AIM:To assess the feasibility and safety of the use of soehendra stent retriever as a new technique for biliary access in endoscopic ultrasound-guided biliary drainage.METHODS:The medical records and endoscopic report...AIM:To assess the feasibility and safety of the use of soehendra stent retriever as a new technique for biliary access in endoscopic ultrasound-guided biliary drainage.METHODS:The medical records and endoscopic reports of the patients who underwent endoscopic ultrasound-guided biliary drainage(EUS-BD) owing to failed endoscopic retrograde cholangiopancreatography in our institute between June 2011 and January 2014 were collected and reviewed.All the procedures were performed in the endoscopic suite under intravenous sedation with propofol and full anaesthetic monitoring.Then we used the Soehendra stent retriever as new equipment for neo-tract creation and dilation when performing EUS-BD procedures.The patients were observed in the recovery room for 1-2 h and transferred to the regular ward,patients' clinical data were reviewed and analysed,clinical outcomes were defined by using several different criteria.Data were analysed by using SPSS 13 and presented as percentages,means,and medians.RESULTS:A total of 12 patients were enrolled.The most common indications for EUS-BD in this series were failed common bile duct cannulation,duodenal obstruction,failed selective intrahepatic duct cannulation,and surgical altered anatomy for 50%,25%,16.7%,and 8.3%,respectively.Seven patients underwent EUS-guided hepaticogastrostomy(58.3%),and 5 underwent EUS-guided choledochoduodenostomy(41.7%).The technical success rate was 100%,while the clinical success rate was 91.7%.Major and minor complications occurred in 16.6% and 33.3% of patients,respectively,but there were no procedurerelated death.CONCLUSION:Soehendra stent retriever could be used as an alternative instrument for biliary access in endoscopic ultrasound guided biliary drainage.展开更多
Bilioenteric or pancreatoenteric anastomotic stric-tures often occur after surgery for a pancreaticobiliary disorder. Therapeutic endoscopic retrograde cholan-giopancreatography using balloon enteroscopy has been show...Bilioenteric or pancreatoenteric anastomotic stric-tures often occur after surgery for a pancreaticobiliary disorder. Therapeutic endoscopic retrograde cholan-giopancreatography using balloon enteroscopy has been shown to be feasible and effective in patients with such strictures. However, when a benign anas-tomotic stricture is severe, a dilation catheter cannot pass through the stricture despite successful insertion of the guidewire. We report on the usefulness of the Soehendra Stent Retriever over a guidewire for dilating a severe bilioenteric or pancreatoenteric anastomotic stricture under short double-balloon enteroscopy, in two patients with surgically altered anatomies.展开更多
BACKGROUND The prognostic value of quantitative assessments of the number of retrieved lymph nodes(RLNs)in gastric cancer(GC)patients needs further study.AIM To discuss how to obtain a more accurate count of metastati...BACKGROUND The prognostic value of quantitative assessments of the number of retrieved lymph nodes(RLNs)in gastric cancer(GC)patients needs further study.AIM To discuss how to obtain a more accurate count of metastatic lymph nodes(MLNs)based on RLNs in different pT stages and then to evaluate patient prognosis.METHODS This study retrospectively analyzed patients who underwent GC radical surgery and D2/D2+LN dissection at the Cancer Hospital of Harbin Medical University from January 2011 to May 2017.Locally weighted smoothing was used to analyze the relationship between RLNs and the number of MLNs.Restricted cubic splines were used to analyze the relationship between RLNs and hazard ratios(HRs),and X-tile was used to determine the optimal cutoff value for RLNs.Patient survival was analyzed with the Kaplan-Meier method and log-rank test.Finally,HRs and 95%confidence intervals were calculated using Cox proportional hazards models to analyze independent risk factors associated with patient outcomes.RESULTS A total of 4968 patients were included in the training cohort,and 11154 patients were included in the validation cohort.The smooth curve showed that the number of MLNs increased with an increasing number of RLNs,and a nonlinear relationship between RLNs and HRs was observed.X-tile analysis showed that the optimal number of RLNs for pT1-pT4 stage GC patients was 26,31,39,and 45,respectively.A greater number of RLNs can reduce the risk of death in patients with pT1,pT2,and pT4 stage cancers but may not reduce the risk of death in patients with pT3 stage cancer.Multivariate analysis showed that RLNs were an independent risk factor associated with the prognosis of patients with pT1-pT4 stage cancer(P=0.044,P=0.037,P=0.003,P<0.001).CONCLUSION A greater number of RLNs may not benefit the survival of patients with pT3 stage disease but can benefit the survival of patients with pT1,pT2,and pT4 stage disease.For the pT1,pT2,and pT4 stages,it is recommended to retrieve 26,31 and 45 LNs,respectively.展开更多
Objective: To compare the numbers of positive and total lymph nodes and prognosis in gastric cancer patients whose perigastric lymph node retrieval was performed by surgeons and pathologists.Methods: We conducted a re...Objective: To compare the numbers of positive and total lymph nodes and prognosis in gastric cancer patients whose perigastric lymph node retrieval was performed by surgeons and pathologists.Methods: We conducted a retrospective analysis of clinical and follow-up data from 1,056 patients who underwent gastric cancer D2 radical lymph node resection between January 2008 and December 2010 in the Gastrointestinal Surgery Department of Yantai Yuhuangding Hospital.The follow-up ended in December 2015.Patients were divided into two groups according to the specialty of physicians who performed the postoperative perigastric lymph node retrieval: the surgeon group(475 cases) and the pathologist group(581 cases).The numbers of positive and total perigastric lymph nodes and the 3- and 5-year survival were compared between gastric cancer patients in the two groups overall and stratified by TNM stage(AJCC 7th Edition).Results: Overall, the numbers of positive and total lymph nodes were significantly higher in the surgeon group than in the pathologist group(6.53±4.07 vs.4.09±3.70, P=0.021; 29.64±11.50 vs.20.71±8.56, P<0.001).Further analysis showed that the total number of lymph nodes in stage Ⅰ patients(19.40±9.62 vs.15.45±8.59, P=0.011) and the numbers of positive and total lymph nodes in stage Ⅱ(1.38±1.08 vs.0.87±1.55, P=0.031; 25.35±10.80 vs.16.75±8.56, P<0.001) and stage Ⅲ patients(8.11±6.91 vs.6.66±5.12, P=0.026; 32.34±12.55 vs.25.45±8.31, P<0.001)were significantly higher in the surgeon group than in the pathologist group.The survival analysis showed that the3- and 5-year survival of stage Ⅱ and Ⅲ patients was significantly higher in the surgeon group than in the pathologist group(82.0% vs.73.1%, 69.5% vs.61.2%, P=0.038; 49.2% vs.38.9%, 36.3% vs.28.0%; P=0.045).Conclusions: Compared with retrieval performed by pathologists, postoperative perigastric lymph node retrieval performed by surgeons was associated with significant increase in the total lymph node number of stage Ⅰ patients, the numbers of positive and total lymph nodes of stage Ⅱ and Ⅲ patients, and the survival of stage Ⅱ and stage Ⅲ gastric cancer patients.展开更多
Accidentally swallowed foreign objects are not uncommon but difficult to manage without complications. We describe the case of a 68 year old man who accidentally a swallowed sharp-pointed dental reamer that had reache...Accidentally swallowed foreign objects are not uncommon but difficult to manage without complications. We describe the case of a 68 year old man who accidentally a swallowed sharp-pointed dental reamer that had reached deep in his jejunum. Double balloon enteroscopic retrieval was performed with polypectomy snare but the reamer was entangled in the wire loop of the snare and penetrated the jejunal wall. After releasing the reamer by pushing and pulling the snare for approximately 30 min, the reamer was retrieved with biopsy forceps. This is the first report of double balloon enteroscopic removal of a dental reamer. Furthermore, this is a novel case with regard to decision making in situations when sharp objects are swallowed.展开更多
