BACKGROUND: No retrievable and repositionable second generation transcatheter aortic valve is available in China. Here, we report the first-in-man implantation of the retrievable and repositionable VenusA-Plus valve. ...BACKGROUND: No retrievable and repositionable second generation transcatheter aortic valve is available in China. Here, we report the first-in-man implantation of the retrievable and repositionable VenusA-Plus valve. METHODS: A 76-year-old patient with symptomatic severe aortic stenosis and high surgical risk(STS 13.8%) was recommended for transcatheter aortic valve replacement(TAVR) by heart valve team. Type 0 bicuspid aortic valve with asymmetric calcification was identified by dual source computed tomography, and the unfavorable anatomies increased the possibility of malposition and paravalvular leakage during TAVR. Therefore, we used the retrievable and repositionable Venus APlus valve for the patient.RESULTS: Transfemoral TAVR was performed under local anesthesia with sedation, and a 26-mm VenusA-Plus valve was successfully implanted. No transvalvular pressure gradient and trace paravalvular leakage were found. CONCLUSION: The successful first-in-man implantation indicates the retrievable and repositionable Venus A-Plus valve is feasible in complicated TAVR cases such as bicuspid aortic valve.展开更多
BACKGROUND Endoscopic ultrasound-guided gastroenterostomy(EUS-GE)is an alternative method for the surgical treatment of gastric outlet obstruction,but it is regarded as a challenging technique for endoscopists as the ...BACKGROUND Endoscopic ultrasound-guided gastroenterostomy(EUS-GE)is an alternative method for the surgical treatment of gastric outlet obstruction,but it is regarded as a challenging technique for endoscopists as the bowel is highly mobile and can tent away.Thus,the technique requires superb skill.In order to improve EUS-GE,we have developed a retrievable puncture anchor traction(RPAT)device for EUSGE to address the issue of bowel tenting.AIM To evaluate the feasibility of RPAT-assisted EUS-GE using an animal model.METHODS Six Bama mini pigs each weighing between 15 and 20 kg underwent the RPATassisted EUS-GE procedure.Care was taken to ensure that the animals experienced minimal pain and discomfort.Two days prior to the procedure the animals were limited to a liquid diet.No oral intake was allowed on the day before the procedure.A fully covered metal stent was placed between the stomach and the intestine using the RPAT-assisted EUS-GE method.Infection in the animals was determined.Four weeks after the procedure,a standard gastroscope was inserted into the pig’s intestine through a previously created fistula in order to check the status of the stents under anesthesia.The pig was euthanized after examination.RESULTS The RPAT-assisted EUS-GE method allowed placement of the stents with no complications in all six animals.All the pigs tolerated a regular diet within hours of the procedure.The animals were monitored for four weeks after the RPATassisted EUS-GE,during which time all of the animals exhibited normal eating behavior and no signs of infection were observed.Endoscopic imaging performed four weeks after the RPAT-assisted EUS-GE showed that the stents remained patent and stable in all the animals.No tissue overgrowth or ingrowth was observed in any case.Each animal had a mature fistula,and the stents were removed without significant bleeding.Autopsies of all six pigs revealed complete adhesion between the intestine and the stomach wall.CONCLUSION The RPAT method helps reduce mobility of the bowel.Therefore,the RPATassisted EUS-GE method is a minimally invasive treatment modality.展开更多
With the increasing popularity of cloud computing,privacy has become one of the key problem in cloud security.When data is outsourced to the cloud,for data owners,they need to ensure the security of their privacy;for ...With the increasing popularity of cloud computing,privacy has become one of the key problem in cloud security.When data is outsourced to the cloud,for data owners,they need to ensure the security of their privacy;for cloud service providers,they need some information of the data to provide high QoS services;and for authorized users,they need to access to the true value of data.The existing privacy-preserving methods can't meet all the needs of the three parties at the same time.To address this issue,we propose a retrievable data perturbation method and use it in the privacy-preserving in data outsourcing in cloud computing.Our scheme comes in four steps.Firstly,an improved random generator is proposed to generate an accurate "noise".Next,a perturbation algorithm is introduced to add noise to the original data.By doing this,the privacy information is hidden,but the mean and covariance of data which the service providers may need remain unchanged.Then,a retrieval algorithm is proposed to get the original data back from the perturbed data.Finally,we combine the retrievable perturbation with the access control process to ensure only the authorized users can retrieve the original data.The experiments show that our scheme perturbs date correctly,efficiently,and securely.展开更多
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
Pill image recognition is an important field in computer vision.It has become a vital technology in healthcare and pharmaceuticals due to the necessity for precise medication identification to prevent errors and ensur...Pill image recognition is an important field in computer vision.It has become a vital technology in healthcare and pharmaceuticals due to the necessity for precise medication identification to prevent errors and ensure patient safety.This survey examines the current state of pill image recognition,focusing on advancements,methodologies,and the challenges that remain unresolved.It provides a comprehensive overview of traditional image processing-based,machine learning-based,deep learning-based,and hybrid-based methods,and aims to explore the ongoing difficulties in the field.We summarize and classify the methods used in each article,compare the strengths and weaknesses of traditional image processing-based,machine learning-based,deep learning-based,and hybrid-based methods,and review benchmark datasets for pill image recognition.Additionally,we compare the performance of proposed methods on popular benchmark datasets.This survey applies recent advancements,such as Transformer models and cutting-edge technologies like Augmented Reality(AR),to discuss potential research directions and conclude the review.By offering a holistic perspective,this paper aims to serve as a valuable resource for researchers and practitioners striving to advance the field of pill image recognition.展开更多
