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A Synthetic Speech Detection Model Combining Local-Global Dependency
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作者 Jiahui Song Yuepeng Zhang Wenhao Yuan 《Computers, Materials & Continua》 2026年第1期1312-1326,共15页
Synthetic speech detection is an essential task in the field of voice security,aimed at identifying deceptive voice attacks generated by text-to-speech(TTS)systems or voice conversion(VC)systems.In this paper,we propo... Synthetic speech detection is an essential task in the field of voice security,aimed at identifying deceptive voice attacks generated by text-to-speech(TTS)systems or voice conversion(VC)systems.In this paper,we propose a synthetic speech detection model called TFTransformer,which integrates both local and global features to enhance detection capabilities by effectively modeling local and global dependencies.Structurally,the model is divided into two main components:a front-end and a back-end.The front-end of the model uses a combination of SincLayer and two-dimensional(2D)convolution to extract high-level feature maps(HFM)containing local dependency of the input speech signals.The back-end uses time-frequency Transformer module to process these feature maps and further capture global dependency.Furthermore,we propose TFTransformer-SE,which incorporates a channel attention mechanism within the 2D convolutional blocks.This enhancement aims to more effectively capture local dependencies,thereby improving the model’s performance.The experiments were conducted on the ASVspoof 2021 LA dataset,and the results showed that the model achieved an equal error rate(EER)of 3.37%without data augmentation.Additionally,we evaluated the model using the ASVspoof 2019 LA dataset,achieving an EER of 0.84%,also without data augmentation.This demonstrates that combining local and global dependencies in the time-frequency domain can significantly improve detection accuracy. 展开更多
关键词 synthetic speech detection transformer local-global time-frequency domain
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Effect of measurement reduction on synthetic aperture x-ray ghost imaging
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作者 Haipeng Zhang Jie Tang +4 位作者 Nixi Zhao Changzhe Zhao Jianwen Wu Zhongliang Li Tiqiao Xiao 《Chinese Physics B》 2026年第1期457-465,共9页
The unique advantage of x-ray ghost imaging(XGI)is its potential in low dose radiology.One of the practical ways to reduce the radiation exposure is to reduce the measurements while remaining sufficient image quality.... The unique advantage of x-ray ghost imaging(XGI)is its potential in low dose radiology.One of the practical ways to reduce the radiation exposure is to reduce the measurements while remaining sufficient image quality.Synthetic aperture x-ray ghost imaging(SAXGI)is invented to achieve megapixel XGI with limited measurements,which is expected to implement XGI simultaneously with large field of view and low radiation exposure.In this paper,we experimentally investigate the effect of measurements reduction on the spatial resolution and image quality of SAXGI with standard sample and biomedical specimen.The results with a resolution chart demonstrated that at 360 measurements,SAXGI successfully retrieved the sample image of 1960×1960 pixels with spatial resolution of 4μm.With measurement reduction,the spatial resolution deteriorates but the sparser structures are still discernable.Even with measurements reduced to 10,a spatial resolution of 10μm can still be achieved by SAXGI.A biomedical sample of a fish specimen is employed to evaluate the method and the fish image of 2000×1000 pixels with an SSIM of 0.962 is reconstructed by SAXGI with 770measurements,corresponding to an accumulative exposure reduction of more than 2 times.With the measurements reduced to 10 which corresponds to 1/160 of the accumulative radiation exposure for conventional radiology,bulky structure like the fish skeleton can still be definitely discerned and the SSIM for the reconstructed image still retained 0.9179.Results of this paper demonstrate that measurements reduction is practicable for the radiation exposure reduction of the sample,which implicates that SAXGI with limited measurements is an efficient solution for low dose radiology. 展开更多
关键词 x-ray ghost imaging synthetic aperture x-ray imaging low dose radiology compressed sensing algorithm
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Concentrations, spatial distribution, and human exposure of synthetic phenolic antioxidants in indoor dust from ten provinces in China 被引量:1
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作者 Xueyu Weng Wanyi Wang +2 位作者 Qingqing Zhu Chunyang Liao Guibin Jiang 《Journal of Environmental Sciences》 2025年第6期584-593,共10页
