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Ground-based and additional science support for SMILE 被引量:2
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作者 J.A.Carter M.Dunlop +46 位作者 C.Forsyth K.Oksavik E.Donovon A.Kavanagh S.E.Milan T.Sergienko R.C.Fear D.G.Sibeck M.Connors T.Yeoman X.Tan M.G.G.T.Taylor K.McWilliams J.Gjerloev R.Barnes D.D.Billet G.Chisham A.Dimmock M.P.Freeman D.-S.Han M.D.Hartinger S.-Y.W.Hsieh Z.-J.Hu M.K.James L.Juusola K.Kauristie E.A.Kronberg M.Lester J.Manuel J.Matzka I.McCrea Y.Miyoshi J.Rae L.Ren F.Sigernes E.Spanswick K.Sterne A.Steuwer T.Sun M.-T.Walach B.Walsh C.Wang J.Weygand J.Wild J.Yan J.Zhang Q.-H.Zhang 《Earth and Planetary Physics》 EI CSCD 2024年第1期275-298,共24页
The joint European Space Agency and Chinese Academy of Sciences Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will explore global dynamics of the magnetosphere under varying solar wind and interplane... The joint European Space Agency and Chinese Academy of Sciences Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will explore global dynamics of the magnetosphere under varying solar wind and interplanetary magnetic field conditions,and simultaneously monitor the auroral response of the Northern Hemisphere ionosphere.Combining these large-scale responses with medium and fine-scale measurements at a variety of cadences by additional ground-based and space-based instruments will enable a much greater scientific impact beyond the original goals of the SMILE mission.Here,we describe current community efforts to prepare for SMILE,and the benefits and context various experiments that have explicitly expressed support for SMILE can offer.A dedicated group of international scientists representing many different experiment types and geographical locations,the Ground-based and Additional Science Working Group,is facilitating these efforts.Preparations include constructing an online SMILE Data Fusion Facility,the discussion of particular or special modes for experiments such as coherent and incoherent scatter radar,and the consideration of particular observing strategies and spacecraft conjunctions.We anticipate growing interest and community engagement with the SMILE mission,and we welcome novel ideas and insights from the solar-terrestrial community. 展开更多
关键词 MAGNETOSPHERE IONOSPHERE magnetosphere-ionosphere coupling ground-based experimentation SMILE CONJUNCTIONS MISSIONS
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Ground-Based Atmospheric CO_(2),CH_(4),and CO Column Measurements at Golmud in the Qinghai-Tibetan Plateau and Comparisons with TROPOMI/S5P Satellite Observations 被引量:2
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作者 Minqiang ZHOU Qichen NI +7 位作者 Zhaonan CAI Bavo LANGEROCK Jingyi JIANG Ke CHE Jiaxin WANG Weidong NAN Yi LIU Pucai WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第2期223-234,共12页
Measurements of carbon dioxide(CO_(2)),methane(CH_(4)),and carbon monoxide(CO)are of great importance in the Qinghai-Tibetan region,as it is the highest and largest plateau in the world affecting global weather and cl... Measurements of carbon dioxide(CO_(2)),methane(CH_(4)),and carbon monoxide(CO)are of great importance in the Qinghai-Tibetan region,as it is the highest and largest plateau in the world affecting global weather and climate systems.In this study,for the first time,we present CO_(2),CH_(4),and CO column measurements carried out by a Bruker EM27/SUN Fourier-transform infrared spectrometer(FTIR)at Golmud(36.42°E,94.91°N,2808 m)in August 2021.The mean and standard deviation of the column-average dry-air mixing ratio of CO_(2),CH_(4),and CO(XCO_(2),XCH_(4),and XCO)are 409.3±0.4 ppm,1905.5±19.4 ppb,and 103.1±7.7 ppb,respectively.The differences between the FTIR co-located TROPOMI/S5P satellite measurements at Golmud are 0.68±0.64%(13.1±12.2 ppb)for XCH_(4) and 9.81±3.48%(–10.7±3.8 ppb)for XCO,which are within their retrieval uncertainties.High correlations for both XCH_(4) and XCO are observed between the FTIR and S5P satellite measurements.Using the FLEXPART model and satellite measurements,we find that enhanced CH_(4) and CO columns in Golmud are affected by anthropogenic emissions transported from North India.This study provides an insight into the variations of the CO_(2),CH_(4),and CO columns in the Qinghai-Tibetan Plateau. 展开更多
关键词 ground-based FTIR greenhouse gas remote sensing TROPOMI/S5P Qinghai-Tibetan Plateau
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Modeling and Analysis of the Impacts of Temporal-Spatial Variant Troposphere on Ground-Based SAR Imaging of Asteroids
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作者 Tingting Fu Yuanhao Li +2 位作者 Zhiyang Chen Zheng Wu Cheng Hu 《Journal of Beijing Institute of Technology》 EI CAS 2023年第6期727-739,共13页
