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Overlapping approach Proton Pump Inhibitors/Nux vomica-Heel as new intervention for gastro-esophageal reflux management:Delphi consensus study
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作者 Edda Battaglia Luciano Bertolusso +2 位作者 Marco Del Prete Marco Monzani Marco Astegiano 《World Journal of Gastroenterology》 SCIE CAS 2024年第18期2467-2478,共12页
BACKGROUND Gastro-esophageal reflux disease(GERD)may affect the upper digestive tract;up to 20%of population in Western nations are affected by GERD.Antacids,histamine H2-receptor antagonists,and Proton Pump Inhibitor... BACKGROUND Gastro-esophageal reflux disease(GERD)may affect the upper digestive tract;up to 20%of population in Western nations are affected by GERD.Antacids,histamine H2-receptor antagonists,and Proton Pump Inhibitors(PPIs)are considered the referring medications for GERD.Nevertheless,PPIs must be managed carefully because their use,especially chronic,could be linked with some adverse effects.An effective and safe alternative pharmacological tool for GERD is needed.After the identification of potentially new medications to flank PPIs,it is mandatory to revise and improve good clinical practices even through a consensus process.AIM To optimize diagnosis and treatment guidelines for GERD through a consensus based on Delphi method.METHODS The availability of clinical studies describing the action of the multicomponent/multitarget medication Nux vomica-Heel,subject of the consensus,is the basic prerequisite for the consensus itself.A modified Delphi process was used to reach a consensus among a panel of Italian GERD specialists on the overlapping approach PPIs/Nux vomica-Heel as a new intervention model for the management of GERD.The Voting Consensus group was composed of 49 Italian Medical Doctors with different specializations:Gastroenterology,otolaryngology,geriatrics,and general medicine.A scientific committee analyzed the literature,determined areas that required investigation(in agreement with the multiple-choice questionnaire results),and identified two topics of interest:(1)GERD disease;and(2)GERD treatment.Statements for each of these topics were then formulated and validated.The Delphi process involved two rounds of questioning submitted to the panel experts using an online platform.RESULTS According to their routinary GERD practice and current clinical evidence,the panel members provided feedback to each questionnaire statement.The experts evaluated 15 statements and reached consensus on all 15.The statements regarding the GERD disease showed high levels of agreement,with consensus ranging from 70%to 92%.The statements regarding the GERD treatment also showed very high levels of agreement,with consensus ranging from 90%to 100%.This Delphi process was able to reach consensus among physicians in relevant aspects of GERD management,such as the adoption of a new approach to treat patients with GERD based on the overlapping between PPIs and Nux vomica-Heel.The consensus was unanimous among the physicians with different specializations,underlying the uniqueness of the agreement reached to identify in the overlapping approach between PPIs and Nux vomica-Heel a new intervention model for GERD management.The results support that an effective approach to deprescribe PPIs through a progressive decalage timetable(reducing PPIs administration to as-needed use),should be considered.CONCLUSION Nux vomica-Heel appears to be a valid opportunity for GERD treatment to favor the deprescription of PPIs and to maintain low disease activity together with the symptomatology remission. 展开更多
关键词 Gastro-esophageal reflux disease Proton Pump Inhibitors CONSENSUS Nux vomica-Heel overlapping Decalage
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Large-Scale Multi-Objective Optimization Algorithm Based on Weighted Overlapping Grouping of Decision Variables
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作者 Liang Chen Jingbo Zhang +2 位作者 Linjie Wu Xingjuan Cai Yubin Xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期363-383,共21页
The large-scale multi-objective optimization algorithm(LSMOA),based on the grouping of decision variables,is an advanced method for handling high-dimensional decision variables.However,in practical problems,the intera... The large-scale multi-objective optimization algorithm(LSMOA),based on the grouping of decision variables,is an advanced method for handling high-dimensional decision variables.However,in practical problems,the interaction among decision variables is intricate,leading to large group sizes and suboptimal optimization effects;hence a large-scale multi-objective optimization algorithm based on weighted overlapping grouping of decision variables(MOEAWOD)is proposed in this paper.Initially,the decision variables are perturbed and categorized into convergence and diversity variables;subsequently,the convergence variables are subdivided into groups based on the interactions among different decision variables.If the size of a group surpasses the set threshold,that group undergoes a process of weighting and overlapping grouping.Specifically,the interaction strength is evaluated based on the interaction frequency and number of objectives among various decision variables.The decision variable with the highest interaction in the group is identified and disregarded,and the remaining variables are then reclassified into subgroups.Finally,the decision variable with the strongest interaction is added to each subgroup.MOEAWOD minimizes the interactivity between different groups and maximizes the interactivity of decision variables within groups,which contributed to the optimized direction of convergence and diversity exploration with different groups.MOEAWOD was subjected to testing on 18 benchmark large-scale optimization problems,and the experimental results demonstrate the effectiveness of our methods.Compared with the other algorithms,our method is still at an advantage. 展开更多
关键词 Decision variable grouping large-scale multi-objective optimization algorithms weighted overlapping grouping direction-guided evolution
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Overlapping infections of Mycobacterium canariasense and Nocardia farcinica in an immunocompetent patient:A case report
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作者 Hai-Yan Huang Kun-Peng Bu +1 位作者 Jin-Wei Liu Jing Wei 《World Journal of Clinical Cases》 SCIE 2024年第12期2079-2085,共7页
