期刊文献+
共找到40,278篇文章
< 1 2 250 >
每页显示 20 50 100
基于Guided BERTopic模型的产业链关键核心技术识别与发展趋势研判--以未来工业互联网为例
1
作者 陈升 杨恒 张楠 《科学管理研究》 CSSCI 北大核心 2024年第3期35-44,共10页
产业链关键核心技术不仅是国之重器,而且对推动我国经济的高质量发展和保障国家安全起着至关重要的作用。当前,工业互联网产业链的关键技术发展成为我国的研究重点,该领域的重要性在2023年被提升至国家级重大研究计划。综合收集了1989-2... 产业链关键核心技术不仅是国之重器,而且对推动我国经济的高质量发展和保障国家安全起着至关重要的作用。当前,工业互联网产业链的关键技术发展成为我国的研究重点,该领域的重要性在2023年被提升至国家级重大研究计划。综合收集了1989-2024年中美两国在工业互联网领域的专利数据,基于《关键和新兴技术清单》和《未来工业互联网基础理论与关键技术重大研究计划》,构建了一套工业互联网产业链核心关键技术的种子词库。利用Guided BERTopic模型提取了产业链关键技术主题,并采用Logistic模型评估了这些技术的生命周期,进而对比中美两国的发展情况,提出了针对未来发展的建议。研究结果表明,相比美国,我国在大多数产业链核心技术方面仍处于成长阶段,而美国则已步入技术饱和阶段。展望未来,设备监测系统、设备管理系统、无线通信技术及能耗监测分析系统等被认为是具有巨大发展潜力的技术。研究提出了一种基于政策文件的产业链关键技术识别方法,并通过对工业互联网专利技术的实证分析,为制定相关政策提供了科学指导和建议。 展开更多
关键词 guided BERTopic模型 产业链核心关键技术 工业互联网 中美比较 专利文本 LOGISTIC模型
下载PDF
Guided Care护理模式对老年骨质疏松症患者自我管理能力和生活质量的影响
2
作者 周晓英 袭玉荣 《中外医疗》 2024年第16期169-173,共5页
目的探讨分析Guided Care护理模式对老年骨质疏松症患者自我管理能力和生活质量的影响。方法简单随机选取2022年1月—2023年9月山东省泰安荣军医院收治的60例老年骨质疏松症患者为研究对象,按随机数表法将其分为常规组(实施常规护理干... 目的探讨分析Guided Care护理模式对老年骨质疏松症患者自我管理能力和生活质量的影响。方法简单随机选取2022年1月—2023年9月山东省泰安荣军医院收治的60例老年骨质疏松症患者为研究对象,按随机数表法将其分为常规组(实施常规护理干预),模式组(在常规组的基础上给予Guided Care护理模式干预),每组30例,两组均持续干预2个月,比较两组患者干预前后的健康认知水平、跌倒风险、自我管理能力、生活质量、护理满意度。结果干预2个月后,模式组的健康认知水平评分高于常规组,差异有统计学意义(P<0.05)。干预2个月后,模式组的跌倒风险评分低于常规组,差异有统计学意义(P<0.05)。干预2个月后,模式组的自我管理能力评分高于常规组,生活质量评分低于常规组,差异有统计学意义(P均<0.05)。干预2个月后,模式组的护理满意度为93.33%,高于常规组的护理满意度73.33%,差异有统计学意义(χ^(2)=4.320,P<0.05)。结论在老年骨质疏松症患者中,应用Guided Care护理模式,可以有效地提升患者的健康认知水平及自我管理能力,提高患者的生活质量,降低患者跌倒的风险。 展开更多
关键词 guided Care护理模式 老年骨质疏松症 自我管理能力 生活质量
下载PDF
Pipeline thickness estimation using the dispersion of higher-order SH guided waves
3
作者 代政辰 刘金霞 +3 位作者 龙云飞 张建海 Tribikram Kundu 崔志文 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期389-396,共8页
Thickness measurement plays an important role in the monitoring of pipeline corrosion damage. However, the requirement for prior knowledge of the shear wave velocity in the pipeline material for popular ultrasonic thi... Thickness measurement plays an important role in the monitoring of pipeline corrosion damage. However, the requirement for prior knowledge of the shear wave velocity in the pipeline material for popular ultrasonic thickness measurement limits its widespread application. This paper proposes a method that utilizes cylindrical shear horizontal(SH) guided waves to estimate pipeline thickness without prior knowledge of shear wave velocity. The inversion formulas are derived from the dispersion of higher-order modes with the high-frequency approximation. The waveform of the example problems is simulated using the real-axis integral method. The data points on the dispersion curves are processed in the frequency domain using the wave-number method. These extracted data are then substituted into the derived formulas. The results verify that employing higher-order SH guided waves for the evaluation of thickness and shear wave velocity yields less than1% error. This method can be applied to both metallic and non-metallic pipelines, thus opening new possibilities for health monitoring of pipeline structures. 展开更多
关键词 pipeline wall thickness higher-order modes SH guided waves DISPERSION
下载PDF
Detection of internal crack growth in polyethylene pipe using guided wave ultrasonic testing
4
作者 Jay Kumar Shah Hao Wang Said El-Hawwat 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期319-329,共11页
Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively unexplored.The growth of internal cracks in PE pipe seve... Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively unexplored.The growth of internal cracks in PE pipe severely affects its pressure-holding capacity,hence the early detection of internal cracks is crucial for effective pipeline maintenance strategies.This study extends the scope of guided wave-based ultrasonic testing to detect the growth of internal cracks in a natural gas distribution PE pipe.Laboratory experiments and a finite element model were planned to study the wave-crack interaction at different stages of axially oriented internal crack growth with a piezoceramic transducer-based setup arranged in a pitch-catch configuration.Mode dispersion analysis supplemented with preliminary experiments was performed to isolate the optimal inspection frequency,leading to the selection of the T(0,1)mode at 50-kHz for the investigation.A transmission index based on the energy of the T(0,1)mode was developed to trace the extent of simulated crack growth.The findings revealed an inverse linear correlation between the transmission index and the crack depth for crack growth beyond 20%crack depth. 展开更多