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
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
Background:Testicular sperm aspiration(TESA)is a minimally invasive testicular sperm retrieval technique that has been utilized in the treatment of male factor infertility.We sought to evaluate sperm retrieval outcome...Background:Testicular sperm aspiration(TESA)is a minimally invasive testicular sperm retrieval technique that has been utilized in the treatment of male factor infertility.We sought to evaluate sperm retrieval outcomes of primary and redo TESA in men with severe oligoasthenoteratozoospermia(OAT)and obstructive azoospermia(OA).Methods:This is a retrospective analysis of consecutive TESAs(primary and redo)for men with severe OAT and OA performed between January 2011 and August 2022 at a high-volume infertility center.We compared TESA outcomes in men with severe OAT to those with OA and compared outcomes of men who underwent primary and redo TESA on the same testicular unit.Results:439 TESAs(366 primary and 73 redo)in men with severe OAT(n=133)and OA(n=306)were included.Men with OA had significantly higher sperm retrieval rate(SRR)and motile SRR compared to men with severe OAT(99%vs.95%and 98%vs.83%,respectively,p<0.05).The requirement for multiple biopsies and the total number of aspirates were significantly lower in men with OA compared to those with severe OAT(15%vs.32%and 1.2±0.5 vs.1.4±0.7,respectively,p<0.05).In both groups,SRR,motile SRR,the requirement for multiple biopsies,and the total number of aspirates were not significantly different in primary compared to redo cases.Conclusion:Our data demonstrate that TESA retrieval rates are significantly higher in men with OA compared to those with severe OAT.The data also demonstrate that a redo TESA in these men is as effective as a primary TESA,suggesting that areas of active spermatogenesis are preserved 6 months after TESA.展开更多
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
Reliable surface height observations over inland water bodies are useful for understanding the hydrological cycle.Satellite radar altimetry particularly contributed with its long-term archive and minimal cloud interfe...Reliable surface height observations over inland water bodies are useful for understanding the hydrological cycle.Satellite radar altimetry particularly contributed with its long-term archive and minimal cloud interference.Specialized inland water altimetry,developed from oceanography and geodesy,is still being extensively investigated.By synthesizing pioneering studies on“retracking algorithms”,this review demonstrates,from a user perspective,why optimizing conventional retracking is still important and how it can extend reliable historical water level retrieval over more ungauged sites.Numerous unrevealed inland water bodies have small sizes or complex surroundings,posing challenges to maintaining accuracy.Applications have shown that a critical key lies in the retracking correction during range retrieval(uncertainty likely on the order of meters),compared with other corrections(on the order of centimeters or decimeters).From multiple uncertainty factors in range retrieval,signal entanglements from land contamination and off-nadir effects are core issues.We evaluate and compared key strategies from prototype retrackers to improved retrackers,especially the empirical ones optimized for inland waters.Sub-waveform extraction and adjustment for Delay-Doppler modes has advanced range retrieval to a new stage.Four innovative inland-water-compatible retrackers are introduced in detail,with a highlight on their distinct approaches to robustly improve performance.Considering the selection of different data and retrackers in varying scenarios,a synthesis analysis is conducted based on results reported in previous literature.In conclusion,the empirical retracking has been enhanced to offer stable decimeter-level accuracy in intricate landscapes(e.g.,small lakes and rivers with varied surroundings).In comparison,the physical retracking has been upgraded to provide greater precision for homogeneous surface in large lakes.For future inland water altimetry,we articulate how additionally retracked results can benefit hydrological applications,and what difficulties would arise when extending study scales.展开更多
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
In global navigation satellite system denial environment,cross-view geo-localization based on image retrieval presents an exceedingly critical visual localization solution for Unmanned Aerial Vehicle(UAV)systems.The e...In global navigation satellite system denial environment,cross-view geo-localization based on image retrieval presents an exceedingly critical visual localization solution for Unmanned Aerial Vehicle(UAV)systems.The essence of cross-view geo-localization resides in matching images containing the same geographical targets from disparate platforms,such as UAV-view and satellite-view images.However,images of the same geographical targets may suffer from occlusions and geometric distortions due to variations in the capturing platform,view,and timing.The existing methods predominantly extract features by segmenting feature maps,which overlook the holistic semantic distribution and structural information of objects,resulting in loss of image information.To address these challenges,dilated neighborhood attention Transformer is employed as the feature extraction backbone,and Multi-feature representations based on Multi-scale Hierarchical Contextual Aggregation(MMHCA)is proposed.In the proposed MMHCA method,the multiscale hierarchical contextual aggregation method is utilized to extract contextual information from local to global across various granularity levels,establishing feature associations of contextual information with global and local information in the image.Subsequently,the multi-feature representations method is utilized to obtain rich discriminative feature information,bolstering the robustness of model in scenarios characterized by positional shifts,varying distances,and scale ambiguities.Comprehensive experiments conducted on the extensively utilized University-1652 and SUES-200 benchmarks indicate that the MMHCA method surpasses the existing techniques.showing outstanding results in UAV localization and navigation.展开更多