The near-Earth asteroid collisions could cause catastrophic disasters to humanity and the Earth,so it is crucial to monitor asteroids.Ground-based synthetic aperture radar(SAR)is an observation technique for high reso... The near-Earth asteroid collisions could cause catastrophic disasters to humanity and the Earth,so it is crucial to monitor asteroids.Ground-based synthetic aperture radar(SAR)is an observation technique for high resolution imaging of asteroids.The ground-based SAR requires a long integration time to achieve a large synthetic aperture,and the echo signal will be seriously affected by temporal-spatial variant troposphere.Traditional spatiotemporal freezing tropospheric models are ineffective.To cope with this,this paper models and analyses the impacts of temporal-spatial variant troposphere on ground-based SAR imaging of asteroids.For the background tropo-sphere,a temporal-spatial variant ray tracing method is proposed to trace the 4D(3D spatial+temporal)refractive index network provided by the numerical weather model,and calculate the error of the background troposphere.For the tropospheric turbulence,the Andrew power spectral model is used in conjunction with multiphase screen theory,and varying errors are obtained by tracking the changing position of the pierce point on the phase screen.Through simulation,the impact of temporal-spatial variant tropospheric errors on image quality is analyzed,and the simulation results show that the X-band echo signal is seriously affected by the troposphere and the echo signal must be compensated. 展开更多
关键词 near-Earth asteroids ground-based SAR troposphere ray tracing
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Perpendicular-Cutdepth:Perpendicular Direction Depth Cutting Data Augmentation Method
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作者 Le Zou Linsong Hu +2 位作者 Yifan Wang Zhize Wu Xiaofeng Wang 《Computers, Materials & Continua》 SCIE EI 2024年第4期927-941,共15页
Depth estimation is an important task in computer vision.Collecting data at scale for monocular depth estimation is challenging,as this task requires simultaneously capturing RGB images and depth information.Therefore... Depth estimation is an important task in computer vision.Collecting data at scale for monocular depth estimation is challenging,as this task requires simultaneously capturing RGB images and depth information.Therefore,data augmentation is crucial for this task.Existing data augmentationmethods often employ pixel-wise transformations,whichmay inadvertently disrupt edge features.In this paper,we propose a data augmentationmethod formonocular depth estimation,which we refer to as the Perpendicular-Cutdepth method.This method involves cutting realworld depth maps along perpendicular directions and pasting them onto input images,thereby diversifying the data without compromising edge features.To validate the effectiveness of the algorithm,we compared it with existing convolutional neural network(CNN)against the current mainstream data augmentation algorithms.Additionally,to verify the algorithm’s applicability to Transformer networks,we designed an encoder-decoder network structure based on Transformer to assess the generalization of our proposed algorithm.Experimental results demonstrate that,in the field of monocular depth estimation,our proposed method,Perpendicular-Cutdepth,outperforms traditional data augmentationmethods.On the indoor dataset NYU,our method increases accuracy from0.900 to 0.907 and reduces the error rate from0.357 to 0.351.On the outdoor dataset KITTI,our method improves accuracy from 0.9638 to 0.9642 and decreases the error rate from 0.060 to 0.0598. 展开更多
关键词 PERPENDICULAR depth estimation data augmentation
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Enhanced prediction of anisotropic deformation behavior using machine learning with data augmentation
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作者 Sujeong Byun Jinyeong Yu +3 位作者 Seho Cheon Seong Ho Lee Sung Hyuk Park Taekyung Lee 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期186-196,共11页
Mg alloys possess an inherent plastic anisotropy owing to the selective activation of deformation mechanisms depending on the loading condition.This characteristic results in a diverse range of flow curves that vary w... Mg alloys possess an inherent plastic anisotropy owing to the selective activation of deformation mechanisms depending on the loading condition.This characteristic results in a diverse range of flow curves that vary with a deformation condition.This study proposes a novel approach for accurately predicting an anisotropic deformation behavior of wrought Mg alloys using machine learning(ML)with data augmentation.The developed model combines four key strategies from data science:learning the entire flow curves,generative adversarial networks(GAN),algorithm-driven hyperparameter tuning,and gated recurrent unit(GRU)architecture.The proposed model,namely GAN-aided GRU,was extensively evaluated for various predictive scenarios,such as interpolation,extrapolation,and a limited dataset size.The model exhibited significant predictability and improved generalizability for estimating the anisotropic compressive behavior of ZK60 Mg alloys under 11 annealing conditions and for three loading directions.The GAN-aided GRU results were superior to those of previous ML models and constitutive equations.The superior performance was attributed to hyperparameter optimization,GAN-based data augmentation,and the inherent predictivity of the GRU for extrapolation.As a first attempt to employ ML techniques other than artificial neural networks,this study proposes a novel perspective on predicting the anisotropic deformation behaviors of wrought Mg alloys. 展开更多