关键词 polyethylene pipes internal cracks guided wave ultrasonic testing torsional modes finite element modeling
下载PDF
An Effective Optimization Method for Integrated Scheduling of Multiple Automated Guided Vehicle Problems
5
作者 Hongyan Sang Zhongkai Li M.Fatih Tasgetiren 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2024年第5期1355-1367,共13页
Automated Guided Vehicle(AGV)scheduling problem is an emerging research topic in the recent literature.This paper studies an integrated scheduling problem comprising task assignment and path planning for AGVs.To reduc... Automated Guided Vehicle(AGV)scheduling problem is an emerging research topic in the recent literature.This paper studies an integrated scheduling problem comprising task assignment and path planning for AGVs.To reduce the transportation cost of AGVs,this work also proposes an optimization method consisting of the total running distance,total delay time,and machine loss cost of AGVs.A mathematical model is formulated for the problem at hand,along with an improved Discrete Invasive Weed Optimization algorithm(DIWO).In the proposed DIWO algorithm,an insertion-based local search operator is developed to improve the local search ability of the algorithm.A staggered time departure heuristic is also proposed to reduce the number of AGV collisions in path planning.Comprehensive experiments are conducted,and 100 instances from actual factories have proven the effectiveness of the optimization method. 展开更多
关键词 Automated guided Vehicle(AGV) integrated scheduling staggered time departure heuristics
原文传递
Research on the navigation method of large-scale differential tail-control improvised guided munitions based on rotational speed constraints
6
作者 Ning Liu Wenjiang Zhao +4 位作者 Yao Wang Kai Shen Zhong Su Wenhao Qi Yuedong Xie 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第8期155-170,共16页
In the process of launching guided projectile under the conventional system, it is difficult to effectively obtain the precise navigation parameters of the projectile in the high dynamic environment. Aiming at this pr... In the process of launching guided projectile under the conventional system, it is difficult to effectively obtain the precise navigation parameters of the projectile in the high dynamic environment. Aiming at this problem, this paper describes a new system of guided ammunition based on tail spin reduction. After analyzing the mechanism of the ammunition's tail spin reduction, a navigation method of large scale difference tail control simple guided ammunition based on speed constraint is proposed. In this method,the corresponding navigation constraints can be carried out by combining the rotation speed state of the ammunition itself, and the optimal solution of navigation parameters during the flight of the missile can be obtained by Extended Kalman Filter(EKF). Finally, the performance of the proposed method was verified by the simulation environment, and the hardware-in-the-loop simulation test and flight test were carried out to verify the performance of the method in the real environment. The experimental results show that the proposed method can achieve the optimal estimation of navigation parameters for simple guided ammunition with large-scale difference tail control. Under the conditions of simulation test and hardware-in-loop simulation test, the position and velocity errors calculated by the method in this paper converged. Under the condition of flight test, the spatial average error calculated by the method described in this paper is 6.17 m, and the spatial error of the final landing point is 3.50 m.Through this method, the accurate acquisition of navigation parameters in the process of projectile launching is effectively realized. 展开更多
关键词 guided projectiles Tail spin reduction RPM constraints Combined navigation Extended Kalman filter(EKF)
下载PDF
Role of endoscopic ultrasound-guided biliary drainage for palliation of malignant biliary obstruction
7
作者 Sahib Singh Saurabh Chandan Antonio Facciorusso 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第8期2369-2373,共5页