The objective of this research was to acquire a raindrop size distribution(DSDs)retrieved from C-band polarimetric radar observations scheme for the first time in south China.An observation period of the precipitation...The objective of this research was to acquire a raindrop size distribution(DSDs)retrieved from C-band polarimetric radar observations scheme for the first time in south China.An observation period of the precipitation process was selected,and the shape-slope(μ-Λ)relationship of this region was statistically analyzed using the raindrop sample observations from the two-dimensional video disdrometer(2DVD)at Xinfeng Station,Guangdong Province.Simulated data of the C-band polarimetric radar reflectivity ZHHand differential reflectivity ZDRwere obtained through scattering simulation.The simulation data were combined with DSD fitting to determine the ZDR-Λand log10(ZHH/N0)-Λrelationships.Using Xinfeng C-band polarimetric radar observations ZDRand ZHH,the raindrop Gamma size distribution parametersμ,Λ,and N0were retrieved.A scheme for using C-band polarimetric radar to retrieve the DSDs was developed.This research revealed that during precipitation process,the DSDs obtained using the C-band polarimetric radar retrieval scheme are similar to the 2DVD observations,the precipitation characteristics of rainfall intensity(R),mass-weighted mean diameter(Dm)and intercept parameter(Nw)with time obtained by radar retrieval are basically consistent with the observational results of the 2DVD.This scheme establishes the relationship between the observations of the C-band polarimetric radar and the physical quantities of the numerical model.This method not only can test the prediction of the model data assimilation system on the convective scale and determine error sources,but also can improve the microphysical precipitation processes analysis and radar quantitative precipitation estimation.The present research will facilitate radar data assimilation in the future.展开更多
One-dimensional retrieval was performed on Typhoon Haiyan utilizing the advanced technology microwave sounder onboard the satellite Suomi NPP to retrieve the temperature and water vapor profiles of the typhoon.Compari...One-dimensional retrieval was performed on Typhoon Haiyan utilizing the advanced technology microwave sounder onboard the satellite Suomi NPP to retrieve the temperature and water vapor profiles of the typhoon.Comparisons of the retrieved profiles and ECMWF reanalysis were made to assess the results. The main conclusions are as follows.(1) The results have high spatial resolution and therefore can precisely represent the temperature and humidity distribution of the typhoon.(2) The retrieved temperature is low in the areas of low temperature and high in the areas of high temperature; similar patterns are observed for humidity. This means that systematic revision may be needed during routine application.(3) The results of the retrieved temperature and humidity profiles are generally accurate, which is quite important for typhoon monitoring.展开更多
Wind shear reflects that the wind field is not uniform, which is one of the primary factors which make the retrieval of the wind field difficult. Based on volume velocity process(VVP) wind field retrieval technique, t...Wind shear reflects that the wind field is not uniform, which is one of the primary factors which make the retrieval of the wind field difficult. Based on volume velocity process(VVP) wind field retrieval technique, the intensity of wind shear is identified in this paper. After analyzing the traditional techniques that rely on the difference of radial velocity to identify wind shear, a fixed difference among radial velocities that may cause false identification in a uniform wind field was found. Because of the non-uniformity in wind shear areas, the difference of retrieved results between surrounding analysis volumes can be used as a measurement to show how strong the wind shear is. According to the analysis of a severe convective weather process that occurred in Guangzhou, it can be found that the areas of wind shear appeared with the strength significantly larger than in other regions and the magnitude generally larger than4.5 m/(s·km). Besides, by comparing the variation of wind shear strength during the convection, it can be found that new cells will be more likely to generate when the strength is above 3.0 m/(s·km). Therefore, the analysis of strong wind shear's movement and development is helpful to forecasting severe convections.展开更多
Web search provides a promising way for people to obtain information and has been extensively studied.With the surge of deep learning and large-scale pre-training techniques,various neural information retrieval models...Web search provides a promising way for people to obtain information and has been extensively studied.With the surge of deep learning and large-scale pre-training techniques,various neural information retrieval models are proposed,and they have demonstrated the power for improving search(especially,the ranking)quality.All these existing search methods follow a common paradigm,i.e.,index-retrieve-rerank,where they first build an index of all documents based on document terms(i.e.,sparse inverted index)or representation vectors(i.e.,dense vector index),then retrieve and rerank retrieved documents based on the similarity between the query and documents via ranking models.In this paper,we explore a new paradigm of information retrieval without an explicit index but only with a pre-trained model.Instead,all of the knowledge of the documents is encoded into model parameters,which can be regarded as a differentiable indexer and optimized in an end-to-end manner.Specifically,we propose a pre-trained model-based information retrieval(IR)system called DynamicRetriever,which directly returns document identifiers for a given query.Under such a framework,we implement two variants to explore how to train the model from scratch and how to combine the advantages of dense retrieval models.Compared with existing search methods,the model-based IR system parameterizes the traditional static index with a pre-training model,which converts the document semantic mapping into a dynamic and updatable process.Extensive experiments conducted on the public search benchmark Microsoft machine reading comprehension(MS MARCO)verify the effectiveness and potential of our proposed new paradigm for information retrieval.展开更多
Apricot has a long history of cultivation and has many varieties and types. The traditional variety identification methods are timeconsuming and labor-consuming, posing grand challenges to apricot resource management....Apricot has a long history of cultivation and has many varieties and types. The traditional variety identification methods are timeconsuming and labor-consuming, posing grand challenges to apricot resource management. Tool development in this regard will help researchers quickly identify variety information. This study photographed apricot fruits outdoors and indoors and constructed a dataset that can precisely classify the fruits using a U-net model (F-score:99%), which helps to obtain the fruit's size, shape, and color features. Meanwhile, a variety search engine was constructed, which can search and identify variety from the database according to the above features. Besides, a mobile and web application (ApricotView) was developed, and the construction mode can be also applied to other varieties of fruit trees.Additionally, we have collected four difficult-to-identify seed datasets and used the VGG16 model for training, with an accuracy of 97%, which provided an important basis for ApricotView. To address the difficulties in data collection bottlenecking apricot phenomics research, we developed the first apricot database platform of its kind (ApricotDIAP, http://apricotdiap.com/) to accumulate, manage, and publicize scientific data of apricot.展开更多