关键词 Plastic anisotropy Compression ANNEALING Machine learning Data augmentation
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Image segmentation of exfoliated two-dimensional materials by generative adversarial network-based data augmentation
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作者 程晓昱 解晨雪 +6 位作者 刘宇伦 白瑞雪 肖南海 任琰博 张喜林 马惠 蒋崇云 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期112-117,共6页
Mechanically cleaved two-dimensional materials are random in size and thickness.Recognizing atomically thin flakes by human experts is inefficient and unsuitable for scalable production.Deep learning algorithms have b... Mechanically cleaved two-dimensional materials are random in size and thickness.Recognizing atomically thin flakes by human experts is inefficient and unsuitable for scalable production.Deep learning algorithms have been adopted as an alternative,nevertheless a major challenge is a lack of sufficient actual training images.Here we report the generation of synthetic two-dimensional materials images using StyleGAN3 to complement the dataset.DeepLabv3Plus network is trained with the synthetic images which reduces overfitting and improves recognition accuracy to over 90%.A semi-supervisory technique for labeling images is introduced to reduce manual efforts.The sharper edges recognized by this method facilitate material stacking with precise edge alignment,which benefits exploring novel properties of layered-material devices that crucially depend on the interlayer twist-angle.This feasible and efficient method allows for the rapid and high-quality manufacturing of atomically thin materials and devices. 展开更多
关键词 two-dimensional materials deep learning data augmentation generating adversarial networks
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Investigation of Inside-Out Tracking Methods for Six Degrees of Freedom Pose Estimation of a Smartphone in Augmented Reality
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作者 Chanho Park Takefumi Ogawa 《Computers, Materials & Continua》 SCIE EI 2024年第5期3047-3065,共19页
Six degrees of freedom(6DoF)input interfaces are essential formanipulating virtual objects through translation or rotation in three-dimensional(3D)space.A traditional outside-in tracking controller requires the instal... Six degrees of freedom(6DoF)input interfaces are essential formanipulating virtual objects through translation or rotation in three-dimensional(3D)space.A traditional outside-in tracking controller requires the installation of expensive hardware in advance.While inside-out tracking controllers have been proposed,they often suffer from limitations such as interaction limited to the tracking range of the sensor(e.g.,a sensor on the head-mounted display(HMD))or the need for pose value modification to function as an input interface(e.g.,a sensor on the controller).This study investigates 6DoF pose estimation methods without restricting the tracking range,using a smartphone as a controller in augmented reality(AR)environments.Our approach involves proposing methods for estimating the initial pose of the controller and correcting the pose using an inside-out tracking approach.In addition,seven pose estimation algorithms were presented as candidates depending on the tracking range of the device sensor,the tracking method(e.g.,marker recognition,visual-inertial odometry(VIO)),and whether modification of the initial pose is necessary.Through two experiments(discrete and continuous data),the performance of the algorithms was evaluated.The results demonstrate enhanced final pose accuracy achieved by correcting the initial pose.Furthermore,the importance of selecting the tracking algorithm based on the tracking range of the devices and the actual input value of the 3D interaction was emphasized. 展开更多
关键词 SMARTPHONE inside-out tracking 6DoF pose 3D interaction augmented reality
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Defect Detection Model Using Time Series Data Augmentation and Transformation
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作者 Gyu-Il Kim Hyun Yoo +1 位作者 Han-Jin Cho Kyungyong Chung 《Computers, Materials & Continua》 SCIE EI 2024年第2期1713-1730,共18页
Time-series data provide important information in many fields,and their processing and analysis have been the focus of much research.However,detecting anomalies is very difficult due to data imbalance,temporal depende... Time-series data provide important information in many fields,and their processing and analysis have been the focus of much research.However,detecting anomalies is very difficult due to data imbalance,temporal dependence,and noise.Therefore,methodologies for data augmentation and conversion of time series data into images for analysis have been studied.This paper proposes a fault detection model that uses time series data augmentation and transformation to address the problems of data imbalance,temporal dependence,and robustness to noise.The method of data augmentation is set as the addition of noise.It involves adding Gaussian noise,with the noise level set to 0.002,to maximize the generalization performance of the model.In