Detection of internal crack growth in polyethylene pipe using guided wave ultrasonic testing

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.

Comparison of Transrectal Prostate Digital and Ultrasound-Guided Core Biopsies in 400 Men in a Low-and-Middle Income Country

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.

Application of Automated Guided Vehicles in Smart Automated Warehouse Systems:A Survey

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.

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

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。

Endoscopic ultrasound-guided fine-needle aspiration pancreatic adenocarcinoma samples yield adequate DNA for next-generation sequencing:A cohort analysis

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.

Guided Dropout: Improving Deep Networks Without Increased Computation

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.

A greedy path planning algorithm based on pre-path-planning and real-time-conflict for multiple automated guided vehicles in large-scale outdoor scenarios

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.

Endoscopic ultrasound guided biliary drainage in surgically altered anatomy: A comprehensive review of various approaches

Endoscopic retrograde cholangiopancreatography(ERCP)is the preferred modality for drainage of the obstructed biliary tree.In patients with surgically altered anatomy,ERCP using standard techniques may not be feasible.Enteroscope assisted ERCP is usually employed with variable success rate.With advent of endoscopic ultrasound(EUS),biliary drainage procedures in patients with biliary obstruction and surgically altered anatomy is safe and effective.In this narrative review,we discuss role of EUS guided biliary drainage in patients with altered anatomy and the various approaches used in patients with benign and malignant biliary obstruction.

Imaged guided surgery during arteriovenous malformation of gastrointestinal stromal tumor using hyperspectral and indocyanine green visualization techniques:A case report

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.

Comparison of trans-gastric vs trans-enteric(trans-duodenal or trans-jejunal)endoscopic ultrasound guided gallbladder drainage using lumen apposing metal stents

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.

Endoscopic ultrasound guided gastroenterostomy:Technical details updates,clinical outcomes,and adverse events

Endoscopic ultrasound-guided gastroenterostomy(EUS-GE)has been transformed from an innovative technique,into a viable alternative to enteral stenting and surgical gastrointestinal anastomosis for patients with gastric outlet obstruction.Even EUS-GE guided ERCP and EUS-guided gastrointestinal anastomosis for the treatment of afferent loop syndrome have been performed,giving patients more less invasive options.However,EUS-GE is still a technically challenging procedure.In order to improve EUS-GE,several techniques have been reported to improve the technical details.With EUS-GE widely performed,more data about EUS-GE’s clinical outcomes have been reported.The aim of the current review is to describe technical details updates,clinical outcomes,and adverse events of EUS-GE.

Propagation Characteristics of Ultrasonic Guided Waves in Grouted Rockbolt Systems with Bond Defects under Different Confining Conditions

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.

The Inspection of Level Crossing Rails Using Guided Waves

Level crossing rails are high risk areas due to the combination of the limited effectiveness of current inspection methods and high corrosion rates which often exist.This paper discusses the current UK standard practices for the periodic inspection of level crossing rails using visual(VT)and conventional ultrasonic(UT)methods.The limitations of these methods are discussed and how these limitations affect the overall maintenance program for level crossings.A new inspection method,guided wave testing(GWT)is then described with particular emphasis on its advantages for inspecting level crossings.Finally,a review is given of the current Network Rail trial of GWT on level crossings using the G-Scan system,with representative results which demonstrate the effectiveness of GWT for this application.

A Small Target Detection Method for Sea Surface Based on Guided Filtering and Local Mean Gray Difference

The traditional small target detection algorithm often results in a high false alarm rate on the sea surface background. To address this issue, a small target detection method based on guided filtering and local average gray level difference was proposed in this paper for the sea surface. Firstly, the method enhanced the details of the small targets by employing guided filtering to suppress the background clutter and noise in the sea surface image. Subsequently, the local average gray level difference of each point in the image was calculated to further distinguish the targets from other interference points. Finally, the threshold segmentation method was utilized to obtain the actual small targets on the sea surface. After conducting experiments on various sea surface scenes, the LSCRG, BSF, and ROC curve were computed for the proposed method and five other algorithms. Comparative analysis with BS, Top-hat, TDLMS, Max-median, and LCM demonstrates the superiority of the proposed method for infrared small target detection on the sea surface.