The developed system for eye and face detection using Convolutional Neural Networks(CNN)models,followed by eye classification and voice-based assistance,has shown promising potential in enhancing accessibility for ind...The developed system for eye and face detection using Convolutional Neural Networks(CNN)models,followed by eye classification and voice-based assistance,has shown promising potential in enhancing accessibility for individuals with visual impairments.The modular approach implemented in this research allows for a seamless flow of information and assistance between the different components of the system.This research significantly contributes to the field of accessibility technology by integrating computer vision,natural language processing,and voice technologies.By leveraging these advancements,the developed system offers a practical and efficient solution for assisting blind individuals.The modular design ensures flexibility,scalability,and ease of integration with existing assistive technologies.However,it is important to acknowledge that further research and improvements are necessary to enhance the system’s accuracy and usability.Fine-tuning the CNN models and expanding the training dataset can improve eye and face detection as well as eye classification capabilities.Additionally,incorporating real-time responses through sophisticated natural language understanding techniques and expanding the knowledge base of ChatGPT can enhance the system’s ability to provide comprehensive and accurate responses.Overall,this research paves the way for the development of more advanced and robust systems for assisting visually impaired individuals.By leveraging cutting-edge technologies and integrating them into amodular framework,this research contributes to creating a more inclusive and accessible society for individuals with visual impairments.Future work can focus on refining the system,addressing its limitations,and conducting user studies to evaluate its effectiveness and impact in real-world scenarios.展开更多
Recently,deep learning has yielded transformative success across optics and photonics,especially in optical metrology.Deep neural networks (DNNs) with a fully convolutional architecture (e.g.,U-Net and its derivatives...Recently,deep learning has yielded transformative success across optics and photonics,especially in optical metrology.Deep neural networks (DNNs) with a fully convolutional architecture (e.g.,U-Net and its derivatives) have been widely implemented in an end-to-end manner to accomplish various optical metrology tasks,such as fringe denoising,phase unwrapping,and fringe analysis.However,the task of training a DNN to accurately identify an image-to-image transform from massive input and output data pairs seems at best naive,as the physical laws governing the image formation or other domain expertise pertaining to the measurement have not yet been fully exploited in current deep learning practice.To this end,we introduce a physics-informed deep learning method for fringe pattern analysis (PI-FPA) to overcome this limit by integrating a lightweight DNN with a learning-enhanced Fourier transform profilometry (Le FTP) module.By parameterizing conventional phase retrieval methods,the Le FTP module embeds the prior knowledge in the network structure and the loss function to directly provide reliable phase results for new types of samples,while circumventing the requirement of collecting a large amount of high-quality data in supervised learning methods.Guided by the initial phase from Le FTP,the phase recovery ability of the lightweight DNN is enhanced to further improve the phase accuracy at a low computational cost compared with existing end-to-end networks.Experimental results demonstrate that PI-FPA enables more accurate and computationally efficient single-shot phase retrieval,exhibiting its excellent generalization to various unseen objects during training.The proposed PI-FPA presents that challenging issues in optical metrology can be potentially overcome through the synergy of physics-priors-based traditional tools and data-driven learning approaches,opening new avenues to achieve fast and accurate single-shot 3D imaging.展开更多
Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human...Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human settlements,it is significant for exploring the evolution characteristics of urban thermal environment and analyzing its driving forces.Taking the Landsat series images as the basic data sources,the winter land surface temperature(LST)of the rapid urbanization area of Fuzhou City in China was quantitatively retrieved from 2001 to 2021.Combing comprehensively the standard deviation ellipse model,profile analysis and GeoDetector model,the spatio-temporal evolution characteristics and influencing factors of the winter urban thermal environment were systematically analyzed.The results showed that the winter LST presented an increasing trend in the study area during 2001–2021,and the winter LST of the central urban regions was significantly higher than the suburbs.There was a strong UHI effect from 2001 to 2021with an expansion trend from the central urban regions to the suburbs and coastal areas in space scale.The LST of green lands and wetlands are significantly lower than croplands,artificial surface and unvegetated lands.Vegetation and water bodies had a significant mitigation effect on UHI,especially in the micro-scale.The winter UHI had been jointly driven by the underlying surface and socio-economic factors in a nonlinear or two-factor interactive enhancement mode,and socio-economic factors had played a leading role.This research could provide data support and decision-making references for rationally planning urban layout and promoting sustainable urban development.展开更多
Background A medical content-based image retrieval(CBIR)system is designed to retrieve images from large imaging repositories that are visually similar to a user′s query image.CBIR is widely used in evidence-based di...Background A medical content-based image retrieval(CBIR)system is designed to retrieve images from large imaging repositories that are visually similar to a user′s query image.CBIR is widely used in evidence-based diagnosis,teaching,and research.Although the retrieval accuracy has largely improved,there has been limited development toward visualizing important image features that indicate the similarity of retrieved images.Despite the prevalence of 3D volumetric data in medical imaging such as computed tomography(CT),current CBIR systems still rely on 2D cross-sectional views for the visualization of retrieved images.Such 2D visualization requires users to browse through the image stacks to confirm the similarity of the retrieved images and often involves mental reconstruction of 3D information,including the size,shape,and spatial relations of multiple structures.This process is time-consuming and reliant on users'experience.Methods In this study,we proposed an importance-aware 3D volume visualization method.The rendering parameters were automatically optimized to maximize the visibility of important structures that were detected and prioritized in the retrieval process.We then integrated the proposed visualization into a CBIR system,thereby complementing the 2D cross-sectional views for relevance feedback and further analyses.Results Our preliminary results demonstrate that 3D visualization can provide additional information using multimodal positron emission tomography and computed tomography(PETCT)images of a non-small cell lung cancer dataset.展开更多
Objective:This paper aims to evaluate the implementation effect of the diversified course assessment method reform.Methods:A diversified assessment method was implemented for 196 undergraduate nursing students.Student...Objective:This paper aims to evaluate the implementation effect of the diversified course assessment method reform.Methods:A diversified assessment method was implemented for 196 undergraduate nursing students.Students’mastery of key knowledge in“Nursing Research”was assessed through group reports on topic selection and literature retrieval,as well as the proposition level of the final examination.Results:81.6%of the students agreed with the course assessment method,and 97.9%believed studying“Nursing Research”would be helpful for future scientific research applications.Conclusion:Diversified assessment methods can help improve undergraduate nursing students’scientific research skills and comprehensive quality.展开更多