addition,we use the Markov Transition Field(MTF)method to effectively visualize the dynamic transitions of the data while converting the time series data into images.It enables the identification of patterns in time series data and assists in capturing the sequential dependencies of the data.For anomaly detection,the PatchCore model is applied to show excellent performance,and the detected anomaly areas are represented as heat maps.It allows for the detection of anomalies,and by applying an anomaly map to the original image,it is possible to capture the areas where anomalies occur.The performance evaluation shows that both F1-score and Accuracy are high when time series data is converted to images.Additionally,when processed as images rather than as time series data,there was a significant reduction in both the size of the data and the training time.The proposed method can provide an important springboard for research in the field of anomaly detection using time series data.Besides,it helps solve problems such as analyzing complex patterns in data lightweight. 展开更多
关键词 Defect detection time series deep learning data augmentation data transformation
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Leveraging Augmented Reality,Semantic-Segmentation,and VANETs for Enhanced Driver’s Safety Assistance
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作者 Sitara Afzal Imran Ullah Khan +1 位作者 Irfan Mehmood Jong Weon Lee 《Computers, Materials & Continua》 SCIE EI 2024年第1期1443-1460,共18页
Overtaking is a crucial maneuver in road transportation that requires a clear view of the road ahead.However,limited visibility of ahead vehicles can often make it challenging for drivers to assess the safety of overt... Overtaking is a crucial maneuver in road transportation that requires a clear view of the road ahead.However,limited visibility of ahead vehicles can often make it challenging for drivers to assess the safety of overtaking maneuvers,leading to accidents and fatalities.In this paper,we consider atrous convolution,a powerful tool for explicitly adjusting the field-of-view of a filter as well as controlling the resolution of feature responses generated by Deep Convolutional Neural Networks in the context of semantic image segmentation.This article explores the potential of seeing-through vehicles as a solution to enhance overtaking safety.See-through vehicles leverage advanced technologies such as cameras,sensors,and displays to provide drivers with a real-time view of the vehicle ahead,including the areas hidden from their direct line of sight.To address the problems of safe passing and occlusion by huge vehicles,we designed a see-through vehicle system in this study,we employed a windshield display in the back car together with cameras in both cars.The server within the back car was used to segment the car,and the segmented portion of the car displayed the video from the front car.Our see-through system improves the driver’s field of vision and helps him change lanes,cross a large car that is blocking their view,and safely overtake other vehicles.Our network was trained and tested on the Cityscape dataset using semantic segmentation.This transparent technique will instruct the driver on the concealed traffic situation that the front vehicle has obscured.For our findings,we have achieved 97.1% F1-score.The article also discusses the challenges and opportunities of implementing see-through vehicles in real-world scenarios,including technical,regulatory,and user acceptance factors. 展开更多
关键词 Overtaking safety augmented reality VANET V2V deep learning
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YOLO-Based Damage Detection with StyleGAN3 Data Augmentation for Parcel Information-Recognition System
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作者 Seolhee Kim Sang-Duck Lee 《Computers, Materials & Continua》 SCIE EI 2024年第7期195-215,共21页
Damage to parcels reduces customer satisfactionwith delivery services and increases return-logistics costs.This can be prevented by detecting and addressing the damage before the parcels reach the customer.Consequentl... Damage to parcels reduces customer satisfactionwith delivery services and increases return-logistics costs.This can be prevented by detecting and addressing the damage before the parcels reach the customer.Consequently,various studies have been conducted on deep learning techniques related to the detection of parcel damage.This study proposes a deep learning-based damage detectionmethod for various types of parcels.Themethod is intended to be part of a parcel information-recognition systemthat identifies the volume and shipping information of parcels,and determines whether they are damaged;this method is intended for use in the actual parcel-transportation process.For this purpose,1)the study acquired image data in an environment simulating the actual parcel-transportation process,and 2)the training dataset was expanded based on StyleGAN3 with adaptive discriminator augmentation.Additionally,3)a preliminary distinction was made between the appearance of parcels and their damage status to enhance the performance of the parcel damage detection model and analyze the causes of parcel damage.Finally,using the dataset constructed based on the proposed method,a damage type detection model was trained,and its mean average precision was confirmed.This model can improve customer satisfaction and reduce return costs for parcel delivery companies. 展开更多