To investigate the impact of preoperative serum follicle-stimulating hormone(FSH)levels on the probability of testicular sperm retrieval,we conducted a study of nonobstructive azoospermic(NOA)men with different testic...To investigate the impact of preoperative serum follicle-stimulating hormone(FSH)levels on the probability of testicular sperm retrieval,we conducted a study of nonobstructive azoospermic(NOA)men with different testicular volumes(TVs)who underwent microdissection testicular sperm extraction(micro-TESE).A total of 177 NOA patients undergoing micro-TESE for the first time from April 2019 to November 2022 in Shenzhen Zhongshan Obstetrics and Gynecology Hospital(formerly Shenzhen Zhongshan Urology Hospital,Shenzhen,China)were retrospectively reviewed.The subjects were divided into four groups based on average TV quartiles.Serum hormone levels in each TV group were compared between positive and negative sperm retrieval subgroups.Overall sperm retrieval rate was 57.6%.FSH levels(median[interquartile range])were higher in the positive sperm retrieval subgroup compared with the negative outcome subgroup when average TV was<5 ml(first quartile[Q1:TV<3 ml]:43.32[17.92]IU l^(−1) vs 32.95[18.56]IU l−1,P=0.048;second quartile[Q2:3 ml≤TV<5 ml]:31.31[15.37]IU l^(−1) vs 25.59[18.40]IU l^(−1),P=0.042).Elevated serum FSH levels were associated with successful micro-TESE sperm retrieval in NOA men whose average TVs were<5 ml(adjusted odds ratio[OR]:1.06 per unit increase;95%confidence interval[CI]:1.01–1.11;P=0.011).In men with TVs≥5 ml,larger TVs were associated with lower odds of sperm retrieval(adjusted OR:0.84 per 1 ml increase;95%CI:0.71–0.98;P=0.029).In conclusion,elevated serum FSH levels were associated with positive sperm retrieval in micro-TESE in NOA men with TVs<5 ml.In men with TV≥5 ml,increases in average TVs were associated with lower odds of sperm retrieval.展开更多
Mixed-phase clouds(MPCs)involve complex microphysical and dynamical processes of cloud formation and dissipation,which are crucial for numerical weather prediction and cloud-climate feedback.However,satellite remote s...Mixed-phase clouds(MPCs)involve complex microphysical and dynamical processes of cloud formation and dissipation,which are crucial for numerical weather prediction and cloud-climate feedback.However,satellite remote sensing of MPC properties is still challenging,and there is seldom MPC result inferred from passive spectral observations.This study examines the spectral characteristics of MPCs in the shortwave-infrared(SWIR)channels over the wavelength of 0.4–2.5μm,and evaluates the potential of current operational satellite spectroradiometer channels for MPC retrievals.With optical properties of MPCs based on the assumption of uniform mixing of both ice and liquid water particles,the effects of MPC ice optical thickness fraction(IOTF)and effective radius on associated optical properties are analyzed.As expected,results indicate that the MPC optical properties show features for ice and liquid water clouds,and their spectral variations show noticeable differences from those for homogeneous cases.A radiative transfer method is employed to examine the sensitivity of SWIR channels to given MPC cloud water path(CWP)and IOTF.MPCs have unique signal characteristics in the SWIR spectrum.The 0.87-μm channel is most sensitive to CWP.Meanwhile,the 1.61-and 2.13-μm channels are more sensitive to water-dominated MPCs(IOTF approaching 0),and the 2.25-μm channel is sensitive to both water-dominated and ice-dominated MPCs(IOTF approaching 1).Such spectral differences are potentially possible to be used to infer MPC properties based on radiometer observations,which will be investigated in future studies.展开更多
Aerosol optical depth(AOD)and fine particulate matter with a diameter of less than or equal to 2.5μm(PM_(2.5))play crucial roles in air quality,human health,and climate change.However,the complex correlation of AOD–...Aerosol optical depth(AOD)and fine particulate matter with a diameter of less than or equal to 2.5μm(PM_(2.5))play crucial roles in air quality,human health,and climate change.However,the complex correlation of AOD–PM_(2.5)and the limitations of existing algorithms pose a significant challenge in realizing the accurate joint retrieval of these two parameters at the same location.On this point,a multi-task learning(MTL)model,which enables the joint retrieval of PM_(2.5)concentration and AOD,is proposed and applied on the top-of-the-atmosphere reflectance data gathered by the Fengyun-4A Advanced Geosynchronous Radiation Imager(FY-4A AGRI),and compared to that of two single-task learning models—namely,Random Forest(RF)and Deep Neural Network(DNN).Specifically,MTL achieves a coefficient of determination(R^(2))of 0.88 and a root-mean-square error(RMSE)of 0.10 in AOD retrieval.In comparison to RF,the R^(2)increases by 0.04,the RMSE decreases by 0.02,and the percentage of retrieval results falling within the expected error range(Within-EE)rises by 5.55%.The R^(2)and RMSE of PM_(2.5)retrieval by MTL are 0.84 and 13.76μg m~(-3)respectively.Compared with RF,the R^(2)increases by 0.06,the RMSE decreases by 4.55μg m~(-3),and the Within-EE increases by 7.28%.Additionally,compared to DNN,MTL shows an increase of 0.01 in R^(2)and a decrease of 0.02 in RMSE in AOD retrieval,with a corresponding increase of 2.89%in Within-EE.For PM_(2.5)retrieval,MTL exhibits an increase of 0.05 in R^(2),a decrease of 1.76μg m~(-3)in RMSE,and an increase of 6.83%in Within-EE.The evaluation suggests that MTL is able to provide simultaneously improved AOD and PM_(2.5)retrievals,demonstrating a significant advantage in efficiently capturing the spatial distribution of PM_(2.5)concentration and AOD.展开更多