The task of indoor visual localization, utilizing camera visual information for user pose calculation, was a core component of Augmented Reality (AR) and Simultaneous Localization and Mapping (SLAM). Existing indoor l...The task of indoor visual localization, utilizing camera visual information for user pose calculation, was a core component of Augmented Reality (AR) and Simultaneous Localization and Mapping (SLAM). Existing indoor localization technologies generally used scene-specific 3D representations or were trained on specific datasets, making it challenging to balance accuracy and cost when applied to new scenes. Addressing this issue, this paper proposed a universal indoor visual localization method based on efficient image retrieval. Initially, a Multi-Layer Perceptron (MLP) was employed to aggregate features from intermediate layers of a convolutional neural network, obtaining a global representation of the image. This approach ensured accurate and rapid retrieval of reference images. Subsequently, a new mechanism using Random Sample Consensus (RANSAC) was designed to resolve relative pose ambiguity caused by the essential matrix decomposition based on the five-point method. Finally, the absolute pose of the queried user image was computed, thereby achieving indoor user pose estimation. The proposed indoor localization method was characterized by its simplicity, flexibility, and excellent cross-scene generalization. Experimental results demonstrated a positioning error of 0.09 m and 2.14° on the 7Scenes dataset, and 0.15 m and 6.37° on the 12Scenes dataset. These results convincingly illustrated the outstanding performance of the proposed indoor localization method.展开更多
Lunar regolith parameters, such as physical temperature, thickness and dielectric constant, are important in studying regolith features, distribution of lunar resources and evolution of the Moon. There had been no mea...Lunar regolith parameters, such as physical temperature, thickness and dielectric constant, are important in studying regolith features, distribution of lunar resources and evolution of the Moon. There had been no measurement obtained by lunar-orbit-borne microwave radiometer applied to evaluate the properties of lunar regolith before CE-1 Lunar Microwave Sounder (CELMS) being launched. CEMLS is the first passive microwave radiometer in the world to sound the surface of the Moon. The brightness temperatures (TB) sensed by CELMS include complicated information on the above geophysical parameters. In this paper, algorithms of retrieving dielectric constant, regolith thickness, and 3He content from CELMS brightness temperatures are developed, and the results are compared with those from literature. The results show that the regolith thicknesses are mostly in the range of 4.0-6.0 m, and 43% of them are bigger than 5.0 m. The content of 3He evaluated by retrieved regolith thickness is about 1.03 million tons.展开更多
In order to improve understanding of deep convective clouds over the Tibetan Plateau, characteristics of vertical structure of a deep strong convective cloud over Naqu station and a deep weak convective cloud approxim...In order to improve understanding of deep convective clouds over the Tibetan Plateau, characteristics of vertical structure of a deep strong convective cloud over Naqu station and a deep weak convective cloud approximately 100 km to the west of Naqu station, which occurred over 1300-1600 Beijing Time (BT) 9 July 2014 during the Third Tibetan Plateau Atmospheric Science Experiment (TIPEX-Ⅲ), are analyzed, based on multi-source satellite data from TRMM, CloudSat, and Aqua, and radar data from ground-based vertically pointing radars (C-band frequency-modulated continuous-wave radar and KA-band millimeter wave cloud radar). The results are as follows.(1) The horizontal scales of both the deep strong and deep weak convective clouds were small (10-20 km), and their tops were high[15-16 km above sea level (ASL)]. Across the level of 0℃ isotherm in the deep strong convective cloud, the reflectivity increased rapidly, suggesting that the melting process of solid precipitation particles through the 0℃ level played an important role. A bright band located at 5.5 km ASL (i.e., 1 km above ground level) appeared during the period of convection weakening.(2) The reflectivity values from TRMM precipitation radar below 11 km were found to be overestimated compared to those derived from the C-band frequency-modulated continuous-wave radar.(3) Deep convective clouds were mainly ice clouds, and there were rich small ice particles above 10 km, while few large ice particles were found below 10 km. The microphysical processes of deep strong and deep weak convective clouds mainly included mixed-phase process and glaciated process, and the mixed-phase process can be divided into two types:one was the rimming process below the level of -25℃(deep strong convective cloud) or -29℃(deep weak convective cloud) and the other was aggregation and deposition process above that level. The latter process was accompanied with fast increase in ice particle effective radius. The above evidence from space-based and ground-based observational data further clarify the characteristics of vertical structure of deep convective clouds over the Tibetan Plateau, and provide a basis for the evaluation of simulation results of deep convective clouds by cloud models.展开更多
In this paper, we show that to retrieve specified objects in massive remote sensing data set is very important in both practice and theory. An algorithm-based content retrieval in the massive data set is studied. To a...In this paper, we show that to retrieve specified objects in massive remote sensing data set is very important in both practice and theory. An algorithm-based content retrieval in the massive data set is studied. To avoid the loss of information, the algorithm based on the Support Vector Machine classification is proposed. Also, the experiment on the real data set is made.展开更多
文摘AIM:To assess the feasibility and safety of the use of soehendra stent retriever as a new technique for biliary access in endoscopic ultrasound-guided biliary drainage.METHODS:The medical records and endoscopic reports of the patients who underwent endoscopic ultrasound-guided biliary drainage(EUS-BD) owing to failed endoscopic retrograde cholangiopancreatography in our institute between June 2011 and January 2014 were collected and reviewed.All the procedures were performed in the endoscopic suite under intravenous sedation with propofol and full anaesthetic monitoring.Then we used the Soehendra stent retriever as new equipment for neo-tract creation and dilation when performing EUS-BD procedures.The patients were observed in the recovery room for 1-2 h and transferred to the regular ward,patients' clinical data were reviewed and analysed,clinical outcomes were defined by using several different criteria.Data were analysed by using SPSS 13 and presented as percentages,means,and medians.RESULTS:A total of 12 patients were enrolled.The most common indications for EUS-BD in this series were failed common bile duct cannulation,duodenal obstruction,failed selective intrahepatic duct cannulation,and surgical altered anatomy for 50%,25%,16.7%,and 8.3%,respectively.Seven patients underwent EUS-guided hepaticogastrostomy(58.3%),and 5 underwent EUS-guided choledochoduodenostomy(41.7%).The technical success rate was 100%,while the clinical success rate was 91.7%.Major and minor complications occurred in 16.6% and 33.3% of patients,respectively,but there were no procedurerelated death.CONCLUSION:Soehendra stent retriever could be used as an alternative instrument for biliary access in endoscopic ultrasound guided biliary drainage.