关键词 Parcel delivery service damage detection damage classification data augmentation generative adversarial network
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Single-center experience with Knee+^(TM) augmented reality navigation system in primary total knee arthroplasty
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作者 Evangelos Sakellariou Panagiotis Alevrogiannis +6 位作者 Fani Alevrogianni Athanasios Galanis Michail Vavourakis Panagiotis Karampinas Panagiotis Gavriil John Vlamis Stavros Alevrogiannis 《World Journal of Orthopedics》 2024年第3期247-256,共10页
BACKGROUND Computer-assisted systems obtained an increased interest in orthopaedic surgery over the last years,as they enhance precision compared to conventional hardware.The expansion of computer assistance is evolvi... BACKGROUND Computer-assisted systems obtained an increased interest in orthopaedic surgery over the last years,as they enhance precision compared to conventional hardware.The expansion of computer assistance is evolving with the employment of augmented reality.Yet,the accuracy of augmented reality navigation systems has not been determined.AIM To examine the accuracy of component alignment and restoration of the affected limb’s mechanical axis in primary total knee arthroplasty(TKA),utilizing an augmented reality navigation system and to assess whether such systems are conspicuously fruitful for an accomplished knee surgeon.METHODS From May 2021 to December 2021,30 patients,25 women and five men,under-went a primary unilateral TKA.Revision cases were excluded.A preoperative radiographic procedure was performed to evaluate the limb’s axial alignment.All patients were operated on by the same team,without a tourniquet,utilizing three distinct prostheses with the assistance of the Knee+™augmented reality navigation system in every operation.Postoperatively,the same radiographic exam protocol was executed to evaluate the implants’position,orientation and coronal plane alignment.We recorded measurements in 3 stages regarding femoral varus and flexion,tibial varus and posterior slope.Firstly,the expected values from the Augmented Reality system were documented.Then we calculated the same values after each cut and finally,the same measurements were recorded radiolo-gically after the operations.Concerning statistical analysis,Lin’s concordance correlation coefficient was estimated,while Wilcoxon Signed Rank Test was performed when needed.RESULTS A statistically significant difference was observed regarding mean expected values and radiographic mea-surements for femoral flexion measurements only(Z score=2.67,P value=0.01).Nonetheless,this difference was statistically significantly lower than 1 degree(Z score=-4.21,P value<0.01).In terms of discrepancies in the calculations of expected values and controlled measurements,a statistically significant difference between tibial varus values was detected(Z score=-2.33,P value=0.02),which was also statistically significantly lower than 1 degree(Z score=-4.99,P value<0.01).CONCLUSION The results indicate satisfactory postoperative coronal alignment without outliers across all three different implants utilized.Augmented reality navigation systems can bolster orthopaedic surgeons’accuracy in achieving precise axial alignment.However,further research is required to further evaluate their efficacy and potential. 展开更多
关键词 augmented reality ORTHOPEDICS Total knee arthroplasty ROBOTICS KNEE NAVIGATION
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Large-scale spatial data visualization method based on augmented reality
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作者 Xiaoning QIAO Wenming XIE +4 位作者 Xiaodong PENG Guangyun LI Dalin LI Yingyi GUO Jingyi REN 《虚拟现实与智能硬件(中英文)》 EI 2024年第2期132-147,共16页
Background A task assigned to space exploration satellites involves detecting the physical environment within a certain space.However,space detection data are complex and abstract.These data are not conducive for rese... Background A task assigned to space exploration satellites involves detecting the physical environment within a certain space.However,space detection data are complex and abstract.These data are not conducive for researchers'visual perceptions of the evolution and interaction of events in the space environment.Methods A time-series dynamic data sampling method for large-scale space was proposed for sample detection data in space and time,and the corresponding relationships between data location features and other attribute features were established.A tone-mapping method based on statistical histogram equalization was proposed and applied to the final attribute feature data.The visualization process is optimized for rendering by merging materials,reducing the number of patches,and performing other operations.Results The results of sampling,feature extraction,and uniform visualization of the detection data of complex types,long duration spans,and uneven spatial distributions were obtained.The real-time visualization of large-scale spatial structures using augmented reality devices,particularly low-performance devices,was also investigated.Conclusions The proposed visualization system can reconstruct the three-dimensional structure of a large-scale space,express the structure and changes in the spatial environment using augmented reality,and assist in intuitively discovering spatial environmental events and evolutionary rules. 展开更多