Endoscopic ultrasound-guided biliary drainage(EUS-BD)directs bile flow into the digestive tract and has been mostly used in patients with malignant biliary obstruction(MBO)where endoscopic retrograde cholangiopancreat... Endoscopic ultrasound-guided biliary drainage(EUS-BD)directs bile flow into the digestive tract and has been mostly used in patients with malignant biliary obstruction(MBO)where endoscopic retrograde cholangiopancreatography-guided biliary drainage was unsuccessful or was not feasible.Lumen apposing metal stents(LAMS)are deployed during EUS-BD,with the newer electrocautery-enhanced LAMS reducing procedure time and complication rates due to the inbuilt cautery at the catheter tip.EUS-BD with electrocautery-enhanced LAMS has high technical and clinical success rates for palliation of MBO,with bleeding,cholangitis,and stent occlusion being the most common adverse events.Recent studies have even suggested comparable efficacy between EUS-BD and endosc-opic retrograde cholangiopancreatography as the primary approach for distal MBO.In this editorial,we commented on the article by Peng et al published in the recent issue of the World Journal of Gastrointestinal Surgery in 2024. 展开更多
关键词 Endoscopic ultrasound Endoscopic ultrasound guided biliary drainage CANCER PANCREAS Bile duct ENDOSCOPY
下载PDF
Research on High-Velocity Impact Damage Monitoring Method of CFRP Based on Guided Wave
8
作者 WANG Yang YANG Xiaofei +1 位作者 QIU Lei YUAN Shenfang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期60-69,共10页
Carbon fiber-reinforced polymer(CFRP)is widely used in aerospace applications.This kind of material may face the threat of high-velocity impact in the process of dedicated service,and the relevant research mainly cons... Carbon fiber-reinforced polymer(CFRP)is widely used in aerospace applications.This kind of material may face the threat of high-velocity impact in the process of dedicated service,and the relevant research mainly considers the impact resistance of the material,and lacks the high-velocity impact damage monitoring research of CFRP.To solve this problem,a real high-velocity impact damage experiment and structural health monitoring(SHM)method of CFRP plate based on piezoelectric guided wave is proposed.The results show that CFRP has obvious perforation damage and fiber breakage when high-velocity impact occurs.It is also proved that guided wave SHM technology can be effectively used in the monitoring of such damage,and the damage can be reflected by quantifying the signal changes and damage index(DI).It provides a reference for further research on guided wave structure monitoring of high/hyper-velocity impact damage of CFRP. 展开更多
关键词 guided waves structural health monitoring(SHM) carbon fiber reinforced polymer(CFRP) high-velocity impact
下载PDF
Clinical Efficacy of GBR Technique Combined with Temporary Bridgework-Guided Gingival Contouring in Treating Upper Anterior Tooth Loss with Labial Bone Defects
9
作者 Yu Ma Jirui Ma 《Journal of Clinical and Nursing Research》 2024年第6期171-176,共6页
Objective:To investigate the clinical effect of the guided bone regeneration(GBR)technique combined with temporary bridgework-guided gingival contouring in treating upper anterior tooth loss with labial bone defects.M... Objective:To investigate the clinical effect of the guided bone regeneration(GBR)technique combined with temporary bridgework-guided gingival contouring in treating upper anterior tooth loss with labial bone defects.Methods:From July 2023 to April 2024,80 patients with upper anterior tooth loss and labial bone defects were admitted to the hospital and selected as evaluation samples.They were divided into an observation group(n=40)and a control group(n=40)using a numerical table lottery scheme.The control group received treatment with the GBR technique,while the observation group received treatment with the GBR technique combined with temporary bridges to guide gingival contouring.The two groups were compared in terms of clinical red aesthetic scores(PES),labial alveolar bone density,labial bone wall thickness,gingival papillae,gingival margin levels,and patient satisfaction.Results:The PES scores of patients in the observation group were higher than those in the control group after surgery(P<0.05).The bone density of the labial alveolar bone and the thickness of the labial bone wall in the observation group were higher than those in the control group.The levels of gingival papillae and gingival margins were lower in the observation group after surgery(P<0.05).Additionally,patient satisfaction in the observation group was higher than in the control group(P<0.05).Conclusion:The GBR technique combined with temporary bridge-guided gingival contouring for treating upper anterior tooth loss with labial bone defects can improve the aesthetic effect of gingival soft tissue,increase alveolar bone density and the thickness of the labial bone wall,and enhance patient satisfaction.This approach is suitable for widespread application in healthcare institutions. 展开更多