Infertility,defined as the inability to conceive after 1 year of regular unprotected intercourse,impacts 10%–20%of couples globally.Both male and female factors contribute equally to this condition.Azoospermia,partic...Infertility,defined as the inability to conceive after 1 year of regular unprotected intercourse,impacts 10%–20%of couples globally.Both male and female factors contribute equally to this condition.Azoospermia,particularly nonobstructive azoospermia(NOA),which affects 10%–15%of infertile men,represents a significant challenge in male infertility.The advent of assisted reproductive technology(ART),specifically microdissection testicular sperm extraction(micro-TESE)followed by intracytoplasmic sperm injection(ICSI),offers a possibility for men with NOA to father biological children.Recent studies have focused on the predictors of sperm retrieval in NOA patients,such as age,testicular volume,and follicle-stimulating hormone(FSH)level.This review aims to explore the limited data on the anatomical characteristics of NOA patients and provide surgical considerations for micro-TESE,thereby enhancing understanding and improving outcomes for this challenging condition.展开更多
Indoor visual localization relies heavily on image retrieval to ascertain location information.However,the widespread presence and high consistency of floor patterns across different images of-ten lead to the extracti...Indoor visual localization relies heavily on image retrieval to ascertain location information.However,the widespread presence and high consistency of floor patterns across different images of-ten lead to the extraction of numerous repetitive features,thereby reducing the accuracy of image retrieval.This article proposes an indoor visual localization method based on semantic segmentation and adaptive weight fusion to address the issue of ground texture interference with retrieval results.During the positioning process,an indoor semantic segmentation model is established.Semantic segmentation technology is applied to accurately delineate the ground portion of the images.Fea-ture extraction is performed on both the original database and the ground-segmented database.The vector of locally aggregated descriptors(VLAD)algorithm is then used to convert image features into a fixed-length feature representation,which improves the efficiency of image retrieval.Simul-taneously,a method for adaptive weight optimization in similarity calculation is proposed,using a-daptive weights to compute similarity for different regional features,thereby improving the accuracy of image retrieval.The experimental results indicate that this method significantly reduces ground interference and effectively utilizes ground information,thereby improving the accuracy of image retrieval.展开更多
1 The need to refine journal subject classification systems Journal subject classification systems are fundamental to journal evaluation,research assessments and information retrieval.Previous studies(e.g.,Wang&Wa...1 The need to refine journal subject classification systems Journal subject classification systems are fundamental to journal evaluation,research assessments and information retrieval.Previous studies(e.g.,Wang&Waltman,2016)have identified accuracy issues in major classification systems such as the Subject Categories in the Web of Science and ASJC in Scopus.展开更多
Speech-face association aims to achieve identity matching between facial images and voice segments by aligning cross-modal features.Existing research primarily focuses on learning shared-space representations and comp...Speech-face association aims to achieve identity matching between facial images and voice segments by aligning cross-modal features.Existing research primarily focuses on learning shared-space representations and computing one-to-one similarities between cross-modal sample pairs to establish their correlation.However,these approaches do not fully account for intra-class variations between the modalities or the many-to-many relationships among cross-modal samples,which are crucial for robust association modeling.To address these challenges,we propose a novel framework that leverages global information to align voice and face embeddings while effectively correlating identity information embedded in both modalities.First,we jointly pre-train face recognition and speaker recognition networks to encode discriminative features from facial images and voice segments.This shared pre-training step ensures the extraction of complementary identity information across modalities.Subsequently,we introduce a cross-modal simplex center loss,which aligns samples with identity centers located at the vertices of a regular simplex inscribed on a hypersphere.This design enforces an equidistant and balanced distribution of identity embeddings,reducing intra-class variations.Furthermore,we employ an improved triplet center loss that emphasizes hard sample mining and optimizes inter-class separability,enhancing the model’s ability to generalize across challenging scenarios.Extensive experiments validate the effectiveness of our framework,demonstrating superior performance across various speech-face association tasks,including matching,verification,and retrieval.Notably,in the challenging gender-constrained matching task,our method achieves a remarkable accuracy of 79.22%,significantly outperforming existing approaches.These results highlight the potential of the proposed framework to advance the state of the art in cross-modal identity association.展开更多
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
基金supported by Advanced Technique Research of Valvular Heart Disease Treatment Project(2015C03028)
文摘BACKGROUND: No retrievable and repositionable second generation transcatheter aortic valve is available in China. Here, we report the first-in-man implantation of the retrievable and repositionable VenusA-Plus valve. METHODS: A 76-year-old patient with symptomatic severe aortic stenosis and high surgical risk(STS 13.8%) was recommended for transcatheter aortic valve replacement(TAVR) by heart valve team. Type 0 bicuspid aortic valve with asymmetric calcification was identified by dual source computed tomography, and the unfavorable anatomies increased the possibility of malposition and paravalvular leakage during TAVR. Therefore, we used the retrievable and repositionable Venus APlus valve for the patient.RESULTS: Transfemoral TAVR was performed under local anesthesia with sedation, and a 26-mm VenusA-Plus valve was successfully implanted. No transvalvular pressure gradient and trace paravalvular leakage were found. CONCLUSION: The successful first-in-man implantation indicates the retrievable and repositionable Venus A-Plus valve is feasible in complicated TAVR cases such as bicuspid aortic valve.