Synthetic phenolic antioxidants(SPAs)are widely used in diverse industries due to their exceptional antioxidant characteristics.However,human exposure to SPAs may cause health problems.In this study,226 dust samples w... Synthetic phenolic antioxidants(SPAs)are widely used in diverse industries due to their exceptional antioxidant characteristics.However,human exposure to SPAs may cause health problems.In this study,226 dust samples were collected from 10 provinces in China,and six SPAs(three parent SPAs and their three transformation products)were analyzed.The concentrations of6SPAs(the sum of six target compounds)ranged from 15.4 to 3210 ng/g(geometric mean(GM):169 ng/g).The highest concentration of6SPAswas found in Sichuan Province(GM:349 ng/g),which was approximately 4 times higher than that in Hubei Province(81.6 ng/g)(p<0.05).The concentrations of butylated hydroxytoluene(BHT),2,2'-methylene bis(4-methyl-6–tert-butylphenol)(AO2246),2,6-di–tert–butyl–1,4-benzoquinone(BHT-Q),2,6-di–tert–butyl–4-(hydroxymethyl)phenol(BHT-OH),and ∑_(p)-SPAs were substantially higher in dust from urban areas than rural areas(p<0.05).AO2246 concentration in dust from homes(GM:0.400 ng/g)was about 4 times higher than that in workplaces(0.116 ng/g)(p<0.01).Significantly higherp-SPAs concentrations were found in dust from homes(GM:17.5 ng/g)than workplaces(11.4 ng/g)(p<0.01).The estimated daily intakes(EDIs)of ∑_(6)SPAs exposed through dust ingestion were 0.582,0.342,0.197,0.076,and 0.080 ng/kg bw/day in different age groups,and exposed through dermal contact was 0.358,0.252,0.174,0.167,and 0.177 ng/kg bw/day.EDIs showed that the exposure risks of SPAs decreased with age.This is the first work to determine SPAs in dust from10 provinces in China and investigate the spatial distribution of SPAs in those regions. 展开更多
关键词 Indoor dust synthetic phenolic antioxidants Spatial distribution Composition profile Human exposure
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Prospects for synthetic biology in 21^(st) century agriculture 被引量:1
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作者 Xingyan Ye Kezhen Qin +1 位作者 Alisdair R.Fernie Youjun Zhang 《Journal of Genetics and Genomics》 2025年第8期967-986,共20页
Plant synthetic biology has emerged as a transformative field in agriculture,offering innovative solutions to enhance food security,provide resilience to climate change,and transition to sustainable farming practices.... Plant synthetic biology has emerged as a transformative field in agriculture,offering innovative solutions to enhance food security,provide resilience to climate change,and transition to sustainable farming practices.By integrating advanced genetic tools,computational modeling,and systems biology,researchers can precisely modify plant genomes to enhance traits such as yield,stress tolerance,and nutrient use efficiency.The ability to design plants with specific characteristics tailored to diverse environmental conditions and agricultural needs holds great potential to address global food security challenges.Here,we highlight recent advancements and applications of plant synthetic biology in agriculture,focusing on key areas such as photosynthetic efficiency,nitrogen fixation,drought tolerance,pathogen resistance,nutrient use efficiency,biofortification,climate resilience,microbiology engineering,synthetic plant genomes,and the integration of artificial intelligence with synthetic biology.These innovations aim to maximize resource use efficiency,reduce reliance on external inputs,and mitigate environmental impacts associated with conventional agricultural practices.Despite challenges related to regulatory approval and public acceptance,the integration of synthetic biology in agriculture holds immense promise for creating more resilient and sustainable agricultural systems,contributing to global food security and environmental sustainability.Rigorous multi-field testing of these approaches will undoubtedly be required to ensure reproducibility. 展开更多
关键词 Plant synthetic biology PHOTOSYNTHESIS Nitrogen fixation Al integration Geneticcircuits Precision agriculture
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Advance in Sea Surface Wind and Wave Retrieval from Synthetic Aperture Radar Image:An Overview 被引量:1
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作者 HAO Mengyu HU Yuyi +3 位作者 SHAO Weizeng MIGLIACCIO Maurizio JIANG Xingwei WANG Zhenyuan 《Journal of Ocean University of China》 2025年第4期821-839,共19页
Synthetic aperture radar(SAR)aboard SEASAT was first launched in 1978.At the beginning of the 21st century,the Chinese remote sensing community recognized the urgent need to develop domestic SAR capabilities.Unlike sc... Synthetic aperture radar(SAR)aboard SEASAT was first launched in 1978.At the beginning of the 21st century,the Chinese remote sensing community recognized the urgent need to develop domestic SAR capabilities.Unlike scatterometers and al-timeters,space-borne SAR offers high-resolution images of the ocean,regardless of weather conditions or time of day.SAR imagery provides rich information about the sea surface,capturing complicated dynamic processes in the upper layers of the ocean,particular-ly in relation to tropical cyclones.Over the past four decades,the advantages of SAR have been increasingly recognized,leading to notable marine applications,especially in the development of algorithms for retrieving wind and wave data from SAR images.This study reviews the history,progress,and future outlook of SAR-based monitoring of sea surface wind and waves.In particular,the ap-plicability of various SAR wind and wave algorithms is systematically investigated,with a particular focus on their performance un-der extreme sea conditions. 展开更多