关键词 Upper anterior teeth loss Labial bone defects guided bone regeneration(GBR)technique Temporary bridgework-guided gingival contouring
下载PDF
Comparison of Cognitive Registration Transrectal Ultrasound-Guided Targeted Biopsy of Prostate to Systematic 12-Core Biopsy: A Retrospective, Multicentre Study
10
作者 Kevin Chang Yue Wei Lee Say Bob +4 位作者 Devindran Manoharan Liong Men Long Teoh Sze Yong Teo Rui Ling Chua Zi Wei 《Open Journal of Urology》 2024年第7期381-390,共10页
Introduction: Prostate cancer (PCa) is the third most prevalent cancer among Malaysian males, often diagnosed at advanced stages, leading to suboptimal outcomes. While transrectal ultrasound-guided systematic biopsy (... Introduction: Prostate cancer (PCa) is the third most prevalent cancer among Malaysian males, often diagnosed at advanced stages, leading to suboptimal outcomes. While transrectal ultrasound-guided systematic biopsy (TRUS-SB) is the primary diagnostic method, prebiopsy multiparametric magnetic resonance imaging (mpMRI) is gaining popularity in identifying suspicious lesions. This study addresses the lack of comprehensive investigations into the efficacy of cognitive registration TRUS targeted biopsy (COG-TB) compared to conventional TRUS-SB, considering the resource limitations of the Malaysian healthcare system. Materials and Methods: A retrospective cohort study was conducted in two Malaysian healthcare facilities. 116 adult patients with a prostate-specific antigen (PSA) level of more than 4 ng/mL who underwent both COG-TB and TRUS-SB between October 2020 and March 2022 were included. Primary outcomes were cancer detection rate and histopathological outcomes, including Gleason score. Results: COG-TB showed a higher overall cancer detection rate (50%) compared to TRUS-SB (44%). Clinically significant cancer detection rates were similar between COG-TB and TRUS-SB (37.1%). Further analysis revealed that both COG-TB and TRUS-SB detected clinically significant cancer in 30.2% of patients, did not detect it in 56.0%, and had conflicting findings in 16 patients (p Conclusion: COG-TB and TRUS-SB have comparable detection rates for clinically significant prostate cancer, with COG-TB showing a higher tendency to detect insignificant prostate cancer. Further studies comparing these methods are warranted. 展开更多
关键词 Prostate Cancer Multiparametric MRI Targeted Biopsy Cognitive Fusion Transrectal Ultrasound-guided Biopsy
下载PDF
基于SSI-GuidedLDA模型的引导式网络敏感信息识别研究 被引量:2
11
作者 吴树芳 杨强 +1 位作者 侯晓舟 尹萌 《情报杂志》 CSSCI 北大核心 2023年第11期119-125,共7页
[研究目的]引导式主题模型可以引导生成有倾向性的敏感主题,提高网络敏感信息识别性能,对维护国家安全和社会稳定具有重要意义。[研究方法]针对当前网络敏感信息识别研究构建敏感信息特征不全面和不准确,从而导致识别性能欠佳的问题,提... [研究目的]引导式主题模型可以引导生成有倾向性的敏感主题,提高网络敏感信息识别性能,对维护国家安全和社会稳定具有重要意义。[研究方法]针对当前网络敏感信息识别研究构建敏感信息特征不全面和不准确,从而导致识别性能欠佳的问题,提出基于SSI-GuidedLDA模型的引导式网络敏感信息识别方法。首先,从多源网络资源中爬取敏感种子词,并基于词向量模型Word2Vec获得种子词的敏感语义相关词,构建更为完备、准确的敏感特征。其次,将构建的敏感特征融入引导式主题模型,得到改进后的模型SSI-GuidedLDA。最后,基于SSI-GuidedLDA模型获得待识别信息的主题分布,通过主题分布概率判断其是否为网络敏感信息。[研究结论]在新浪微博数据集上的实验结果显示,与已有方法相比,提出的方法在准确率、召回率和F 1值上均有一定提高。 展开更多
关键词 敏感语义(SSI) 敏感种子词 敏感信息识别 引导式主题模型 guidedLDA Word2Vec
下载PDF
Guided Care护理对接受体外受精-胚胎移植的肥胖型多囊卵巢综合征不孕患者的干预效果 被引量:6
12
作者 闫冰 刘媛 +3 位作者 张平 高云 梁琳琳 常琼 《河南医学研究》 CAS 2023年第11期2089-2092,共4页
目的 评价Guided Care护理方案对接受体外受精-胚胎移植(IVF-ET)助孕的肥胖型多囊卵巢综合征(PCOS)患者的干预效果。方法 选择2022年1—12月在河南省人民医院生殖中心接受IVF-ET助孕的74例肥胖型PCOS患者作为研究对象,按随机数表法分为... 目的 评价Guided Care护理方案对接受体外受精-胚胎移植(IVF-ET)助孕的肥胖型多囊卵巢综合征(PCOS)患者的干预效果。方法 选择2022年1—12月在河南省人民医院生殖中心接受IVF-ET助孕的74例肥胖型PCOS患者作为研究对象,按随机数表法分为观察组(37例)和对照组(37例)。对照组患者接受常规护理,观察组在常规护理基础上接受Guided Care护理。比较两组患者治疗依从性、生活方式及焦虑程度。结果 Guided Care护理可提高患者的就医及服药依从性,改善其生活方式,降低患者的焦虑程度(P<0.05)。结论 Guided Care护理方案可以改善肥胖型PCOS患者的治疗依从性及其生活方式,降低患者的焦虑程度。 展开更多
关键词 多囊卵巢综合征 体外受精-胚胎移植 guided Care护理
下载PDF
Application of Automated Guided Vehicles in Smart Automated Warehouse Systems:A Survey 被引量:5
13
作者 Zheng Zhang Juan Chen Qing Guo 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第3期1529-1563,共35页