基金Supported by the China Postdoctoral Science Foundation,No.2019M661174National Natural Science Foundation of China,No.81770655the Natural Science Foundation of Liaoning Province,No.2019-MS-359.
文摘BACKGROUND Endoscopic ultrasound-guided gastroenterostomy(EUS-GE)is an alternative method for the surgical treatment of gastric outlet obstruction,but it is regarded as a challenging technique for endoscopists as the bowel is highly mobile and can tent away.Thus,the technique requires superb skill.In order to improve EUS-GE,we have developed a retrievable puncture anchor traction(RPAT)device for EUSGE to address the issue of bowel tenting.AIM To evaluate the feasibility of RPAT-assisted EUS-GE using an animal model.METHODS Six Bama mini pigs each weighing between 15 and 20 kg underwent the RPATassisted EUS-GE procedure.Care was taken to ensure that the animals experienced minimal pain and discomfort.Two days prior to the procedure the animals were limited to a liquid diet.No oral intake was allowed on the day before the procedure.A fully covered metal stent was placed between the stomach and the intestine using the RPAT-assisted EUS-GE method.Infection in the animals was determined.Four weeks after the procedure,a standard gastroscope was inserted into the pig’s intestine through a previously created fistula in order to check the status of the stents under anesthesia.The pig was euthanized after examination.RESULTS The RPAT-assisted EUS-GE method allowed placement of the stents with no complications in all six animals.All the pigs tolerated a regular diet within hours of the procedure.The animals were monitored for four weeks after the RPATassisted EUS-GE,during which time all of the animals exhibited normal eating behavior and no signs of infection were observed.Endoscopic imaging performed four weeks after the RPAT-assisted EUS-GE showed that the stents remained patent and stable in all the animals.No tissue overgrowth or ingrowth was observed in any case.Each animal had a mature fistula,and the stents were removed without significant bleeding.Autopsies of all six pigs revealed complete adhesion between the intestine and the stomach wall.CONCLUSION The RPAT method helps reduce mobility of the bowel.Therefore,the RPATassisted EUS-GE method is a minimally invasive treatment modality.
基金supported in part by NSFC under Grant No.61172090National Science and Technology Major Project under Grant 2012ZX03002001+3 种基金Research Fund for the Doctoral Program of Higher Education of China under Grant No.20120201110013Scientific and Technological Project in Shaanxi Province under Grant(No.2012K06-30, No.2014JQ8322)Basic Science Research Fund in Xi'an Jiaotong University(No. XJJ2014049,No.XKJC2014008)Shaanxi Science and Technology Innovation Project (2013SZS16-Z01/P01/K01)
文摘With the increasing popularity of cloud computing,privacy has become one of the key problem in cloud security.When data is outsourced to the cloud,for data owners,they need to ensure the security of their privacy;for cloud service providers,they need some information of the data to provide high QoS services;and for authorized users,they need to access to the true value of data.The existing privacy-preserving methods can't meet all the needs of the three parties at the same time.To address this issue,we propose a retrievable data perturbation method and use it in the privacy-preserving in data outsourcing in cloud computing.Our scheme comes in four steps.Firstly,an improved random generator is proposed to generate an accurate "noise".Next,a perturbation algorithm is introduced to add noise to the original data.By doing this,the privacy information is hidden,but the mean and covariance of data which the service providers may need remain unchanged.Then,a retrieval algorithm is proposed to get the original data back from the perturbed data.Finally,we combine the retrievable perturbation with the access control process to ensure only the authorized users can retrieve the original data.The experiments show that our scheme perturbs date correctly,efficiently,and securely.
基金funded by the Institute of InformationTechnology,VietnamAcademy of Science and Technology(project number CSCL02.02/22-23)“Research and Development of Methods for Searching Similar Trademark Images Using Machine Learning to Support Trademark Examination in Vietnam”.
文摘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.
文摘Pill image recognition is an important field in computer vision.It has become a vital technology in healthcare and pharmaceuticals due to the necessity for precise medication identification to prevent errors and ensure patient safety.This survey examines the current state of pill image recognition,focusing on advancements,methodologies,and the challenges that remain unresolved.It provides a comprehensive overview of traditional image processing-based,machine learning-based,deep learning-based,and hybrid-based methods,and aims to explore the ongoing difficulties in the field.We summarize and classify the methods used in each article,compare the strengths and weaknesses of traditional image processing-based,machine learning-based,deep learning-based,and hybrid-based methods,and review benchmark datasets for pill image recognition.Additionally,we compare the performance of proposed methods on popular benchmark datasets.This survey applies recent advancements,such as Transformer models and cutting-edge technologies like Augmented Reality(AR),to discuss potential research directions and conclude the review.By offering a holistic perspective,this paper aims to serve as a valuable resource for researchers and practitioners striving to advance the field of pill image recognition.
基金supported by the National Science Foundations of China(No.61905256)the National Key Research and Development Program of China(No.2019YFC0214702)the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2020439)。
文摘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.