关键词 Large-scale spatial data analysis Visual analysis technology augmented reality 3D reconstruction Space environment
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Change in self-image pressure level before and after autologous fat breast augmentation and its effect on social adaptability
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作者 Jian Li Hui-Min Wang +2 位作者 Yang Jiang Zhen-Nan Liu Bai-Hui He 《World Journal of Psychiatry》 SCIE 2024年第6期920-929,共10页
BACKGROUND There is an increasingly strong demand for appearance and physical beauty in social life,marriage,and other aspects with the development of society and the improvement of material living standards.An increa... BACKGROUND There is an increasingly strong demand for appearance and physical beauty in social life,marriage,and other aspects with the development of society and the improvement of material living standards.An increasing number of people have improved their appearance and physical shape through aesthetic plastic surgery.The female breast plays a significant role in physical beauty,and droopy or atrophied breasts can frequently lead to psychological inferiority and lack of confidence in women.This,in turn,can affect their mental health and quality of life.AIM To analyze preoperative and postoperative self-image pressure-level changes of autologous fat breast augmentation patients and their impact on social adaptability.METHODS We selected 160 patients who underwent autologous fat breast augmentation at the First Affiliated Hospital of Xinxiang Medical University from January 2020 to December 2022 using random sampling method.The general information,selfimage pressure level,and social adaptability of the patients were investigated using a basic information survey,body image self-assessment scale,and social adaptability scale.The self-image pressure-level changes and their effects on the social adaptability of patients before and after autologous fat breast augmentation were analyzed.RESULTS We collected 142 valid questionnaires.The single-factor analysis results showed no statistically significant difference in the self-image pressure level and social adaptability score of patients with different ages,marital status,and monthly income.However,there were significant differences in social adaptability among patients with different education levels and employment statuses.The correlation analysis results revealed a significant correlation between the self-image pressure level and social adaptability score before and after surgery.Multiple factors analysis results showed that the degree of concern caused by appearance in selfimage pressure,the degree of possible behavioral intervention,the related distress caused by body image,and the influence of body image on social life influenced the social adaptability of autologous fat breast augmentation patients.CONCLUSION The self-image pressure on autologous fat breast augmentation patients is inversely proportional to their social adaptability. 展开更多
关键词 Autologous fat breast augmentation surgery Self-image stress level Social adaptability Analysis of correlation Structural equation model
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Transcranial direct current stimulation as early augmentation in adolescent obsessive compulsive disorder:A pilot proof-of-concept randomized control trial
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作者 Aditya Agrawal Vivek Agarwal +1 位作者 Sujita Kumar Kar Amit Arya 《World Journal of Clinical Pediatrics》 2024年第2期161-170,共10页
BACKGROUND Transcranial direct current stimulation(tDCS)is proven to be safe in treating various neurological conditions in children and adolescents.It is also an effective method in the treatment of OCD in adults.AIM... BACKGROUND Transcranial direct current stimulation(tDCS)is proven to be safe in treating various neurological conditions in children and adolescents.It is also an effective method in the treatment of OCD in adults.AIM To assess the safety and efficacy of tDCS as an add-on therapy in drug-naive adolescents with OCD.METHODS We studied drug-naïve adolescents with OCD,using a Children’s Yale-Brown obsessive-compulsive scale(CY-BOCS)scale to assess their condition.Both active and sham groups were given fluoxetine,and we applied cathode and anode over the supplementary motor area and deltoid for 20 min in 10 sessions.Reassessment occurred at 2,6,and 12 wk using CY-BOCS.RESULTS Eighteen adolescents completed the study(10-active,8-sham group).CY-BOCS scores from baseline to 12 wk reduced significantly in both groups but change at baseline to 2 wk was significant in the active group only.The mean change at 2 wk was more in the active group(11.8±7.77 vs 5.25±2.22,P=0.056).Adverse effects between the groups were comparable.CONCLUSION tDCS is safe and well tolerated for the treatment of OCD in adolescents.However,there is a need for further studies with a larger sample population to confirm the effectiveness of tDCS as early augmentation in OCD in this population. 展开更多