Automated Guided Vehicles(AGVs)have been introduced into various applications,such as automated warehouse systems,flexible manufacturing systems,and container terminal systems.However,few publications have outlined pr... Automated Guided Vehicles(AGVs)have been introduced into various applications,such as automated warehouse systems,flexible manufacturing systems,and container terminal systems.However,few publications have outlined problems in need of attention in AGV applications comprehensively.In this paper,several key issues and essential models are presented.First,the advantages and disadvantages of centralized and decentralized AGVs systems were compared;second,warehouse layout and operation optimization were introduced,including some omitted areas,such as AGVs fleet size and electrical energy management;third,AGVs scheduling algorithms in chessboardlike environments were analyzed;fourth,the classical route-planning algorithms for single AGV and multiple AGVs were presented,and some Artificial Intelligence(AI)-based decision-making algorithms were reviewed.Furthermore,a novel idea for accelerating route planning by combining Reinforcement Learning(RL)andDijkstra’s algorithm was presented,and a novel idea of the multi-AGV route-planning method of combining dynamic programming and Monte-Carlo tree search was proposed to reduce the energy cost of systems. 展开更多
关键词 Automated guided vehicles(AGVs) smart automated warehouse systems AGVs scheduling AGVs route planning artificial intelligence(AI)
下载PDF
A greedy path planning algorithm based on pre-path-planning and real-time-conflict for multiple automated guided vehicles in large-scale outdoor scenarios 被引量:2
14
作者 王腾达 WU Wenjun +2 位作者 YANG Feng SUN Teng GAO Qiang 《High Technology Letters》 EI CAS 2023年第3期279-287,共9页
With the wide application of automated guided vehicles(AGVs) in large scale outdoor scenarios with complex terrain,the collaborative work of a large number of AGVs becomes the main trend.The effective multi-agent path... With the wide application of automated guided vehicles(AGVs) in large scale outdoor scenarios with complex terrain,the collaborative work of a large number of AGVs becomes the main trend.The effective multi-agent path finding(MAPF) algorithm is urgently needed to ensure the efficiency and realizability of the whole system. The complex terrain of outdoor scenarios is fully considered by using different values of passage cost to quantify different terrain types. The objective of the MAPF problem is to minimize the cost of passage while the Manhattan distance of paths and the time of passage are also evaluated for a comprehensive comparison. The pre-path-planning and real-time-conflict based greedy(PRG) algorithm is proposed as the solution. Simulation is conducted and the proposed PRG algorithm is compared with waiting-stop A^(*) and conflict based search(CBS) algorithms. Results show that the PRG algorithm outperforms the waiting-stop A^(*) algorithm in all three performance indicators,and it is more applicable than the CBS algorithm when a large number of AGVs are working collaboratively with frequent collisions. 展开更多
关键词 automated guided vehicle(AGV) multi-agent path finding(MAPF) complex terrain greedy algorithm
下载PDF
Comparison of Transrectal Prostate Digital and Ultrasound-Guided Core Biopsies in 400 Men in a Low-and-Middle Income Country
15
作者 Junior Barthelemy Mekeme Mekeme Oriol Landry Mbouche +15 位作者 Figuim Bello Bright Che Awondo Aurele Achille Mbassi Cedrick Jean Fouda Tax Liendi Marcella Biyouma Guillaume Gayma Marcel Junior Yon Mekeme Junior Ngue Ngue Mabah Paul Adrien Atangana Pierre Ongolo Zogo Pierre Joseph Fouda Noel Coulibaly Angwafo III Fru Maurice Aurelien Sosso 《Open Journal of Urology》 2023年第10期418-432,共15页
Background: The diagnosis of prostate cancer (PCa) relies on clinical assessment with digital rectal examination, serum PSA and histological examination. Limitations in our technical facilities, high financial cost of... Background: The diagnosis of prostate cancer (PCa) relies on clinical assessment with digital rectal examination, serum PSA and histological examination. Limitations in our technical facilities, high financial cost of ultrasound-guided biopsy often prevent us from implementing the guidelines on the practice of prostate biopsy. Methods: We conducted a retrospective and cross-sectional descriptive study comparing digital-guided and ultrasound-guided transrectal