关键词 sea surface wind WAVE synthetic aperture radar tropical cyclone wave breaking
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A Novel Synthetic Process of Daprodustat
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作者 Xu Zhiyong Lin Xiaohui +3 位作者 Zhu Yuanyuan Zhang Shuangshuang Long Jiao Gu Shuangxi 《有机化学》 北大核心 2025年第9期3335-3342,共8页
An efficient and practical synthetic process for Daprodustat was developed.Starting with N,N'-dicyclohexylcarbodiimide(DCC)and malonic acid,the key intermediate 1,3-dicyclohexylpyrimidine-2,4,6(1H,3H,5H)-trione wa... An efficient and practical synthetic process for Daprodustat was developed.Starting with N,N'-dicyclohexylcarbodiimide(DCC)and malonic acid,the key intermediate 1,3-dicyclohexylpyrimidine-2,4,6(1H,3H,5H)-trione was synthesized via condensation reaction with 91%yield.Subsequent activation of this intermediate by 1,1'-carbonyldiimidazole(CDI),followed by a one-pot reaction with glycine ethyl ester hydrochloride,directly afforded Daprodustat in 92%yield with>99.8%HPLC purity.The process achieved an overall yield of 84%upon validation at 62-gram scale.Structural confirmation of the key intermediate was accomplished through nuclear magnetic resonance(NMR)spectroscopy and high-resolution mass spectrometry(HRMS).Compared with existing methods,this streamlined protocol demonstrates advantages including simplified operation,reduced reaction time,and lower production costs,offering significant potential for industrial-scale synthesis of Daprodustat. 展开更多
关键词 Daprodustat synthetic process one-pot method
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The research progress and regulation of cosmetic ingredients produced by synthetic biology at home and abroad
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作者 Yunping Lan Zhijie Xie +3 位作者 Chujie Zhao Xiaochun Liu Shiqiong Wang Qiuxing He 《日用化学工业(中英文)》 北大核心 2025年第3期367-380,共10页
The use of synthetic biology technology to develop cosmetic ingredients is attracting widespread attention due to its effectiveness,safety,and environmental friendliness.This article explains the concept of synthetic ... The use of synthetic biology technology to develop cosmetic ingredients is attracting widespread attention due to its effectiveness,safety,and environmental friendliness.This article explains the concept of synthetic biology and its key technologies and current status in the production of cosmetic ingredients.It also briefly analyzes the regulatory approaches to synthetic biology-based cosmetic ingredients in different countries and regions,providing guidance for the management of this field in China.The goal is to ensure product safety,enhance consumer trust,and promote the healthy development of the industry. 展开更多
关键词 synthetic biology cosmetic ingredients regulatory policies
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Synthetic data as an investigative tool in hypertension and renal diseases research
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作者 Aleena Jamal Som Singh Fawad Qureshi 《World Journal of Methodology》 2025年第1期9-13,共5页
There is a growing body of clinical research on the utility of synthetic data derivatives,an emerging research tool in medicine.In nephrology,clinicians can use machine learning and artificial intelligence as powerful... There is a growing body of clinical research on the utility of synthetic data derivatives,an emerging research tool in medicine.In nephrology,clinicians can use machine learning and artificial intelligence as powerful aids in their clinical decision-making while also preserving patient privacy.This is especially important given the epidemiology of chronic kidney disease,renal oncology,and hypertension worldwide.However,there remains a need to create a framework for guidance regarding how to better utilize synthetic data as a practical application in this research. 展开更多
关键词 synthetic data Artificial intelligence NEPHROLOGY Blood pressure RESEARCH EDITORIAL
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Neighbor Displacement-Based Enhanced Synthetic Oversampling for Multiclass Imbalanced Data
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作者 I Made Putrama Péter Martinek 《Computers, Materials & Continua》 2025年第6期5699-5727,共29页
Imbalanced multiclass datasets pose challenges for machine learning algorithms.They often contain minority classes that are important for accurate predictions.However,when the data is sparsely distributed and overlaps... Imbalanced multiclass datasets pose challenges for machine learning algorithms.They often contain minority classes that are important for accurate predictions.However,when the data is sparsely distributed and overlaps with data points fromother classes,it introduces noise.As a result,existing resamplingmethods may fail to preserve the original data patterns,further disrupting data quality and reducingmodel performance.This paper introduces Neighbor Displacement-based Enhanced Synthetic Oversampling(NDESO),a hybridmethod that integrates a data displacement strategy with a resampling technique to achieve data balance.It begins by computing the average distance of noisy data points to their neighbors and adjusting their positions toward the center before applying random oversampling.Extensive evaluations