关键词 Adolescents Early augmentation Obsessive compulsive disorder SAFETY Transcranial direct current stimulation
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基于Swin Transformer网络与Adapt-RandAugment数据增强方法的小肠胶囊内镜图像分类方法研究
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作者 聂瑞 刘学思 +5 位作者 童飞 邓远阳 刘相花 杨利 张和华 段傲文 《医疗卫生装备》 CAS 2024年第6期9-16,共8页
目的:为提高小肠病变分类识别的准确性,提出一种基于Swin Transformer网络与Adapt-RandAugment数据增强方法的小肠胶囊内镜图像分类方法。方法:基于RandAugment数据增强子策略和增强小肠胶囊内镜图像时不丢失特征、不失真的原则提出Adap... 目的:为提高小肠病变分类识别的准确性,提出一种基于Swin Transformer网络与Adapt-RandAugment数据增强方法的小肠胶囊内镜图像分类方法。方法:基于RandAugment数据增强子策略和增强小肠胶囊内镜图像时不丢失特征、不失真的原则提出Adapt-RandAugment数据增强方法。在公开的小肠胶囊内镜图像Kvasir-Capsule数据集中,基于Swin Transformer网络,采用Adapt-RandAugment数据增强方法进行训练,以卷积神经网络ResNet152、DenseNet161为基准,验证Swin Transformer网络和Adapt-RandAugment数据增强方法组合对小肠胶囊内镜图像分类识别的性能。结果:提出的方法宏平均精度(macro average precision,MAC-PRE)、宏平均召回率(macro average recall,MAC-REC)、宏F1分数(macro average F1 score,MAC-F1-S)分别为0.3832、0.3148、0.2905,微平均精度(micro average precision,MIC-PRE)、微平均召回率(micro average recall,MIC-REC)、微平均F1分数(micro average F1 score,MIC-F1-S)均为0.7553,马修斯相关系数(Matthews correlation coefficient,MCC)为0.4523,均优于ResNet152和DenseNet161网络。结论:基于Swin Transformer网络与Adapt-RandAugment数据增强方法的小肠胶囊内镜图像分类方法具有较好的小肠胶囊内镜图像分类识别效果和较高的识别准确率。 展开更多
关键词 Swin Transformer网络 Adapt-Randaugment 数据增强 胶囊内镜 图像分类 小肠病变
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Long-term gravity changes in Chinese mainland from GRACE and ground-based gravity measurements 被引量:3
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作者 Xing Lelin Li Hui +2 位作者 Xuan Songbai Kang Kaixuan Liu Xiaoling 《Geodesy and Geodynamics》 2011年第3期61-70,共10页
A long-term (9 years) gravity change in Chinese mainland is obtained on the basis of observation of the ground-based national gravity network. The result shows several features that may be related to sore, large-sca... A long-term (9 years) gravity change in Chinese mainland is obtained on the basis of observation of the ground-based national gravity network. The result shows several features that may be related to sore, large-scale groundwater pumping in North China, glacier-water flow and storage in Tianshan region, and pre seismic gravity changes of the 2008 MsS. 0 Wenchuan earthquake, which are spatially similar to co-seismi, changes but reversed in sign. These features are also shown in the result of the satellite-based GRACE obser vation, after a height effect is corrected with GPS data. 展开更多
关键词 GRACE ground-based gravity measurement mass distribution EARTHQUAKE
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An approach to wide-field imaging of linear rail ground-based SAR in high squint multi-angle mode 被引量:2
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作者 ZHANG Yuan ZHANG Qiming +4 位作者 WANG Yanping LIN Yun LI Yang BAI Zechao LI Fang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第4期722-733,共12页
Ground-based synthetic aperture radar(GB-SAR) has been successfully applied to the ground deformation monitoring.However, due to the short length of the GB-SAR platform, the scope of observation is largely limited. Th... Ground-based synthetic aperture radar(GB-SAR) has been successfully applied to the ground deformation monitoring.However, due to the short length of the GB-SAR platform, the scope of observation is largely limited. The practical applications drive us to make improvements on the conventional linear rail GB-SAR system in order to achieve larger field imaging. First, a turntable is utilized to support the rotational movement of the radar.Next, a series of high-squint scanning is performed with multiple squint angles. Further, the high squint modulation phase of the echo data is eliminated. Then, a new multi-angle imaging method is performed in the wave number domain to expand the field of view. Simulation and real experiments verify the effectiveness of this method. 展开更多
关键词 ground-based synthetic aperture radar(GB-SAR) high squint multi-angle
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0-10 KM TEMPERATURE AND HUMIDITY PROFILES RETRIEVAL FROM GROUND-BASED MICROWAVE RADIOMETER 被引量:2
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作者 鲍艳松 蔡僖 +3 位作者 钱程 闵锦忠 陆其峰 左泉 《Journal of Tropical Meteorology》 SCIE 2018年第2期243-252,共10页