文摘Bilioenteric or pancreatoenteric anastomotic stric-tures often occur after surgery for a pancreaticobiliary disorder. Therapeutic endoscopic retrograde cholan-giopancreatography using balloon enteroscopy has been shown to be feasible and effective in patients with such strictures. However, when a benign anas-tomotic stricture is severe, a dilation catheter cannot pass through the stricture despite successful insertion of the guidewire. We report on the usefulness of the Soehendra Stent Retriever over a guidewire for dilating a severe bilioenteric or pancreatoenteric anastomotic stricture under short double-balloon enteroscopy, in two patients with surgically altered anatomies.
基金Supported by the Nn 10 Program of Harbin Medical University Cancer Hospital,No.Nn 10 PY 2017-03.
文摘BACKGROUND The prognostic value of quantitative assessments of the number of retrieved lymph nodes(RLNs)in gastric cancer(GC)patients needs further study.AIM To discuss how to obtain a more accurate count of metastatic lymph nodes(MLNs)based on RLNs in different pT stages and then to evaluate patient prognosis.METHODS This study retrospectively analyzed patients who underwent GC radical surgery and D2/D2+LN dissection at the Cancer Hospital of Harbin Medical University from January 2011 to May 2017.Locally weighted smoothing was used to analyze the relationship between RLNs and the number of MLNs.Restricted cubic splines were used to analyze the relationship between RLNs and hazard ratios(HRs),and X-tile was used to determine the optimal cutoff value for RLNs.Patient survival was analyzed with the Kaplan-Meier method and log-rank test.Finally,HRs and 95%confidence intervals were calculated using Cox proportional hazards models to analyze independent risk factors associated with patient outcomes.RESULTS A total of 4968 patients were included in the training cohort,and 11154 patients were included in the validation cohort.The smooth curve showed that the number of MLNs increased with an increasing number of RLNs,and a nonlinear relationship between RLNs and HRs was observed.X-tile analysis showed that the optimal number of RLNs for pT1-pT4 stage GC patients was 26,31,39,and 45,respectively.A greater number of RLNs can reduce the risk of death in patients with pT1,pT2,and pT4 stage cancers but may not reduce the risk of death in patients with pT3 stage cancer.Multivariate analysis showed that RLNs were an independent risk factor associated with the prognosis of patients with pT1-pT4 stage cancer(P=0.044,P=0.037,P=0.003,P<0.001).CONCLUSION A greater number of RLNs may not benefit the survival of patients with pT3 stage disease but can benefit the survival of patients with pT1,pT2,and pT4 stage disease.For the pT1,pT2,and pT4 stages,it is recommended to retrieve 26,31 and 45 LNs,respectively.
文摘Objective: To compare the numbers of positive and total lymph nodes and prognosis in gastric cancer patients whose perigastric lymph node retrieval was performed by surgeons and pathologists.Methods: We conducted a retrospective analysis of clinical and follow-up data from 1,056 patients who underwent gastric cancer D2 radical lymph node resection between January 2008 and December 2010 in the Gastrointestinal Surgery Department of Yantai Yuhuangding Hospital.The follow-up ended in December 2015.Patients were divided into two groups according to the specialty of physicians who performed the postoperative perigastric lymph node retrieval: the surgeon group(475 cases) and the pathologist group(581 cases).The numbers of positive and total perigastric lymph nodes and the 3- and 5-year survival were compared between gastric cancer patients in the two groups overall and stratified by TNM stage(AJCC 7th Edition).Results: Overall, the numbers of positive and total lymph nodes were significantly higher in the surgeon group than in the pathologist group(6.53±4.07 vs.4.09±3.70, P=0.021; 29.64±11.50 vs.20.71±8.56, P<0.001).Further analysis showed that the total number of lymph nodes in stage Ⅰ patients(19.40±9.62 vs.15.45±8.59, P=0.011) and the numbers of positive and total lymph nodes in stage Ⅱ(1.38±1.08 vs.0.87±1.55, P=0.031; 25.35±10.80 vs.16.75±8.56, P<0.001) and stage Ⅲ patients(8.11±6.91 vs.6.66±5.12, P=0.026; 32.34±12.55 vs.25.45±8.31, P<0.001)were significantly higher in the surgeon group than in the pathologist group.The survival analysis showed that the3- and 5-year survival of stage Ⅱ and Ⅲ patients was significantly higher in the surgeon group than in the pathologist group(82.0% vs.73.1%, 69.5% vs.61.2%, P=0.038; 49.2% vs.38.9%, 36.3% vs.28.0%; P=0.045).Conclusions: Compared with retrieval performed by pathologists, postoperative perigastric lymph node retrieval performed by surgeons was associated with significant increase in the total lymph node number of stage Ⅰ patients, the numbers of positive and total lymph nodes of stage Ⅱ and Ⅲ patients, and the survival of stage Ⅱ and stage Ⅲ gastric cancer patients.