compare 14 alternatives on nine classifiers across synthetic and 20 real-world datasetswith varying imbalance ratios.This evaluation was structured into two distinct test groups.First,the effects of k-neighbor variations and distance metrics are evaluated,followed by a comparison of resampled data distributions against alternatives,and finally,determining the most suitable oversampling technique for data balancing.Second,the overall performance of the NDESO algorithm was assessed,focusing on G-mean and statistical significance.The results demonstrate that our method is robust to a wide range of variations in these parameters and the overall performance achieves an average G-mean score of 0.90,which is among the highest.Additionally,it attains the lowest mean rank of 2.88,indicating statistically significant improvements over existing approaches.This advantage underscores its potential for effectively handling data imbalance in practical scenarios. 展开更多
关键词 NEIGHBOR DISPLACEMENT synthetic OVERSAMPLING MULTICLASS imbalanced data
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Real-time earthquake magnitude prediction using designed machine learning ensemble trained on real and CTGAN generated synthetic data
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作者 Anushka Joshi Balasubramanian Raman C.Krishna Mohan 《Geodesy and Geodynamics》 2025年第3期350-368,共19页
The earthquake early warning(EEW)system provides advance notice of potentially damaging ground shaking.In EEW,early estimation of magnitude is crucial for timely rescue operations.A set of thirty-four features is extr... The earthquake early warning(EEW)system provides advance notice of potentially damaging ground shaking.In EEW,early estimation of magnitude is crucial for timely rescue operations.A set of thirty-four features is extracted using the primary wave earthquake precursor signal and site-specific information.In Japan's earthquake magnitude dataset,there is a chance of a high imbalance concerning the earthquakes above strong impact.This imbalance causes a high prediction error while training advanced machine learning or deep learning models.In this work,Conditional Tabular Generative Adversarial Networks(CTGAN),a deep machine learning tool,is utilized to learn the characteristics of the first arrival of earthquake P-waves and generate a synthetic dataset based on this information.The result obtained using actual and mixed(synthetic and actual)datasets will be used for training the stacked ensemble magnitude prediction model,MagPred,designed specifically for this study.There are 13295,3989,and1710 records designated for training,testing,and validation.The mean absolute error of the test dataset for single station magnitude detection using early three,four,and five seconds of P wave are 0.41,0.40,and 0.38 MJMA.The study demonstrates that the Generative Adversarial Networks(GANs)can provide a good result for single-station magnitude prediction.The study can be effective where less seismic data is available.The study shows that the machine learning method yields better magnitude detection results compared with the several regression models.The multi-station magnitude prediction study has been conducted on prominent Osaka,Off Fukushima,and Kumamoto earthquakes.Furthermore,to validate the performance of the model,an inter-region study has been performed on the earthquakes of the India or Nepal region.The study demonstrates that GANs can discover effective magnitude estimation compared with non-GAN-based methods.This has a high potential for wide application in earthquake early warning systems. 展开更多
关键词 MAGNITUDE synthetic data Machine learning EARTHQUAKE CTGAN
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Generating Synthetic Data for Machine Learning Models from the Pediatric Heart Network Fontan I Dataset
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作者 Vatche Bahudian John Valdovinos 《Congenital Heart Disease》 2025年第1期115-127,共13页
Background: The population of Fontan patients, patients born with a single functioningventricle, is growing. There is a growing need to develop algorithms for this population that can predicthealth outcomes. Artiffcia... Background: The population of Fontan patients, patients born with a single functioningventricle, is growing. There is a growing need to develop algorithms for this population that can predicthealth outcomes. Artiffcial intelligence models predicting short-term and long-term health outcomes forpatients with the Fontan circulation are needed. Generative adversarial networks (GANs) provide a solutionfor generating realistic and useful synthetic data that can be used to train such models. Methods: Despitetheir promise, GANs have not been widely adopted in the congenital heart disease research communitydue, in some part, to a lack of knowledge on how to employ them. In this research study, a GAN was usedto generate synthetic data from the Pediatric Heart Network Fontan I dataset. A subset of data consistingof the echocardiographic and BNP measures collected from Fontan patients was used to train the GAN.Two sets of synthetic data were created to understand the effect of data missingness on synthetic datageneration. Synthetic data was created from real data in which the