values of 86.65%and 91.37%.These results provide a strong basis for the claims made regarding the model’s potential to identify intrusion attacks and affirm its relatively strong overall performance,irrespective of type.Future work would employ more attempts to extend the scalability and applicability of DAMLAN for real-time use in intrusion detection systems. 展开更多
关键词 Intrusion detection deep adaptive networks multi-layer attention DAMLAN network security anomaly detection
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A Fully Homomorphic Encryption Scheme Suitable for Ciphertext Retrieval
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作者 Ronglei Hu ChuceHe +3 位作者 Sihui Liu Dong Yao Xiuying Li Xiaoyi Duan 《Computers, Materials & Continua》 2025年第7期937-956,共20页
Ciphertext data retrieval in cloud databases suffers from some critical limitations,such as inadequate security measures,disorganized key management practices,and insufficient retrieval access control capabilities.To ... Ciphertext data retrieval in cloud databases suffers from some critical limitations,such as inadequate security measures,disorganized key management practices,and insufficient retrieval access control capabilities.To address these problems,this paper proposes an enhanced Fully Homomorphic Encryption(FHE)algorithm based on an improved DGHV algorithm,coupled with an optimized ciphertext retrieval scheme.Our specific contributions are outlined as follows:First,we employ an authorization code to verify the user’s retrieval authority and perform hierarchical access control on cloud storage data.Second,a triple-key encryption mechanism,which separates the data encryption key,retrieval authorization key,and retrieval key,is designed.Different keys are provided to different entities to run corresponding system functions.The key separation architecture proves particularly advantageous in multi-verifier coexistence scenarios,environments involving untrusted third-party retrieval services.Finally,the enhanced DGHV-based retrieval mechanism extends conventional functionality by enabling multi-keyword queries with similarity-ranked results,thereby significantly improving both the functionality and usability of the FHE system. 展开更多
关键词 Cloud storage homomorphic encryption ciphertext retrieval identity authentication
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Event-Driven Attention Network:A Cross-Modal Framework for Efficient Image-Text Retrieval in Mass Gathering Events
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作者 Kamil Yasen Heyan Jin +4 位作者 Sijie Yang Li Zhan Xuyang Zhang Ke Qin Ye Li 《Computers, Materials & Continua》 2025年第5期3277-3301,共25页
Research on mass gathering events is critical for ensuring public security and maintaining social order.However,most of the existing works focus on crowd behavior analysis areas such as anomaly detection and crowd cou... Research on mass gathering events is critical for ensuring public security and maintaining social order.However,most of the existing works focus on crowd behavior analysis areas such as anomaly detection and crowd counting,and there is a relative lack of research on mass gathering behaviors.We believe real-time detection and monitoring of mass gathering behaviors are essential formigrating potential security risks and emergencies.Therefore,it is imperative to develop a method capable of accurately identifying and localizing mass gatherings before disasters occur,enabling prompt and effective responses.To address this problem,we propose an innovative Event-Driven Attention Network(EDAN),which achieves image-text matching in the scenario of mass gathering events with good results for the first time.Traditional image-text retrieval methods based on global alignment are difficult to capture the local details within complex scenes,limiting retrieval accuracy.While local alignment-based methods aremore effective at extracting detailed features,they frequently process raw textual features directly,which often contain ambiguities and redundant information that can diminish retrieval efficiency and degrade model performance.To overcome these challenges,EDAN introduces an Event-Driven AttentionModule that adaptively focuses attention on image regions or textual words relevant to the event type.By calculating the semantic distance between event labels and textual content,this module effectively significantly reduces computational complexity and enhances retrieval efficiency.To validate the effectiveness of EDAN,we construct a dedicated multimodal dataset tailored for the analysis of mass gathering events,providing a reliable foundation for subsequent studies.We conduct comparative experiments with other methods on our dataset,the experimental results demonstrate the effectiveness of EDAN.In the image-to-text retrieval task,EDAN achieved the best performance on the R@5 metric,while in the text-to-image retrieval task,it showed superior results on both R@10 and R@5 metrics.Additionally,EDAN excelled in the overall Rsummetric,achieving the best performance.Finally,ablation studies further verified the effectiveness of event-driven attention module. 展开更多