文摘Accidentally swallowed foreign objects are not uncommon but difficult to manage without complications. We describe the case of a 68 year old man who accidentally a swallowed sharp-pointed dental reamer that had reached deep in his jejunum. Double balloon enteroscopic retrieval was performed with polypectomy snare but the reamer was entangled in the wire loop of the snare and penetrated the jejunal wall. After releasing the reamer by pushing and pulling the snare for approximately 30 min, the reamer was retrieved with biopsy forceps. This is the first report of double balloon enteroscopic removal of a dental reamer. Furthermore, this is a novel case with regard to decision making in situations when sharp objects are swallowed.
基金National Key R&D Program of China(2018YFC1507401)Science and Technology Planning Project of Guangdong Province(2017B020244002)+1 种基金National Natural Science Foundation of China(41975138,41705020)Natural Science Foundation of Guangdong Province(2019A1515010814)。
文摘The objective of this research was to acquire a raindrop size distribution(DSDs)retrieved from C-band polarimetric radar observations scheme for the first time in south China.An observation period of the precipitation process was selected,and the shape-slope(μ-Λ)relationship of this region was statistically analyzed using the raindrop sample observations from the two-dimensional video disdrometer(2DVD)at Xinfeng Station,Guangdong Province.Simulated data of the C-band polarimetric radar reflectivity ZHHand differential reflectivity ZDRwere obtained through scattering simulation.The simulation data were combined with DSD fitting to determine the ZDR-Λand log10(ZHH/N0)-Λrelationships.Using Xinfeng C-band polarimetric radar observations ZDRand ZHH,the raindrop Gamma size distribution parametersμ,Λ,and N0were retrieved.A scheme for using C-band polarimetric radar to retrieve the DSDs was developed.This research revealed that during precipitation process,the DSDs obtained using the C-band polarimetric radar retrieval scheme are similar to the 2DVD observations,the precipitation characteristics of rainfall intensity(R),mass-weighted mean diameter(Dm)and intercept parameter(Nw)with time obtained by radar retrieval are basically consistent with the observational results of the 2DVD.This scheme establishes the relationship between the observations of the C-band polarimetric radar and the physical quantities of the numerical model.This method not only can test the prediction of the model data assimilation system on the convective scale and determine error sources,but also can improve the microphysical precipitation processes analysis and radar quantitative precipitation estimation.The present research will facilitate radar data assimilation in the future.
基金National Natural Science Foundation of China(91215302,51278308)Open Project for State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry,Institute of Atmospheric Physics(LAPC)
文摘One-dimensional retrieval was performed on Typhoon Haiyan utilizing the advanced technology microwave sounder onboard the satellite Suomi NPP to retrieve the temperature and water vapor profiles of the typhoon.Comparisons of the retrieved profiles and ECMWF reanalysis were made to assess the results. The main conclusions are as follows.(1) The results have high spatial resolution and therefore can precisely represent the temperature and humidity distribution of the typhoon.(2) The retrieved temperature is low in the areas of low temperature and high in the areas of high temperature; similar patterns are observed for humidity. This means that systematic revision may be needed during routine application.(3) The results of the retrieved temperature and humidity profiles are generally accurate, which is quite important for typhoon monitoring.
基金Qinghai province key laboratory open fund of disaster prevention and reduction(QHKF201401)Key technology projects of China Meteorological Bureau(CMAGJ2014M21)+3 种基金National Natural Science Fund(41675029,41401504,41671425,41565008)Key Scientific Research Projects in Colleges and Universities(17A170005)China Postdoctoral Fund(2016M602232)Foundation of Henan University(2015YBZR020)
文摘Wind shear reflects that the wind field is not uniform, which is one of the primary factors which make the retrieval of the wind field difficult. Based on volume velocity process(VVP) wind field retrieval technique, the intensity of wind shear is identified in this paper. After analyzing the traditional techniques that rely on the difference of radial velocity to identify wind shear, a fixed difference among radial velocities that may cause false identification in a uniform wind field was found. Because of the non-uniformity in wind shear areas, the difference of retrieved results between surrounding analysis volumes can be used as a measurement to show how strong the wind shear is. According to the analysis of a severe convective weather process that occurred in Guangzhou, it can be found that the areas of wind shear appeared with the strength significantly larger than in other regions and the magnitude generally larger than4.5 m/(s·km). Besides, by comparing the variation of wind shear strength during the convection, it can be found that new cells will be more likely to generate when the strength is above 3.0 m/(s·km). Therefore, the analysis of strong wind shear's movement and development is helpful to forecasting severe convections.
基金supported by National Natural Science Foundation of China(Nos.61872370 and 61832017)Beijing Outstanding Young Scientist Program(No.BJJWZYJH012019100020098)Beijing Academy of Artificial Intelligence(BAAI),the Outstanding Innovative Talents Cultivation Funded Programs 2021 of Renmin University of China,and Intelligent Social Governance Platform,Major Innovation&Planning Interdisciplinary Platform for the“Double-First Class”Initiative,Renmin University of China.
文摘Web search provides a promising way for people to obtain information and has been extensively studied.With the surge of deep learning and large-scale pre-training techniques,various neural information retrieval models are proposed,and they have demonstrated the power for improving search(especially,the ranking)quality.All these existing search methods follow a common paradigm,i.e.,index-retrieve-rerank,where they first build an index of all documents based on document terms(i.e.,sparse inverted index)or representation vectors(i.e.,dense vector index),then retrieve and rerank retrieved documents based on the similarity between the query and documents via ranking models.In this paper,we explore a new paradigm of information retrieval without an explicit index but only with a pre-trained model.Instead,all of the knowledge of the documents is encoded into model parameters,which can be regarded as a differentiable indexer and optimized in an end-to-end manner.Specifically,we propose a pre-trained model-based information retrieval(IR)system called DynamicRetriever,which directly returns document identifiers for a given query.Under such a framework,we implement two variants to explore how to train the model from scratch and how to combine the advantages of dense retrieval models.Compared with existing search methods,the model-based IR system parameterizes the traditional static index with a pre-training model,which converts the document semantic mapping into a dynamic and updatable process.Extensive experiments conducted on the public search benchmark Microsoft machine reading comprehension(MS MARCO)verify the effectiveness and potential of our proposed new paradigm for information retrieval.