prostate biopsy of 400 patients over a period of 12 years in the Yaounde Central Hospital. We reviewed files of patients who underwent digital and ultrasound guided biopsy procedures. Data was analyzed using EPI info 7.0. Parametric variables were reported as means and standard deviations and percentages and counts were used to report categorical variables. Results: Out of the 400 patients, 292 digital-guided transrectal biopsies (73%) and 108 ultrasound-guided transrectal biopsies (27%) were performed in patients who were suspected of having prostate cancer (PCa). Patients were aged between 39 to 90 years. Both procedures were effective in identifying prostate cancer. Gleason score between 2 to 10 detected prostate adenocarcinoma for 301 patients (75.2%). The complications included anal pain, rectal bleeding, hematuria and urinary tract infections, with an occurrence rate similar for both ultrasound-guided (2.25%) and digitally-guided techniques (2.5%). Seven patients (1.75%) required hospitalization for management of complications. The mortality rate was null. Conclusion: Both techniques are effective in detecting PCa with the similar complication rates. Digital-guided trans-rectal prostate biopsy still has its place in a resource-limited setting like ours. 展开更多
关键词 PROSTATE Biopsy Digital guided Ultrasound guided ADENOCARCINOMA Gleason Score
下载PDF
Guided Dropout: Improving Deep Networks Without Increased Computation
16
作者 Yifeng Liu Yangyang Li +3 位作者 Zhongxiong Xu Xiaohan Liu Haiyong Xie Huacheng Zeng 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期2519-2528,共10页
Deep convolution neural networks are going deeper and deeper.How-ever,the complexity of models is prone to overfitting in training.Dropout,one of the crucial tricks,prevents units from co-adapting too much by randomly... Deep convolution neural networks are going deeper and deeper.How-ever,the complexity of models is prone to overfitting in training.Dropout,one of the crucial tricks,prevents units from co-adapting too much by randomly drop-ping neurons during training.It effectively improves the performance of deep net-works but ignores the importance of the differences between neurons.To optimize this issue,this paper presents a new dropout method called guided dropout,which selects the neurons to switch off according to the differences between the convo-lution kernel and preserves the informative neurons.It uses an unsupervised clus-tering algorithm to cluster similar neurons in each hidden layer,and dropout uses a certain probability within each cluster.Thereby this would preserve the hidden layer neurons with different roles while maintaining the model’s scarcity and gen-eralization,which effectively improves the role of the hidden layer neurons in learning the features.We evaluated our approach compared with two standard dropout networks on three well-established public object detection datasets.Experimental results on multiple datasets show that the method proposed in this paper has been improved on false positives,precision-recall curve and average precision without increasing the amount of computation.It can be seen that the increased performance of guided dropout is thanks to shallow learning in the net-works.The concept of guided dropout would be beneficial to the other vision tasks. 展开更多
关键词 Neural network guided dropout object detection shallow learning
下载PDF
Propagation Characteristics of Ultrasonic Guided Waves in Grouted Rockbolt Systems with Bond Defects under Different Confining Conditions
17
作者 Shuisheng Yu Jin Chen +2 位作者 Yawei Wang Honghao Yang Shucan Lu 《Journal of Modern Physics》 CAS 2023年第5期722-740,共19页
A rockbolt acting in the rock mass is subjected to the combined action of the pull-out load and confining pressure, and the bond quality of the rockbolt directly affects the stability of the roadway and cavern. Theref... A rockbolt acting in the rock mass is subjected to the combined action of the pull-out load and confining pressure, and the bond quality of the rockbolt directly affects the stability of the roadway and cavern. Therefore, in this study, confining pressure and pull-out load are applied to grouted rockbolt systems with bond defects by a numerical simulation method, and the rockbolt is detected by ultrasonic guided waves to study the propagation law of ultrasonic guided waves in defective rockbolt systems and the bond quality of rockbolts