关键词 Mass gathering events image-text retrieval attention mechanism
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General analytical solutions for one-dimensional diffusion of degradable organic contaminant in the multi-layered media containing geomembranes
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作者 JIANG Wen-hao GE Shang-qi LI Jiang-shan 《Journal of Central South University》 2025年第10期3895-3910,共16页
In practical engineering construction,multi-layered barriers containing geomembranes are extensively applied to retard the migration of pollutants.However,the associated analytical theory on pollutants diffusion still... In practical engineering construction,multi-layered barriers containing geomembranes are extensively applied to retard the migration of pollutants.However,the associated analytical theory on pollutants diffusion still needs to be further improved.In this work,general analytical solutions are derived for one-dimensional diffusion of degradable organic contaminant(DOC)in the multi-layered media containing geomembranes under a time-varying concentration boundary condition,where the variable substitution and separated variable approaches are employed.These analytical solutions with clear expressions can be used not only to study the diffusion behaviors of DOC in bottom and vertical composite barrier systems,but also to verify other complex numerical models.The proposed general analytical solutions are then fully validated via three comparative analyses,including comparisons with the experimental measurements,an existing analytical solution,and a finite-difference solution.Ultimately,the influences of different factors on the composite cutoff wall’s(CCW,which consists of two soil-bentonite layers and a geomembrane)service performance are investigated through a composite vertical barrier system as the application example.The findings obtained from this investigation can provide scientific guidance for the barrier performance evaluation and the engineering design of CCWs.This application example also exhibits the necessity and effectiveness of the developed analytical solutions. 展开更多
关键词 general analytical solutions degradable organic contaminant diffusion behavior multi-layered media containing geomembranes composite barrier system
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Deep learning retrieval of 3D casting models combined with professional knowledge for process reuse
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作者 Xiao-long Pei Hua Hou +2 位作者 Li-wen Chen Zhi-qiang Duan Yu-hong Zhao 《China Foundry》 2025年第6期710-722,共13页
Accurate retrieval of casting 3D models is crucial for process reuse.Current methods primarily focus on shape similarity,neglecting process design features,which compromises reusability.In this study,a novel deep lear... Accurate retrieval of casting 3D models is crucial for process reuse.Current methods primarily focus on shape similarity,neglecting process design features,which compromises reusability.In this study,a novel deep learning retrieval method for process reuse was proposed,which integrates process design features into the retrieval of casting 3D models.This method leverages the comparative language-image pretraining(CLIP)model to extract shape features from the three views and sectional views of the casting model and combines them with process design features such as modulus,main wall thickness,symmetry,and length-to-height ratio to enhance process reusability.A database of 230 production casting models was established for model validation.Results indicate that incorporating process design features improves model accuracy by 6.09%,reaching 97.82%,and increases process similarity by 30.25%.The reusability of the process was further verified using the casting simulation software EasyCast.The results show that the process retrieved after integrating process design features produces the least shrinkage in the target model,demonstrating this method’s superior ability for process reuse.This approach does not require a large dataset for training and optimization,making it highly applicable to casting process design and related manufacturing processes. 展开更多
关键词 CASTING 3D model retrieval process reuse deep learning
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Toward a Large Language Model-Driven Medical Knowledge Retrieval and QA System:Framework Design and Evaluation