基金supported by the National Natural Science Foundation of China(T2394531)the National Key R&D Program of China(2024YFF1206500)+1 种基金the Shanghai Municipal Science and Technology Major Project(2018SHZDZX01)ZJ Lab,and the Shanghai Center for Brain Science and Brain-Inspired Technology,China.
文摘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].
文摘Background:Testicular sperm aspiration(TESA)is a minimally invasive testicular sperm retrieval technique that has been utilized in the treatment of male factor infertility.We sought to evaluate sperm retrieval outcomes of primary and redo TESA in men with severe oligoasthenoteratozoospermia(OAT)and obstructive azoospermia(OA).Methods:This is a retrospective analysis of consecutive TESAs(primary and redo)for men with severe OAT and OA performed between January 2011 and August 2022 at a high-volume infertility center.We compared TESA outcomes in men with severe OAT to those with OA and compared outcomes of men who underwent primary and redo TESA on the same testicular unit.Results:439 TESAs(366 primary and 73 redo)in men with severe OAT(n=133)and OA(n=306)were included.Men with OA had significantly higher sperm retrieval rate(SRR)and motile SRR compared to men with severe OAT(99%vs.95%and 98%vs.83%,respectively,p<0.05).The requirement for multiple biopsies and the total number of aspirates were significantly lower in men with OA compared to those with severe OAT(15%vs.32%and 1.2±0.5 vs.1.4±0.7,respectively,p<0.05).In both groups,SRR,motile SRR,the requirement for multiple biopsies,and the total number of aspirates were not significantly different in primary compared to redo cases.Conclusion:Our data demonstrate that TESA retrieval rates are significantly higher in men with OA compared to those with severe OAT.The data also demonstrate that a redo TESA in these men is as effective as a primary TESA,suggesting that areas of active spermatogenesis are preserved 6 months after TESA.
基金The authors extend their appreciation to the Deanship of Research and Graduate Studies at King Khalid University,Kingdom of Saudi Arabia,for funding this work through the Small Research Group Project under Grant Number RGP.1/316/45.
文摘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.
基金funded by the National Key Research and Development Program of China(2022YFF0711603)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA28020503)+2 种基金the National Natural Science Foundation of China(Grant No.42371399,42301431)Basic Research Program of Jiangsu(Grant No.BK20240112)the Science and Technology Planning Project of NIGLAS(Grant No.2022NIGLAS-CJH04).
文摘Reliable surface height observations over inland water bodies are useful for understanding the hydrological cycle.Satellite radar altimetry particularly contributed with its long-term archive and minimal cloud interference.Specialized inland water altimetry,developed from oceanography and geodesy,is still being extensively investigated.By synthesizing pioneering studies on“retracking algorithms”,this review demonstrates,from a user perspective,why optimizing conventional retracking is still important and how it can extend reliable historical water level retrieval over more ungauged sites.Numerous unrevealed inland water bodies have small sizes or complex surroundings,posing challenges to maintaining accuracy.Applications have shown that a critical key lies in the retracking correction during range retrieval(uncertainty likely on the order of meters),compared with other corrections(on the order of centimeters or decimeters).From multiple uncertainty factors in range retrieval,signal entanglements from land contamination and off-nadir effects are core issues.We evaluate and compared key strategies from prototype retrackers to improved retrackers,especially the empirical ones optimized for inland waters.Sub-waveform extraction and adjustment for Delay-Doppler modes has advanced range retrieval to a new stage.Four innovative inland-water-compatible retrackers are introduced in detail,with a highlight on their distinct approaches to robustly improve performance.Considering the selection of different data and retrackers in varying scenarios,a synthesis analysis is conducted based on results reported in previous literature.In conclusion,the empirical retracking has been enhanced to offer stable decimeter-level accuracy in intricate landscapes(e.g.,small lakes and rivers with varied surroundings).In comparison,the physical retracking has been upgraded to provide greater precision for homogeneous surface in large lakes.For future inland water altimetry,we articulate how additionally retracked results can benefit hydrological applications,and what difficulties would arise when extending study scales.
文摘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.
基金supported by the National Natural Science Foundation of China(Nos.12072027,62103052,61603346 and 62103379)the Henan Key Laboratory of General Aviation Technology,China(No.ZHKF-230201)+3 种基金the Funding for the Open Research Project of the Rotor Aerodynamics Key Laboratory,China(No.RAL20200101)the Key Research and Development Program of Henan Province,China(Nos.241111222000 and 241111222900)the Key Science and Technology Program of Henan Province,China(No.232102220067)the Scholarship Funding from the China Scholarship Council(No.202206030079).
文摘In global navigation satellite system denial environment,cross-view geo-localization based on image retrieval presents an exceedingly critical visual localization solution for Unmanned Aerial Vehicle(UAV)systems.The essence of cross-view geo-localization resides in matching images containing the same geographical targets from disparate platforms,such as UAV-view and satellite-view images.However,images of the same geographical targets may suffer from occlusions and geometric distortions due to variations in the capturing platform,view,and timing.The existing methods predominantly extract features by segmenting feature maps,which overlook the holistic semantic distribution and structural information of objects,resulting in loss of image information.To address these challenges,dilated neighborhood attention Transformer is employed as the feature extraction backbone,and Multi-feature representations based on Multi-scale Hierarchical Contextual Aggregation(MMHCA)is proposed.In the proposed MMHCA method,the multiscale hierarchical contextual aggregation method is utilized to extract contextual information from local to global across various granularity levels,establishing feature associations of contextual information with global and local information in the image.Subsequently,the multi-feature representations method is utilized to obtain rich discriminative feature information,bolstering the robustness of model in scenarios characterized by positional shifts,varying distances,and scale ambiguities.Comprehensive experiments conducted on the extensively utilized University-1652 and SUES-200 benchmarks indicate that the MMHCA method surpasses the existing techniques.showing outstanding results in UAV localization and navigation.