基金supported by the Fundamental Research Funds for the Central Non-profit Research Institution of the Chinese Academy of Forestry (Grant No.CAFYBB2020ZY003)the Key S&T Project of Inner Mongolia (Grant No.2021ZD0041-001-002)the Central Public-interest Scientific Institution Basal Research Fund (Grant No.11024316000202300001)。
文摘Apricot has a long history of cultivation and has many varieties and types. The traditional variety identification methods are timeconsuming and labor-consuming, posing grand challenges to apricot resource management. Tool development in this regard will help researchers quickly identify variety information. This study photographed apricot fruits outdoors and indoors and constructed a dataset that can precisely classify the fruits using a U-net model (F-score:99%), which helps to obtain the fruit's size, shape, and color features. Meanwhile, a variety search engine was constructed, which can search and identify variety from the database according to the above features. Besides, a mobile and web application (ApricotView) was developed, and the construction mode can be also applied to other varieties of fruit trees.Additionally, we have collected four difficult-to-identify seed datasets and used the VGG16 model for training, with an accuracy of 97%, which provided an important basis for ApricotView. To address the difficulties in data collection bottlenecking apricot phenomics research, we developed the first apricot database platform of its kind (ApricotDIAP, http://apricotdiap.com/) to accumulate, manage, and publicize scientific data of apricot.
文摘The developed system for eye and face detection using Convolutional Neural Networks(CNN)models,followed by eye classification and voice-based assistance,has shown promising potential in enhancing accessibility for individuals with visual impairments.The modular approach implemented in this research allows for a seamless flow of information and assistance between the different components of the system.This research significantly contributes to the field of accessibility technology by integrating computer vision,natural language processing,and voice technologies.By leveraging these advancements,the developed system offers a practical and efficient solution for assisting blind individuals.The modular design ensures flexibility,scalability,and ease of integration with existing assistive technologies.However,it is important to acknowledge that further research and improvements are necessary to enhance the system’s accuracy and usability.Fine-tuning the CNN models and expanding the training dataset can improve eye and face detection as well as eye classification capabilities.Additionally,incorporating real-time responses through sophisticated natural language understanding techniques and expanding the knowledge base of ChatGPT can enhance the system’s ability to provide comprehensive and accurate responses.Overall,this research paves the way for the development of more advanced and robust systems for assisting visually impaired individuals.By leveraging cutting-edge technologies and integrating them into amodular framework,this research contributes to creating a more inclusive and accessible society for individuals with visual impairments.Future work can focus on refining the system,addressing its limitations,and conducting user studies to evaluate its effectiveness and impact in real-world scenarios.
基金funded by National Key Research and Development Program of China (2022YFB2804603,2022YFB2804604)National Natural Science Foundation of China (62075096,62205147,U21B2033)+7 种基金China Postdoctoral Science Foundation (2023T160318,2022M711630,2022M721619)Jiangsu Funding Program for Excellent Postdoctoral Talent (2022ZB254)The Leading Technology of Jiangsu Basic Research Plan (BK20192003)The“333 Engineering”Research Project of Jiangsu Province (BRA2016407)The Jiangsu Provincial“One belt and one road”innovation cooperation project (BZ2020007)Open Research Fund of Jiangsu Key Laboratory of Spectral Imaging&Intelligent Sense (JSGP202105)Fundamental Research Funds for the Central Universities (30922010405,30921011208,30920032101,30919011222)National Major Scientific Instrument Development Project (62227818).
文摘Recently,deep learning has yielded transformative success across optics and photonics,especially in optical metrology.Deep neural networks (DNNs) with a fully convolutional architecture (e.g.,U-Net and its derivatives) have been widely implemented in an end-to-end manner to accomplish various optical metrology tasks,such as fringe denoising,phase unwrapping,and fringe analysis.However,the task of training a DNN to accurately identify an image-to-image transform from massive input and output data pairs seems at best naive,as the physical laws governing the image formation or other domain expertise pertaining to the measurement have not yet been fully exploited in current deep learning practice.To this end,we introduce a physics-informed deep learning method for fringe pattern analysis (PI-FPA) to overcome this limit by integrating a lightweight DNN with a learning-enhanced Fourier transform profilometry (Le FTP) module.By parameterizing conventional phase retrieval methods,the Le FTP module embeds the prior knowledge in the network structure and the loss function to directly provide reliable phase results for new types of samples,while circumventing the requirement of collecting a large amount of high-quality data in supervised learning methods.Guided by the initial phase from Le FTP,the phase recovery ability of the lightweight DNN is enhanced to further improve the phase accuracy at a low computational cost compared with existing end-to-end networks.Experimental results demonstrate that PI-FPA enables more accurate and computationally efficient single-shot phase retrieval,exhibiting its excellent generalization to various unseen objects during training.The proposed PI-FPA presents that challenging issues in optical metrology can be potentially overcome through the synergy of physics-priors-based traditional tools and data-driven learning approaches,opening new avenues to achieve fast and accurate single-shot 3D imaging.
基金Under the auspices of the Social Science and Humanity on Young Fund of the Ministry of Education of China(No.21YJCZH100)the Scientific Research Project on Outstanding Young of the Fujian Agriculture and Forestry University(No.XJQ201920)+1 种基金the Science and Technology Innovation Special Fund Project of Fujian Agriculture and Forestry University(No.CXZX2021032)the Forestry Peak Discipline Construction Project of Fujian Agriculture and Forestry University(No.72202200205)。
文摘Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human settlements,it is significant for exploring the evolution characteristics of urban thermal environment and analyzing its driving forces.Taking the Landsat series images as the basic data sources,the winter land surface temperature(LST)of the rapid urbanization area of Fuzhou City in China was quantitatively retrieved from 2001 to 2021.Combing comprehensively the standard deviation ellipse model,profile analysis and GeoDetector model,the spatio-temporal evolution characteristics and influencing factors of the winter urban thermal environment were systematically analyzed.The results showed that the winter LST presented an increasing trend in the study area during 2001–2021,and the winter LST of the central urban regions was significantly higher than the suburbs.There was a strong UHI effect from 2001 to 2021with an expansion trend from the central urban regions to the suburbs and coastal areas in space scale.The LST of green lands and wetlands are significantly lower than croplands,artificial surface and unvegetated lands.Vegetation and water bodies had a significant mitigation effect on UHI,especially in the micro-scale.The winter UHI had been jointly driven by the underlying surface and socio-economic factors in a nonlinear or two-factor interactive enhancement mode,and socio-economic factors had played a leading role.This research could provide data support and decision-making references for rationally planning urban layout and promoting sustainable urban development.