missing values were imputed usingMultiple Imputation by Chained Equations (MICE) (referred to as synthetic from imputed real samples). Inaddition, synthetic data was created from real data in which the missing values were dropped (referred to assynthetic from dropped real samples). Both synthetic datasets were evaluated for ffdelity by using visualmethods which involved comparing histograms and principal component analysis (PCA) plots. Fidelitywas measured quantitatively by (1) comparing synthetic and real data using the Kolmogorov-Smirnovtest to evaluate the similarity between two distributions and (2) training a neural network to distinguishbetween real and synthetic samples. Both synthetic datasets were evaluated for utility by training aneural network with synthetic data and testing the neural network on its ability to classify patients thathave ventricular dysfunction using echocardiograph measures and serological measures. Results: Usinghistograms, associated probability density functions, and (PCA), both synthetic datasets showed visualresemblance in distribution and variance to real Fontan data. Quantitatively, synthetic data from droppedreal samples had higher similarity scores, as demonstrated by the Kolmogorov–Smirnov statistic, for all butone feature (age at Fontan) compared to synthetic data from imputed real samples, which demonstrateddissimilar scores for three features (Echo SV, Echo tda, and BNP). In addition, synthetic data from droppedreal samples resembled real data to a larger extent (49.3% classiffcation error) than synthetic data fromimputed real samples (65.28% classiffcation error). Classiffcation errors approximating 50% represent datasetsthat are indistinguishable. In terms of utility, synthetic data created from real data in which the missingvalues were imputed classiffed ventricular dysfunction in real data with a classiffcation error of 10.99%.Similarly, utility of the generated synthetic data by showing that a neural network trained on synthetic dataderived from real data in which the missing values were dropped could classify ventricular dysfunction inreal data with a classiffcation error of 9.44%. Conclusions: Although representing a limited subset of thevast data available on the Pediatric Heart Network, generative adversarial networks can create syntheticdata that mimics the probability distribution of real Fontan echocardiographic measures. Clinicians can usethese synthetic data to create models that predict health outcomes for Fontan patients. 展开更多
关键词 synthetic data congenital heart disease Fontan circulation
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Synthetic modeling of water distribution systems for interdependent infrastructure systems resilience analysis with interdependencies via building-mediated clustering
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作者 Yesen Yang Edmond Y.Lo 《Resilient Cities and Structures》 2025年第4期21-36,共16页
Resilience studies for water distribution systems(WDS)coupled with other interdependent infrastructure systems attract increasing attention from stakeholders and researchers.However,most existing large-scale WDS model... Resilience studies for water distribution systems(WDS)coupled with other interdependent infrastructure systems attract increasing attention from stakeholders and researchers.However,most existing large-scale WDS models are single infrastructure-based without consideration of other infrastructure systems.This is due to a lack of needed information on systems coupling,the structure of the simulator used,and the computation load involved.To address these gaps,this paper presents a synthetic modeling framework for a real-world WDS as coordinating with other infrastructure systems via a building-mediated clustering approach through consideration of physical distance and node capacity.First,the WDS network topology and operation parameters are inferred via bulk open-source information.A building-mediated clustering approach is designed to systematically derive the interdependence between the WDS and the power system similarly created as a case study.Second,a novel linearization method is developed in formulating the WDS model that can relieve computation load while maintaining accuracy.Finally,a disruption-recovery framework is developed to demonstrate the proposed methodology in modelling WDS resilience.The framework is applied to a neighborhood in Queenstown,Singapore,an area of 20.43 km^(2) and 96,000 population.The near-real-time simulations on the coupled system involving 308 nodes and 384 links showcase the effectiveness and application of the proposed synthetic modeling and formulation. 展开更多
关键词 Water distribution system Energy-water synthetic model LINEARIZATION Resilience study Interdependencies
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Occurrence and potential risks of high-molecular-weight synthetic phenolic antioxidants and long alkyl chain parabens in the Yangtze River basin, China
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作者 Zhao Tang Haifeng Zhang +3 位作者 Rongmao Wang Chunmiao Wang Yu Zhang Min Yang 《Journal of Environmental Sciences》 2025年第11期186-196,共11页