基金supported by the Shenzhen Fundamental Research Program(No.JCYJ20210324121807021).
文摘To investigate the impact of preoperative serum follicle-stimulating hormone(FSH)levels on the probability of testicular sperm retrieval,we conducted a study of nonobstructive azoospermic(NOA)men with different testicular volumes(TVs)who underwent microdissection testicular sperm extraction(micro-TESE).A total of 177 NOA patients undergoing micro-TESE for the first time from April 2019 to November 2022 in Shenzhen Zhongshan Obstetrics and Gynecology Hospital(formerly Shenzhen Zhongshan Urology Hospital,Shenzhen,China)were retrospectively reviewed.The subjects were divided into four groups based on average TV quartiles.Serum hormone levels in each TV group were compared between positive and negative sperm retrieval subgroups.Overall sperm retrieval rate was 57.6%.FSH levels(median[interquartile range])were higher in the positive sperm retrieval subgroup compared with the negative outcome subgroup when average TV was<5 ml(first quartile[Q1:TV<3 ml]:43.32[17.92]IU l^(−1) vs 32.95[18.56]IU l−1,P=0.048;second quartile[Q2:3 ml≤TV<5 ml]:31.31[15.37]IU l^(−1) vs 25.59[18.40]IU l^(−1),P=0.042).Elevated serum FSH levels were associated with successful micro-TESE sperm retrieval in NOA men whose average TVs were<5 ml(adjusted odds ratio[OR]:1.06 per unit increase;95%confidence interval[CI]:1.01–1.11;P=0.011).In men with TVs≥5 ml,larger TVs were associated with lower odds of sperm retrieval(adjusted OR:0.84 per 1 ml increase;95%CI:0.71–0.98;P=0.029).In conclusion,elevated serum FSH levels were associated with positive sperm retrieval in micro-TESE in NOA men with TVs<5 ml.In men with TV≥5 ml,increases in average TVs were associated with lower odds of sperm retrieval.
基金supported by the National Natural Science Foundation of China[Grant Nos.42205086 and 42122038]。
文摘Mixed-phase clouds(MPCs)involve complex microphysical and dynamical processes of cloud formation and dissipation,which are crucial for numerical weather prediction and cloud-climate feedback.However,satellite remote sensing of MPC properties is still challenging,and there is seldom MPC result inferred from passive spectral observations.This study examines the spectral characteristics of MPCs in the shortwave-infrared(SWIR)channels over the wavelength of 0.4–2.5μm,and evaluates the potential of current operational satellite spectroradiometer channels for MPC retrievals.With optical properties of MPCs based on the assumption of uniform mixing of both ice and liquid water particles,the effects of MPC ice optical thickness fraction(IOTF)and effective radius on associated optical properties are analyzed.As expected,results indicate that the MPC optical properties show features for ice and liquid water clouds,and their spectral variations show noticeable differences from those for homogeneous cases.A radiative transfer method is employed to examine the sensitivity of SWIR channels to given MPC cloud water path(CWP)and IOTF.MPCs have unique signal characteristics in the SWIR spectrum.The 0.87-μm channel is most sensitive to CWP.Meanwhile,the 1.61-and 2.13-μm channels are more sensitive to water-dominated MPCs(IOTF approaching 0),and the 2.25-μm channel is sensitive to both water-dominated and ice-dominated MPCs(IOTF approaching 1).Such spectral differences are potentially possible to be used to infer MPC properties based on radiometer observations,which will be investigated in future studies.
基金supported by the National Natural Science Foundation of China(Grant Nos.42030708,42375138,42030608,42105128,42075079)the Opening Foundation of Key Laboratory of Atmospheric Sounding,China Meteorological Administration(CMA),and the CMA Research Center on Meteorological Observation Engineering Technology(Grant No.U2021Z03),and the Opening Foundation of the Key Laboratory of Atmospheric Chemistry,CMA(Grant No.2022B02)。
文摘Aerosol optical depth(AOD)and fine particulate matter with a diameter of less than or equal to 2.5μm(PM_(2.5))play crucial roles in air quality,human health,and climate change.However,the complex correlation of AOD–PM_(2.5)and the limitations of existing algorithms pose a significant challenge in realizing the accurate joint retrieval of these two parameters at the same location.On this point,a multi-task learning(MTL)model,which enables the joint retrieval of PM_(2.5)concentration and AOD,is proposed and applied on the top-of-the-atmosphere reflectance data gathered by the Fengyun-4A Advanced Geosynchronous Radiation Imager(FY-4A AGRI),and compared to that of two single-task learning models—namely,Random Forest(RF)and Deep Neural Network(DNN).Specifically,MTL achieves a coefficient of determination(R^(2))of 0.88 and a root-mean-square error(RMSE)of 0.10 in AOD retrieval.In comparison to RF,the R^(2)increases by 0.04,the RMSE decreases by 0.02,and the percentage of retrieval results falling within the expected error range(Within-EE)rises by 5.55%.The R^(2)and RMSE of PM_(2.5)retrieval by MTL are 0.84 and 13.76μg m~(-3)respectively.Compared with RF,the R^(2)increases by 0.06,the RMSE decreases by 4.55μg m~(-3),and the Within-EE increases by 7.28%.Additionally,compared to DNN,MTL shows an increase of 0.01 in R^(2)and a decrease of 0.02 in RMSE in AOD retrieval,with a corresponding increase of 2.89%in Within-EE.For PM_(2.5)retrieval,MTL exhibits an increase of 0.05 in R^(2),a decrease of 1.76μg m~(-3)in RMSE,and an increase of 6.83%in Within-EE.The evaluation suggests that MTL is able to provide simultaneously improved AOD and PM_(2.5)retrievals,demonstrating a significant advantage in efficiently capturing the spatial distribution of PM_(2.5)concentration and AOD.