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作者 Yuyang Liu Xiaoying Li +6 位作者 Yan Luo Jinhua Du Ying Zhang Tingyu Lv Hao Yin Xiaoli Tang Hui Liu 《Engineering》 2025年第7期270-282,共13页
Recent advancements in large language models(LLMs)have driven remarkable progress in text process-ing,opening new avenues for medical knowledge discovery.In this study,we present ERQA,a mEdical knowledge Retrieval and... Recent advancements in large language models(LLMs)have driven remarkable progress in text process-ing,opening new avenues for medical knowledge discovery.In this study,we present ERQA,a mEdical knowledge Retrieval and Question-Answering framework powered by an enhanced LLM that integrates a semantic vector database and a curated literature repository.The ERQA framework leverages domain-specific incremental pretraining and conducts supervised fine-tuning on medical literature,enabling retrieval and question-answering(QA)tasks to be completed with high precision.Performance evaluations implemented on the coronavirus disease 2019(COVID-19)and TripClick data-sets demonstrate the robust capabilities of ERQA across multiple tasks.On the COVID-19 dataset,ERQA-13B achieves state-of-the-art retrieval metrics,with normalized discounted cumulative gain at top 10(NDCG@10)0.297,recall values at top 10(Recall@10)0.347,and mean reciprocal rank(MRR)=0.370;it also attains strong abstract summarization performance,with a recall-oriented understudy for gisting evaluation(ROUGE)-1 score of 0.434,and QA performance,with a bilingual evaluation understudy(BLEU)-1 score of 7.851.The comparable performance achieved on the TripClick dataset further under-scores the adaptability of ERQA across diverse medical topics.These findings suggest that ERQA repre-sents a significant step toward efficient biomedical knowledge retrieval and QA. 展开更多
关键词 Large language models Medical knowledge Information retrieval Vector database
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An Intelligent Visibility Retrieval Framework Combining Meteorological Factors and Image Features
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作者 MU Xi-yu ZHOU Yu-feng +7 位作者 XU Qi FENG Yi-fei LIU Ze-zhong CHENG Xiao-gang YAN Shu-qi YU Kun WU Hao YANG Hua-dong 《Journal of Tropical Meteorology》 2025年第5期545-555,共11页
Video imagery enables both qualitative characterization and quantitative retrieval of low-visibility conditions.These phenomena exhibit complex nonlinear dependencies on atmospheric processes,particularly during moist... Video imagery enables both qualitative characterization and quantitative retrieval of low-visibility conditions.These phenomena exhibit complex nonlinear dependencies on atmospheric processes,particularly during moisture-driven weather events such as fog,rain,and snow.To address this challenge,we propose a dual-branch neural architecture that synergistically processes optical imagery and multi-source meteorological data(temperature,humidity,and wind speed).The framework employs a convolutional neural network(CNN)branch to extract visibility-related visual features from video imagery sequences,while a parallel artificial neural network(ANN)branch decodes nonlinear relationships among the meteorological factors.Cross-modal feature fusion is achieved through an adaptive weighting layer.To validate the framework,multimodal Backpropagation-VGG(BP-VGG)and Backpropagation-ResNet(BP-ResNet)models are developed and trained/tested using historical imagery and meteorological observations from Nanjing Lukou International Airport.The results demonstrate that the multimodal networks reduce retrieval errors by approximately 8%–10%compared to unimodal networks relying solely on imagery.Among the multimodal models,BP-ResNet exhibits the best performance with a mean absolute percentage error(MAPE)of 8.5%.Analysis of typical case studies reveals that visibility fluctuates rapidly while meteorological factors change gradually,highlighting the crucial role of high-frequency imaging data in intelligent visibility retrieval models.The superior performance of BP-ResNet over BP-VGG is attributed to its use of residual blocks,which enables BP-ResNet to excel in multimodal processing by effectively leveraging data complementarity for synergistic improvements.This study presents an end-to-end intelligent visibility inversion framework that directly retrieves visibility values,enhancing its applicability across industries.However,while this approach boosts accuracy and applicability,its performance in critical low-visibility scenarios remains suboptimal,necessitating further research into more advanced retrieval techniques—particularly under extreme visibility conditions. 展开更多
关键词 multimodal neural network multisource factors intelligent visibility retrieval
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