under the combined action of pull-out load and confining pressure. The numerical simulation results show that the length and location of bond defects can be detected by ultrasonic guided waves under the combined action of pull-out load and confining pressure. Under no pull-out load, with increasing confining pressure, the low-frequency part of the guided wave frequency in the rockbolt increases, the high-frequency part decreases, the weakening effect of the confining pressure on the guided wave propagation law increases, and the bond quality of the rockbolt increases. The existence of defects cannot change the strengthening effect of the confining pressure on the guided wave propagation law under the same pull-out load or the weakening effect of the pull-out load on the guided wave propagation law under the same confining pressure. 展开更多
关键词 Grouted Rockbolt Systems Bond Defect Pull-Out Load Confining Pressure Ultrasonic guided Wave
下载PDF
Endoscopic ultrasound-guided fine-needle aspiration pancreatic adenocarcinoma samples yield adequate DNA for next-generation sequencing:A cohort analysis
18
作者 Stefania Bunduc Bianca Varzaru +10 位作者 Razvan Andrei Iacob Andrei Sorop Ioana Manea Andreea Spiridon Raluca Chelaru Adina Emilia Croitoru Gabriel Becheanu Mona Dumbrava Simona Dima Irinel Popescu Cristian Gheorghe 《World Journal of Gastroenterology》 SCIE CAS 2023年第18期2864-2874,共11页
BACKGROUND Genetic tests are increasingly performed for the management of unresectable pancreatic cancer.For genotyping aimed samples current guidelines recommend using core specimens,although based on moderate qualit... BACKGROUND Genetic tests are increasingly performed for the management of unresectable pancreatic cancer.For genotyping aimed samples current guidelines recommend using core specimens,although based on moderate quality evidence.However,in clinical practice among the endoscopic ultrasound(EUS) guided tissue acquisition methods,fine needle aspiration(FNA) is the most widely performed.AIM To assess the adequacy for next generation sequencing(NGS) of the DNA yielded from EUS-FNA pancreatic adenocarcinoma(PDAC) samples.METHODS Between November 2018 and December 2021,105 patients with PDAC confirmed by EUS-FNA were included in the study at our tertiary gastroenterology center.Either 22 gauge(G) or 19G FNA needles were used.One pass was dedicated to DNA extraction.DNA concentration and purity(A260/280,A260/230) were assessed by spectrophotometry.We assessed the differences in DNA parameters according to needle size and tumor characteristics(size,location) and the adequacy of the extracted DNA for NGS(defined as A260/280 ≥ 1.7,and DNA yield:≥ 10 ng for amplicon based NGS,≥ 50 ng for whole exome sequencing [WES],≥ 100 ng for whole genome sequencing [WGS]) by analysis of variance and ttest respectively.Moreover,we compared DNA purity parameters across the different DNA yield categories.RESULTS Our cohort included 49% male patients,aged 67.02 ± 8.38 years.The 22G needle was used in 71%of the cases.The DNA parameters across our samples varied as follows:DNA yield:1289 ng(inter quartile range:534.75-3101),A260/280 = 1.85(1.79-1.86),A260/230 = 2.2(1.72-2.36).DNA yield was > 10 ng in all samples and > 100 ng in 93% of them(one sample < 50 ng).There were no significant differences in the concentration and A260/280 between samples by needle size.Needle size was the only independent predictor of A260/230 which was higher in the 22G samples(P =0.038).NGS adequacy rate was 90% for 19G samples regardless of NGS type,and for 22G samples it reached 89% for WGS adequacy and 91% for WES and amplicon based NGS.Samples with DNA yield > 100 ng had significantly higher A260/280(1.89 ± 0.32 vs 1.34 ± 0.42,P = 0.013).Tumor characteristics were not corelated with the DNA parameters.CONCLUSION EUS-FNA PDAC samples yield DNA adequate for subsequent NGS.DNA amount was similar between 22G and 19G FNA needles.DNA purity parameters may vary indirectly with needle size. 展开更多
关键词 Pancreatic adenocarcinoma Endoscopic ultrasound guided fine needle aspiration Next generation sequencing DNA yield Needle size Genetic testing
下载PDF
Comparison of trans-gastric vs trans-enteric(trans-duodenal or trans-jejunal)endoscopic ultrasound guided gallbladder drainage using lumen apposing metal stents
19
作者 Dheera Grover Ifrah Fatima Murali Dharan 《World Journal of Gastrointestinal Endoscopy》 2023年第9期574-583,共10页