文摘Infertility,defined as the inability to conceive after 1 year of regular unprotected intercourse,impacts 10%–20%of couples globally.Both male and female factors contribute equally to this condition.Azoospermia,particularly nonobstructive azoospermia(NOA),which affects 10%–15%of infertile men,represents a significant challenge in male infertility.The advent of assisted reproductive technology(ART),specifically microdissection testicular sperm extraction(micro-TESE)followed by intracytoplasmic sperm injection(ICSI),offers a possibility for men with NOA to father biological children.Recent studies have focused on the predictors of sperm retrieval in NOA patients,such as age,testicular volume,and follicle-stimulating hormone(FSH)level.This review aims to explore the limited data on the anatomical characteristics of NOA patients and provide surgical considerations for micro-TESE,thereby enhancing understanding and improving outcomes for this challenging condition.
基金Supported by the National Natural Science Foundation of China(No.61971162,61771186)the Natural Science Foundation of Heilongjiang Province(No.PL2024F025)+2 种基金the Open Research Fund of National Mobile Communications Research Laboratory Southeast University(No.2023D07)the Outstanding Youth Program of Natural Science Foundation of Heilongjiang Province(No.YQ2020F012)the Funda-mental Scientific Research Funds of Heilongjiang Province(No.2022-KYYWF-1050).
文摘Indoor visual localization relies heavily on image retrieval to ascertain location information.However,the widespread presence and high consistency of floor patterns across different images of-ten lead to the extraction of numerous repetitive features,thereby reducing the accuracy of image retrieval.This article proposes an indoor visual localization method based on semantic segmentation and adaptive weight fusion to address the issue of ground texture interference with retrieval results.During the positioning process,an indoor semantic segmentation model is established.Semantic segmentation technology is applied to accurately delineate the ground portion of the images.Fea-ture extraction is performed on both the original database and the ground-segmented database.The vector of locally aggregated descriptors(VLAD)algorithm is then used to convert image features into a fixed-length feature representation,which improves the efficiency of image retrieval.Simul-taneously,a method for adaptive weight optimization in similarity calculation is proposed,using a-daptive weights to compute similarity for different regional features,thereby improving the accuracy of image retrieval.The experimental results indicate that this method significantly reduces ground interference and effectively utilizes ground information,thereby improving the accuracy of image retrieval.
文摘1 The need to refine journal subject classification systems Journal subject classification systems are fundamental to journal evaluation,research assessments and information retrieval.Previous studies(e.g.,Wang&Waltman,2016)have identified accuracy issues in major classification systems such as the Subject Categories in the Web of Science and ASJC in Scopus.
基金funded by the Scientific Funding for China Academy of Railway Sciences Corporation Limited,China(No.2023YJ125).
文摘Speech-face association aims to achieve identity matching between facial images and voice segments by aligning cross-modal features.Existing research primarily focuses on learning shared-space representations and computing one-to-one similarities between cross-modal sample pairs to establish their correlation.However,these approaches do not fully account for intra-class variations between the modalities or the many-to-many relationships among cross-modal samples,which are crucial for robust association modeling.To address these challenges,we propose a novel framework that leverages global information to align voice and face embeddings while effectively correlating identity information embedded in both modalities.First,we jointly pre-train face recognition and speaker recognition networks to encode discriminative features from facial images and voice segments.This shared pre-training step ensures the extraction of complementary identity information across modalities.Subsequently,we introduce a cross-modal simplex center loss,which aligns samples with identity centers located at the vertices of a regular simplex inscribed on a hypersphere.This design enforces an equidistant and balanced distribution of identity embeddings,reducing intra-class variations.Furthermore,we employ an improved triplet center loss that emphasizes hard sample mining and optimizes inter-class separability,enhancing the model’s ability to generalize across challenging scenarios.Extensive experiments validate the effectiveness of our framework,demonstrating superior performance across various speech-face association tasks,including matching,verification,and retrieval.Notably,in the challenging gender-constrained matching task,our method achieves a remarkable accuracy of 79.22%,significantly outperforming existing approaches.These results highlight the potential of the proposed framework to advance the state of the art in cross-modal identity association.
基金supported by the Innovation Program for Quantum Science and technology(2021ZD0301300)supported by the Fundamental Research Funds for the Central Universities(Nos.3282024046,3282024052,3282024058,3282023017).
文摘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.