Guided Care在老年慢性病管理中的效果研究

目的研究老年慢性病患者实施Guided Care的管理效果。方法应用生活质量量表对120例老年慢性病患者进行实施前后效果观察评价,其中研究组60例,实施Guided Care,对照组60例,定期门诊随访,以分析两组老年慢性病患者生活质量、血糖达标情况。结果两组老年慢性病患者在实施前后生活质量、血糖达标情况效果有显著性差异(P<0.01)。结论实施Guided Care为老年慢性病患者提供科学的综合服务,为临床提供更具体有效适合中国实际新的管理模式,值得临床推广应用。

肠造口病人实施Guided Care护理模式对生活质量的影响

[目的]研究肠造口病人实施Guided Care护理模式对生活质量的影响。[方法]选择80例肠造口病人,随机分为试验组和对照组,试验组实施Guided Care护理模式,对照组实施常规护理模式。干预后6个月比较两组病人并发症的发生情况,并应用简明生存质量量表(SF-36)评定实施前后两组病人的生活质量。[结果]两组病人在实施护理干预后并发症的发生情况、生活质量差异均有统计学意义(P<0.05或P<0.01)。[结论]对肠造口病人实施Guided Care护理模式,可以减少肠造口病人的并发症,提高肠造口病人生活质量。

Endoscopic ultrasonography guided biliary drainage: Summary of consortium meeting, May 7^(th) , 2011, Chicago

Endoscopic retrograde cholangiopancreatography (ERCP) has become the preferred procedure for biliary or pancreatic drainage in various pancreatico-biliary disorders. With a success rate of more than 90%, ERCP may not achieve biliary or pancreatic drainage in cases with altered anatomy or with tumors obstructing access to the duodenum. In the past those failures were typically managed exclusively by percutaneous approaches by interventional radiologists or surgical intervention. The morbidity associated was significant especially in those patients with advanced malignancy, seeking minimally invasive interventions and improved quality of life. With the advent of biliary drainage via endoscopic ultrasound (EUS) guidance, EUS guided biliary drainage has been used more frequently within the last decade in different countries. As with any novel advanced endoscopic procedure that encompasses various approaches, advanced endoscopists all over the world have innovated and adopted diverse EUS guided biliary and pancreatic drainage techniques. This diversity has resulted in variations and improvements in EUS Guided biliary and pancreatic drainage; and over the years has led to an extensive nomenclature. The diversity of techniques, nomenclature and recent progress in our intrumentation has led to a dedicated meeting on May 7 th , 2011 during Digestive Disease Week 2011. More than 40 advanced endoscopists from United States, Brazil, Mexico, Venezuela, Colombia, Italy, France, Austria, Germany, Spain, Japan, China, South Korea and India attended this pivotal meeting. The meeting covered improved EUS guided biliary access and drainage procedures, terminology, nomenclature, training and credentialing; as well as emerging devices for EUS guided biliary drainage. This paper summarizes the meeting's agenda and the conclusions generated by the creation of this consortium group.

基于Guided Filter的地形图中线要素提取算法

针对彩色扫描地形图中线要素与背景要素难以分离,现有线要素提取算法提取的结果中存在边界不准确的问题,提出基于Guided Filter的地形图中线要素提取算法。利用基于能量密度和Shear变换相结合的线要素提取算法对线要素进行粗提取;引入Guided Filter,以源地形图图像作为Guided Filter的引导图像,以粗提取的线要素图像作为Guided Filter的输入图像,经过滤波处理获得的线要素信息更为显著;利用OTSU算法得到最终的线要素信息。实验结果表明:相对于现有的线要素提取算法,提出的算法能够更为准确地提取出地形图中的线要素,并具有更好的噪声抑制能力。

Research on Search Laws of Image Guided Missile

When image guided missile adopts guided search and common search law to search ground targets, under some conditions the movement of image on the monitor screen will be dissymmetrical, which is harmful for shooter to acquire and capture targets. To remove the dissymmetry of the image movement, such common search laws as parallel search law, ＂X＂ style search law, search law of one-dimension visual effect and cone search law are improved and designed again. Simulation results show that the dissymmetry can be removed by adopting all the above four improved search laws, but the search track of improved cone search law has serious transmutation compared with the original search track. The other three improved search laws have little transmutation of the search track, and they all can keep the main characters of the original search law. Study resuits are helpful for image guided missile in adopting guided search to choose appropriate search law.

基于QoS Guided Min-min任务调度算法局部优化

在对网格环境中现有任务调度算法的研究基础上,分析了调度算法中经典的Min-Min算法和Qos GuidedMin-min算法,指出了这些算法中所存在的负载不平衡的缺点,在此基础上,提出对Qos Guided Min-min算法进行局部优化和改进,并采用SimGrid模拟器对优化的算法进行仿真,结果表明,优化改进后的算法合理,具有较高的性能。