BACKGROUND Endoscopic ultrasound guided gallbladder drainage(EUS-GBD)is being increasingly used in practice(either as a bridge to cholecystectomy in high-risk patients or as destination therapy in non-surgical patient... BACKGROUND Endoscopic ultrasound guided gallbladder drainage(EUS-GBD)is being increasingly used in practice(either as a bridge to cholecystectomy in high-risk patients or as destination therapy in non-surgical patients).Stents are used to create a conduit between the lumen of the gallbladder(GB)and the intestinal lumen through the gastric or enteric routes.Among the various types of stents used,cautery-enhanced lumen apposing metallic stents(LAMS)may be associated with fewer adverse events(AEs).AIM To compare the clinical success,technical success,and rate of AEs between transgastric(TG)and trans-enteric[transduodenal(TD)/transjejunal(TJ)]approach to GB drainage.Further,we analyzed whether using cautery enhanced stents during EUS-GBD impacts the above parameters.METHODS Study was registered in PROSPERO(CRD42022319019)and comprehensive literature review was conducted.Manuscripts were reviewed for the data collection:Rate of AEs,clinical success,and technical success.Random effects model was utilized for the analysis.RESULTS No statistically significant difference in clinical and technical success between the TD/TJ and TG approaches(P>0.05)were noted.There was no statistically significant difference in the rate of AEs when comparing two-arm studies only.However,when all studies were included in the analysis difference was almost significant favoring the TD/TJ approach.When comparing cautery-enhanced LAMS with non-cautery enhanced LAMS,a statistically significant difference in the rate of AEs was observed when all the studies were included,with the rate being higher in non-cautery enhanced stents(14.0%vs 37.8%;P<0.01).CONCLUSION As per our study results,TD/TJ approach appears to be associated with lower rate of adverse events and comparable efficacy when compared to the TG approach for the EUS-GBD.Additionally,use of cautery-enhanced LAMS for EUS-GBD is associated with a more favorable adverse event profile compared to cold LAMS.Though the approach chosen depends on several patient and physician factors,the above findings could help in deciding the ideal drainage route when both TG and TD/TJ approaches are feasible. 展开更多
关键词 Transduodenal TRANSGASTRIC CAUTERY Endoscopic ultrasound guided gallbladder drainage AXIOS
下载PDF
Imaged guided surgery during arteriovenous malformation of gastrointestinal stromal tumor using hyperspectral and indocyanine green visualization techniques:A case report
20
作者 Tristan Wagner Onur Mustafov +6 位作者 Marielle Hummels Anders Grabenkamp Michael N Thomas Lars Mortimer Schiffmann Christiane J Bruns Dirk L Stippel Roger Wahba 《World Journal of Clinical Cases》 SCIE 2023年第23期5530-5537,共8页
BACKGROUND This case report demonstrates the simultaneous development of a gastrointestinal stromal tumour(GIST)with arteriovenous malformations(AVMs)within the jejunal mesentery.A 74-year-old male presented to the de... BACKGROUND This case report demonstrates the simultaneous development of a gastrointestinal stromal tumour(GIST)with arteriovenous malformations(AVMs)within the jejunal mesentery.A 74-year-old male presented to the department of surgery at our institution with a one-month history of abdominal pain.Contrast-enhanced computed tomography revealed an AVM.During exploratory laparotomy,hyperspectral imaging(HSI)and indocyanine green(ICG)fluorescence were used to evaluate the extent of the tumour and determine the resection margins.Intraoperative imaging confirmed AVM,while histopathological evaluation showed an epithelioid,partially spindle cell GIST.CASE SUMMARY This is the first case reporting the use of HSI and ICG to image GIST intermingled with an AVM.The resection margins were planned using intraoperative analysis of additional optical data.Image-guided surgery enhances the clinician’s knowledge of tissue composition and facilitates tissue differentiation.CONCLUSION Since image-guided surgery is safe,this procedure should increase in popularity among the next generation of surgeons as it is associated with better postoperative outcomes. 展开更多
关键词 Imaged guided surgery Hyperspecteral imaging Gastrointestinal stromal tumour Arteriovenous malformation Case report
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部