Deviation exists between measured and simulated microwave radiometer sounding data. The bias results in low-accuracy atmospheric temperature and humidity profiles simulated by Back Propagation artificial neural networ... Deviation exists between measured and simulated microwave radiometer sounding data. The bias results in low-accuracy atmospheric temperature and humidity profiles simulated by Back Propagation artificial neural network models. This paper evaluated a retrieving atmospheric temperature and humidity profiles method by adopting an input data adjustment-based Back Propagation artificial neural networks model. First, the sounding data acquired at a Nanjing meteorological site in June 2014 were inputted into the Mono RTM Radiative transfer model to simulate atmospheric downwelling radiance at the 22 spectral channels from 22.234 GHz to 58.8 GHz, and we performed a comparison and analysis of the real observed data; an adjustment model for the measured microwave radiometer sounding data was built. Second, we simulated the sounding data of the 22 channels using the sounding data acquired at the site from 2011 to 2013. Based on the simulated rightness temperature data and the sounding data, BP neural network-based models were trained for the retrieval of atmospheric temperature, water vapor density and relative humidity profiles. Finally, we applied the adjustment model to the microwave radiometer sounding data collected in July 2014, generating the corrected data. After that, we inputted the corrected data into the BP neural network regression model to predict the atmospheric temperature, vapor density and relative humidity profile at 58 high levels from 0 to 10 km. We evaluated our model's effect by comparing its output with the real measured data and the microwave radiometer's own second-level product. The experiments showed that the inversion model improves atmospheric temperature and humidity profile retrieval accuracy; the atmospheric temperature RMS error is between 1 K and 2.0 K; the water vapor density's RMS error is between 0.2 g/m^3 and 1.93 g/m3; and the relative humidity's RMS error is between 2.5% and 18.6%. 展开更多
关键词 ground-based microwave radiometer BP neural network atmospheric profiles regression accuracy
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Seismic Noise Suppression for Ground-Based Investigation of an Inertial Sensor by Suspending the Electrode Cage 被引量:3
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作者 谭定银 尹航 周泽兵 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第9期9-12,共4页
Performance test of a high precise accelerometer or an inertial sensor on the ground is inevitably limited by the seismic noise. A torsion pendulum has been used to investigate the performances of an electrostatic acc... Performance test of a high precise accelerometer or an inertial sensor on the ground is inevitably limited by the seismic noise. A torsion pendulum has been used to investigate the performances of an electrostatic accelerometer, where the test mass is suspended by a fiber to compensate for its weight, and this scheme demonstrates an advantage, compared with the high-voltage levitation scheme, in which the effect of the seismic noise can be suppressed for a few orders of magnitude in low frequencies. In this work, the capacitive electrode cage is proposed to be suspended by another pendulum, and theoretical analysis shows that the effects of the seismic noise can be further suppressed for more than one order by suspending the electrode cage. 展开更多
关键词 LENGTH Seismic Noise Suppression for ground-based Investigation of an Inertial Sensor by Suspending the Electrode Cage
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Ground-based GPS Used in the Snow Depth Survey of Greenland 被引量:3
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作者 Shuangcheng ZHANG Meiling ZHOU +3 位作者 Yajie WANG Ning LIU Qi LIU Jilun PENG 《Journal of Geodesy and Geoinformation Science》 2021年第2期47-55,共9页
Snow cover is one of the important components of land cover,and it is necessary to accurately monitor the depth and coverage of snow cover.Using the GPS signal receiver data and the basic principle of snow depth detec... Snow cover is one of the important components of land cover,and it is necessary to accurately monitor the depth and coverage of snow cover.Using the GPS signal receiver data and the basic principle of snow depth detection based on GPS-MR technology,the snow depth of the three sites on the Greenland PBO network GLS1,GLS2,and GLS3 from 2012 to 2018 was obtained.The inversion snow depth is affected by site drift,which is a quite difference from the measured snow depth.Combined with the stable reference point,the velocity field distribution of Greenland Island and the U-direction component change value of the station can be obtained through GAMIT calculation.By analyzing the glacial flow and U-direction component,the influence of the site drift on the snow depth was deducted,and finally compared the corrected inversion snow depth and measured snow depth found that the two were better than before the correction,the results were significantly improved,and the consistency was good.The analysis of the experimental results showed that in extremely cold areas such as Greenland Island,affected by glaciers,the continuous,real-time,high-time resolution snow depth around the measured station obtained by ground-based GPS tracking stations has a large gap with the measured snow depth value,and the gap will gradually increase with time.By deducting the impact of glacier drift,the trend of the two is the same and the consistency is good.The correctness and feasibility of the application of ground-based GPS snow cover theory in the polar area further expand the application scope and practical value of ground-based GPS in snow monitoring. 展开更多
关键词 ground-based GPS GREENLAND GPS-MR snow depth time series
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