文摘Background A medical content-based image retrieval(CBIR)system is designed to retrieve images from large imaging repositories that are visually similar to a user′s query image.CBIR is widely used in evidence-based diagnosis,teaching,and research.Although the retrieval accuracy has largely improved,there has been limited development toward visualizing important image features that indicate the similarity of retrieved images.Despite the prevalence of 3D volumetric data in medical imaging such as computed tomography(CT),current CBIR systems still rely on 2D cross-sectional views for the visualization of retrieved images.Such 2D visualization requires users to browse through the image stacks to confirm the similarity of the retrieved images and often involves mental reconstruction of 3D information,including the size,shape,and spatial relations of multiple structures.This process is time-consuming and reliant on users'experience.Methods In this study,we proposed an importance-aware 3D volume visualization method.The rendering parameters were automatically optimized to maximize the visibility of important structures that were detected and prioritized in the retrieval process.We then integrated the proposed visualization into a CBIR system,thereby complementing the 2D cross-sectional views for relevance feedback and further analyses.Results Our preliminary results demonstrate that 3D visualization can provide additional information using multimodal positron emission tomography and computed tomography(PETCT)images of a non-small cell lung cancer dataset.
基金Nursing Research Outcome of the Pilot Project for Course Assessment Reform in Sanya University(Project number:SYJGKH2022138)。
文摘Objective:This paper aims to evaluate the implementation effect of the diversified course assessment method reform.Methods:A diversified assessment method was implemented for 196 undergraduate nursing students.Students’mastery of key knowledge in“Nursing Research”was assessed through group reports on topic selection and literature retrieval,as well as the proposition level of the final examination.Results:81.6%of the students agreed with the course assessment method,and 97.9%believed studying“Nursing Research”would be helpful for future scientific research applications.Conclusion:Diversified assessment methods can help improve undergraduate nursing students’scientific research skills and comprehensive quality.
文摘The task of indoor visual localization, utilizing camera visual information for user pose calculation, was a core component of Augmented Reality (AR) and Simultaneous Localization and Mapping (SLAM). Existing indoor localization technologies generally used scene-specific 3D representations or were trained on specific datasets, making it challenging to balance accuracy and cost when applied to new scenes. Addressing this issue, this paper proposed a universal indoor visual localization method based on efficient image retrieval. Initially, a Multi-Layer Perceptron (MLP) was employed to aggregate features from intermediate layers of a convolutional neural network, obtaining a global representation of the image. This approach ensured accurate and rapid retrieval of reference images. Subsequently, a new mechanism using Random Sample Consensus (RANSAC) was designed to resolve relative pose ambiguity caused by the essential matrix decomposition based on the five-point method. Finally, the absolute pose of the queried user image was computed, thereby achieving indoor user pose estimation. The proposed indoor localization method was characterized by its simplicity, flexibility, and excellent cross-scene generalization. Experimental results demonstrated a positioning error of 0.09 m and 2.14° on the 7Scenes dataset, and 0.15 m and 6.37° on the 12Scenes dataset. These results convincingly illustrated the outstanding performance of the proposed indoor localization method.
基金supported by "CE-1" Lunar Microwave Sounder Program
文摘Lunar regolith parameters, such as physical temperature, thickness and dielectric constant, are important in studying regolith features, distribution of lunar resources and evolution of the Moon. There had been no measurement obtained by lunar-orbit-borne microwave radiometer applied to evaluate the properties of lunar regolith before CE-1 Lunar Microwave Sounder (CELMS) being launched. CEMLS is the first passive microwave radiometer in the world to sound the surface of the Moon. The brightness temperatures (TB) sensed by CELMS include complicated information on the above geophysical parameters. In this paper, algorithms of retrieving dielectric constant, regolith thickness, and 3He content from CELMS brightness temperatures are developed, and the results are compared with those from literature. The results show that the regolith thicknesses are mostly in the range of 4.0-6.0 m, and 43% of them are bigger than 5.0 m. The content of 3He evaluated by retrieved regolith thickness is about 1.03 million tons.
基金Supported by the China Meteorological Administration Special Public Welfare Research Fund for the Third Tibetan Plateau Atmospheric Science Experiment(GYHY201406001)National Natural Science Foundation of China(41605107 and 91437104)Basic Research Fund of Chinese Academy of Meteorological Sciences(2015Y006)
文摘In order to improve understanding of deep convective clouds over the Tibetan Plateau, characteristics of vertical structure of a deep strong convective cloud over Naqu station and a deep weak convective cloud approximately 100 km to the west of Naqu station, which occurred over 1300-1600 Beijing Time (BT) 9 July 2014 during the Third Tibetan Plateau Atmospheric Science Experiment (TIPEX-Ⅲ), are analyzed, based on multi-source satellite data from TRMM, CloudSat, and Aqua, and radar data from ground-based vertically pointing radars (C-band frequency-modulated continuous-wave radar and KA-band millimeter wave cloud radar). The results are as follows.(1) The horizontal scales of both the deep strong and deep weak convective clouds were small (10-20 km), and their tops were high[15-16 km above sea level (ASL)]. Across the level of 0℃ isotherm in the deep strong convective cloud, the reflectivity increased rapidly, suggesting that the melting process of solid precipitation particles through the 0℃ level played an important role. A bright band located at 5.5 km ASL (i.e., 1 km above ground level) appeared during the period of convection weakening.(2) The reflectivity values from TRMM precipitation radar below 11 km were found to be overestimated compared to those derived from the C-band frequency-modulated continuous-wave radar.(3) Deep convective clouds were mainly ice clouds, and there were rich small ice particles above 10 km, while few large ice particles were found below 10 km. The microphysical processes of deep strong and deep weak convective clouds mainly included mixed-phase process and glaciated process, and the mixed-phase process can be divided into two types:one was the rimming process below the level of -25℃(deep strong convective cloud) or -29℃(deep weak convective cloud) and the other was aggregation and deposition process above that level. The latter process was accompanied with fast increase in ice particle effective radius. The above evidence from space-based and ground-based observational data further clarify the characteristics of vertical structure of deep convective clouds over the Tibetan Plateau, and provide a basis for the evaluation of simulation results of deep convective clouds by cloud models.
文摘In this paper, we show that to retrieve specified objects in massive remote sensing data set is very important in both practice and theory. An algorithm-based content retrieval in the massive data set is studied. To avoid the loss of information, the algorithm based on the Support Vector Machine classification is proposed. Also, the experiment on the real data set is made.