Synthetic phenolic antioxidants(SPAs)and parabens,particularly the high-molecularweight(HMW)SPAs and long alkyl chain(LAC)parabens with higher environmental persistence and toxicities,are widely produced and applied w... Synthetic phenolic antioxidants(SPAs)and parabens,particularly the high-molecularweight(HMW)SPAs and long alkyl chain(LAC)parabens with higher environmental persistence and toxicities,are widely produced and applied worldwide.However,their occurrence and potential risks in aquatic environments remain largely unknown.This work investigated 11 HMW SPAs and 3 LAC parabens in the river and treated industrial wastewater samples along the Yangtze River,the largest river and most important source water in China.For convenience of comparison,6 short alkyl chain(SAC)parabens were also included.In 15 industrial wastewater treatment plant effluents(effluent-IWTPs)and 34 surface water monitoring sections along the river,19 out of 20 target compounds were detected with total concentrations(TCs)from 152.5 to 1955.5 ng/L and 141.3 to 1364.9 ng/L in effluent-IWTPs and surface water,respectively.HMW SPAs 1,3,5-tris-[(3,5-di–tert–butyl–4-hydroxyphenyl)methyl]-1,3,5-triazinane-2,4,6-trione(AO3114)and octadecyl 3-(3,5-di–tert–butyl–4-hydroxyphenyl)propionate(AO1076)were the dominant ones.HMWSPAs bis(3–tert–butyl–4–hydroxy-5-methylphenyl)propionate(AO245)and 4,4'-sulfanediylbis(2–tert–butyl–5-methylphenol)(AO-TBM6)and SAC parabens propylparaben(PrP)and butylparaben(BuP)posed medium to high potential ecological risks in 27 surface water monitoring sections.Additionally,AO-TBM6 also exhibited potential health risks in 2 out of 11 drinking water sources.Though the ecotoxicity data are very limited,the ubiquitous presence of the LAC parabens including hexylparaben(HeP)and octylparaben(OcP)in surface water should be of concern since these compounds usually exhibit stronger estrogen potencies than the SAC ones.Finally,kernel density analysis revealed that regulation of industrial discharges is necessary to mitigate the HMW SPA and paraben contamination. 展开更多
关键词 synthetic antioxidant PARABEN Yangtze River Risk Industrial discharge
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Interlayer exchange coupling effects on the spin-orbit torque in synthetic magnets
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作者 Haodong Fan Zhongshu Feng +11 位作者 Tingwei Chen Xiaofeng Han Xinyu Shu Mingzhang Wei Shiqi Liu Mengxi Wang Shengru Chen Xuejian Tang Menghao Jin Yungui Ma Bo Liu Tiejun Zhou 《Chinese Physics B》 2025年第9期654-661,共8页
Interlayer exchange coupling(IEC)plays a critical role in spin-orbit torque(SOT)switching in synthetic magnets.This work establishes a fundamental correlation between IEC and SOT dynamics within Co/Pt-based synthetic ... Interlayer exchange coupling(IEC)plays a critical role in spin-orbit torque(SOT)switching in synthetic magnets.This work establishes a fundamental correlation between IEC and SOT dynamics within Co/Pt-based synthetic antiferromagnets and synthetic ferromagnets.The antiferromagnetic and ferromagnetic coupling states are precisely engineered through Ruderman-Kittel-Kasuya-Yosida(RKKY)interactions by modulating the Ir spacer thickness.Experimental results reveal that the critical switching current density exhibits a strong positive correlation with the IEC strength,regardless of the coupling type.A comprehensive theoretical framework based on the Landau-Lifshitz-Gilbert equation elucidates how IEC contributes to the effective energy barrier that must be overcome during SOT-induced magnetization switching.Significantly,the antiferromagnetically coupled samples demonstrate enhanced SOT efficiency,with the spin Hall angle being directly proportional to the antiferromagnetic exchange coupling field.These insights establish a coherent physical paradigm for understanding IEC-dependent SOT dynamics and provide strategic design principles for the development of energy-efficient next-generation spintronic devices. 展开更多
关键词 interlayer exchange coupling spin-orbit torque synthetic antiferromagnet
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A simulation and experimental study of a valveless piezoelectric micropump based on the synthetic jet principle
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作者 Wencheng Lv Jiafeng Ni +6 位作者 Weipeng Xuan Yixing Li Xiwei Huang Lingling Sun Hao Jin Shurong Dong Jikui Luo 《Nanotechnology and Precision Engineering》 2025年第2期86-94,共9页
A stacked piezoelectric micropump based on the synthetic jet principle with a size of 22×22×5 mm^(3) is designed and fabricated.Through theoretical and finite element method(FEM)analysis,the conditions for a... A stacked piezoelectric micropump based on the synthetic jet principle with a size of 22×22×5 mm^(3) is designed and fabricated.Through theoretical and finite element method(FEM)analysis,the conditions for achieving a synthetic jet structure are obtained,and the gas flow properties inside the chamber are analyzed.The first-order mode and resonant frequency of the piezoelectric actuator are simulated.At a resonant frequency of 22.5 kHz,the maximum central displacement of the actuator can reach 12.3μm.In addition,the key dimensions of the micropump are optimized to improve the output flow rate.Experiments on the prototype of the micropump show that it can reach a maximum output flow rate of 618 mL/min when driven by a sine wave signal of 42 Vpp and 22.5 kHz.The power dissipation does not exceed 600 mW. 展开更多
关键词 Piezoelectric actuator Piezoelectric valveless pump synthetic jet principle
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Analysis of Azimuthal Cutoff Wavelength Derived from Sentinel-1 Synthetic Aperture Radar Image in Tropical Cyclones
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作者 HU Yuyi SHAO Weizeng +2 位作者 MARINO Armando JIANG Xingwei WANG Zhenyuan 《Journal of Ocean University of China》 2025年第5期1169-1181,共13页
The purpose of this study is to analyze the impact of upper ocean dynamics on velocity bunching,represented by az-imuthal cutoff wavelength(i.e.,sea surface wind,wave,and current).In this study,over 1400 dual-polarize... The purpose of this study is to analyze the impact of upper ocean dynamics on velocity bunching,represented by az-imuthal cutoff wavelength(i.e.,sea surface wind,wave,and current).In this study,over 1400 dual-polarized(vertical-vertical(VV)and vertical-horizontal(VH))Sentinel-1(S-1)synthetic aperture radar(SAR)images collected in tropical cyclones(TC)are utilized.These images are combined with wind and rain observations from the stepped-frequency microwave radiometer(SFMR),wave simu-lations conducted using a third-generation numerical wave model,WAVEWATCH-III(WW3),and SAR-derived wind information collected from CyclObs winds.The WW3-simulated significant wave height(SWH)is validated against measurements from HY-2B altimeter taken in August and September 2021,yielding a root mean square error(RMSE)of 0.48 m and a correlation coefficient(COR)of 0.88.The SAR-based azimuthal cutoff wavelengths in VV polarization,which quantitatively represent the effect of velocity bunching,are compared with theoretical values calculated using WW3-simulated SWH.A notable relationship is observed between the difference in azimuthal cutoff wavelength and SAR-derived wind speed and WW3-simulated SWH.Analysis results show that the correlation between SAR-based azimuthal cutoff wavelength and SWH is stronger than that with wind and current.Finally,a machine learning algorithm is used to develop an algorithm aimed at simulating the azimuthal cutoff wavelength in TCs,including wind,wave,and incidence angle.This method yields an RMSE of 8.90 m,a COR of 0.91,and a scatter index of 0.04 for VV-polar-ization SAR. 展开更多
关键词 azimuthal cutoff wavelength synthetic aperture radar tropical cyclones
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Prospects of synthetic biology in revolutionizing microbial synthesis and drug discovery
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作者 Emmanuel Chimeh Ezeako Abel Yashim Solomon +7 位作者 Yemiode Bernard Itam Tobechukwu Christian Ezike Chinenye Peace Ogbonna Nnamdi Ginikachukwu Amuzie Emmanuel Chigozie Aham Cynthia Doowuese Aondover Gloria Oluchukwu Osuagwu Vincent Eric Ozougwu 《Life Research》 2025年第1期51-60,共10页
Synthetic biology(SynBio)is an emerging field of study with great potential in designing,engineering,and constructing new microbial synthetic cells that do not pre-exist in nature or re-engineering existing cells to a... Synthetic biology(SynBio)is an emerging field of study with great potential in designing,engineering,and constructing new microbial synthetic cells that do not pre-exist in nature or re-engineering existing cells to accomplish industrial purposes.Systems biology seeks to understand biology at multiple dimensions,beginning with the molecular and cellular level and progressing to the tissues and organismal level and characterizes cells as complex information-processing systems.SynBio,on the other hand,toggles further and strives to develop and create its systems from scratch.SynBio is now applied in the development of novel therapeutic drugs for the prevention of human diseases,scale up industrial processes,and accomplish previously unfeasible industrial outcomes.This is made possible through significant breakthroughs in DNA sequencing and synthesis technology,as well as insights gained from synthetic chemistry and systems biology.SynBio technologies have allowed for the introduction of improved and synthetic metabolic functionalities in microorganisms to enable the synthesis of a range of pharmacologically-relevant compounds for pharmaceutical exploration.SynBio applications range from finding new ways to making industrial chemical synthesis processes more sustainable as well as the microbial synthesis of improved therapeutic modalities.Hence,this study underpins several innovations,auspicious potentials,and future directions afforded by SynBio that proposes improved industrial microbial synthesis for pharmaceutical exploration. 展开更多
关键词 synthetic biology drug discovery microbial synthesis sustainable development genetic circuit gene editing
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The Predictive Value of Combined Synthetic MRI Features and PSAD for Clinically Significant Prostate Cancer
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作者 Yunqi Yang Yukang Hu Chunhua Xia 《Journal of Clinical and Nursing Research》 2025年第12期223-230,共8页
Objective:To investigate the diagnostic and predictive value of MRI features combined with clinical indicators for prostate cancer(PCa)and clinically significant prostate cancer(csPCa),and to establish a non-invasive ... Objective:To investigate the diagnostic and predictive value of MRI features combined with clinical indicators for prostate cancer(PCa)and clinically significant prostate cancer(csPCa),and to establish a non-invasive combined model.Methods:A total of 36 patients with pathologically confirmed benign lesions(44 foci)and 23 patients with PCa(49 foci),including 25 foci of csPCa and 68 foci of non-csPCa,were included.SyMRI quantitative maps and clinical indicators were collected,and 224 imaging features were extracted.The intra-and inter-group correlation coefficients(ICC)for each feature were calculated using intra-and inter-group correlation analysis,and features with an ICC>0.75 were selected as stable features that could be reproducibly extracted.Independent predictors were screened using logistic regression to construct single and combined models,and the performance was evaluated using ROC curves.Results:Age,PSAD,PD map contrast,and T2 map joint entropy were significantly higher in the PCa group compared to the benign group,while the median ADC was significantly lower(p<0.05).The above-mentioned indicators were significantly correlated with PCa and csPCa,and the diagnostic performance of the combined model was superior to that of a single MRI or clinical model.Conclusion:MRI features combined with PSAD can effectively differentiate PCa and predict csPCa,providing a non-invasive quantitative diagnostic basis for clinical practice. 展开更多
关键词 Prostate cancer Prostate-specific antigen synthetic magnetic resonance imaging Predictive value
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A step towards understanding plastic complexity:Antimony speciation in consumer plastics and synthetic textiles revealed by XAS
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作者 Camelia N.Borca Thomas Huthwelker Montserrat Filella 《Journal of Environmental Sciences》 2025年第7期109-117,共9页
We identified the antimony species present in a wide variety of plastic samples by X ray absorption spectroscopy(XAS)at the Sb L_(3)-edge.The samples contained different concentrations of antimony(Sb),ranging from PET... We identified the antimony species present in a wide variety of plastic samples by X ray absorption spectroscopy(XAS)at the Sb L_(3)-edge.The samples contained different concentrations of antimony(Sb),ranging from PET bottles in which Sb compounds are used as catalysts,with concentrations around 300 mg/kg,to electrical equipment in which the element is used as a flame retardant,with concentrations of several tens of thousands of mg/kg.Although the shape of the spectra at the L_(3)-edge is quite similar for all Sb reference materials,we were able to identify antimony glycolate or acetate in PET bottles,bound organic Sb in c-PET trays and senarmontite in electrical materials as themain Sb components.In samples with high Ca content(e.g.,electrical objects,some c-PET food trays and textiles)the Ca Ka emission line interferes with the Sb La line by introducing a high background which reduces the signal-to-noise ratio in the Sb XAS spectrum,resulting in noisy and distorted spectra.The element-resolved map on a PET bottle sample revealed both Sb and Ca hot spots of around 10-20 microns in size,with no correlation. 展开更多
关键词 ANTIMONY PLASTICS Sb L_(3)-edge Senarmontite synthetic textiles
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Novel control method of vortex breakdown over delta wing using dual synthetic jets
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作者 Hao WANG Zhenbing LUO +3 位作者 Xiong DENG Yan ZHOU Zhijie ZHAO Jianyuan ZHANG 《Chinese Journal of Aeronautics》 2025年第5期52-64,共13页
To delay the vortex breakdown position of the slender delta wing,this study innovativelyproposes the application of control near the Leading-Edge Vortex(LEV)core sweeping path,whichis called Coupled Core Rotation Dual... To delay the vortex breakdown position of the slender delta wing,this study innovativelyproposes the application of control near the Leading-Edge Vortex(LEV)core sweeping path,whichis called Coupled Core Rotation Dual Synthetic Jets(CCR-DSJ)control.The results show that thevortex breakdown points at each angle of attack are moved backward after control,and the max-imum delayed displacement is 32.4%of the root chord at 30°.Besides,there is a linear relationshipbetween the breakdown position and the angle of attack after control,indicating that CCR-DSJcontrol has a significant effect on the pressure gradient of the vortex axis.Furthermore,the lift coef-ficient C_(L)is enhanced after control,with a maximum CLincrement of 0.078 at 27°,and an effectiveincrement interval of[25°,32°].This interval is different from most previous studies,which isdirectly related to the position of the actuators.According to the lift change mechanism,the anglesof attack are divided into three stages:Stage 1(a=15°–25°),Stage 2(a=25°–32°),and Stage 3(a=32°–40°).In conclusion,CCR-DSJ control can significantly change the pressure distribution,thereby offering promising prospects for the flight stage of the slender delta wing. 展开更多
关键词 Vortex breakdown Delta wing Vortex core Core rotation Dual synthetic jets
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