BACKGROUND Infections by non-tuberculous mycobacteria(NTM)have become more common in recent years.Mycobacterium canariasense(M.canariasense)was first reported as an opportunistic pathogen in 2004,but there have been v... BACKGROUND Infections by non-tuberculous mycobacteria(NTM)have become more common in recent years.Mycobacterium canariasense(M.canariasense)was first reported as an opportunistic pathogen in 2004,but there have been very few case reports since then.Nocardia is a genus of aerobic and Gram-positive bacilli,and these species are also opportunistic pathogens and in the Mycobacteriales order.Conventional methods for diagnosis of NTM are inefficient.Metagenomic next-generation sequencing(mNGS)can rapidly detect many pathogenic microorganisms,even rare species.Most NTM and Nocardia infections occur in immunocompromised patients with atypical clinical symptoms.There are no previous reports of infection by M.canariasense and Nocardia farcinica(N.farcinica),especially in immunocompetent patients.This case report describes an immunocompetent 52-year-old woman who had overlapping infections of M.canariasense,N.farcinica,and Candida parapsilosis(C.parapsilosis)based on mNGS.CASE SUMMARY A 52-year-old woman presented with a productive cough and chest pain for 2 wk,and recurrent episodes of moderate-grade fever for 1 wk.She received antibiotics for 1 wk at a local hospital,and experienced defervescence,but the productive cough and chest pain persisted.We collected samples of a lung lesion and alveolar lavage fluid for mNGS.The lung tissue was positive for M.canariasense,N.farcinica,and C.parapsilosis,and the alveolar lavage fluid was positive for M.canariasense.The diagnosis was pneumonia,and application of appropriate antibiotic therapy cured the patient.CONCLUSION Etiological diagnosis is critical for patients with infectious diseases.mNGS can identify rare and novel pathogens,and does not require a priori knowledge. 展开更多
关键词 overlapping infection Mycobacterium canariasense Nocardia farcinica Metagenomic next-generation sequencing technology Case report
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Organized macro-scale membrane size reduction in vanadium redox flow batteries:Part 1.General concept 被引量:1
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作者 Abdulmonem Fetyan Bronston P.Benetho Musbaudeen O.Bamgbopa 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期64-70,I0003,共8页
The high costs of the currently used membranes in vanadium redox flow batteries(VRFBs)contribute to the price of the vanadium redox flow battery systems and therefore limit the market share of the VRFBs.Here we report... The high costs of the currently used membranes in vanadium redox flow batteries(VRFBs)contribute to the price of the vanadium redox flow battery systems and therefore limit the market share of the VRFBs.Here we report a detailed simulation and experimental studies on the effect of membrane reduction of single-cell VRFB.Different simulated designs demonstrate that a proposed centred and double-strip membrane coverage showed a promising performance.Experimental charge-discharge profile of different membrane size reduction,which showed good agreement with simulated data,suggests that the membrane size can comfortably be reduced by up to 20%without severe efficiency or discharge capacity loss.Long-term cycling of 80%centred membrane coverage showed improved capacity retention during the latter cycles with almost 1%difference in capacity and only 2%in energy efficiency when compared to the fully covered-membrane cell.The results hold great promise for the development of cheap RFB stacks and facilitate the way to develop new cell designs with non-overlapping electrodes geometry.Therefore,giving more flexibility to improve the overall performance of the system. 展开更多
关键词 Membrane reduction Electrodes overlapping Cell-Architecture Multiphysics simulation Redox Flow Batteries
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Set pair three-way overlapping community discovery algorithm for weighted social internet of things 被引量:1
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作者 Chunying Zhang Jing Ren +3 位作者 Lu Liu Shouyue Liu Xiaoqi Li Liya Wang 《Digital Communications and Networks》 SCIE CSCD 2023年第1期3-13,共11页
There are many problems in Social Internet of Things(IoTs),such as complex topology information,different degree of association between nodes and overlapping communities.The idea of set pair information grain computin... There are many problems in Social Internet of Things(IoTs),such as complex topology information,different degree of association between nodes and overlapping communities.The idea of set pair information grain computing and clustering is introduced to solve the above problems so as to accurately describe the similarity between nodes and fully explore the multi-community structure.A Set Pair Three-Way Overlapping Community Discovery Algorithm for Weighted Social Internet of Things(WSIoT-SPTOCD)is proposed.In the local network structure,which fully considers the topological information between nodes,the set pair connection degree is used to analyze the identity,difference and reverse of neighbor nodes.The similarity degree of different neighbor nodes is defined from network edge weight and node degree,and the similarity measurement method of set pair between nodes based on the local information structure is proposed.According to the number of nodes'neighbors and the connection degree of adjacent edges,the clustering intensity of nodes is defined,and an improved algorithm for initial value selection of k-means is proposed.The nodes are allocated according to the set pair similarity between nodes and different communities.Three-way community structures composed of a positive domain,boundary domain and negative domain are generated iteratively.Next,the overlapping node set is generated according to the calculation results of community node membership.Finally,experiments are carried out on artificial networks and real networks.The results show that WSIoT-SPTOCD performs well in terms of standardized mutual information,overlapping community modularity and F1. 展开更多
关键词 Social internet of things Set pair analysis K-MEANS Local information structure overlapping community
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An Imbalanced Dataset and Class Overlapping Classification Model for Big Data 被引量:1
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作者 Mini Prince P.M.Joe Prathap 《Computer Systems Science & Engineering》 SCIE EI 2023年第2期1009-1024,共16页
Most modern technologies,such as social media,smart cities,and the internet of things(IoT),rely on big data.When big data is used in the real-world applications,two data challenges such as class overlap and class imba... Most modern technologies,such as social media,smart cities,and the internet of things(IoT),rely on big data.When big data is used in the real-world applications,two data challenges such as class overlap and class imbalance arises.When dealing with large datasets,most traditional classifiers are stuck in the local optimum problem.As a result,it’s necessary to look into new methods for dealing with large data collections.Several solutions have been proposed for overcoming this issue.The rapid growth of the available data threatens to limit the usefulness of many traditional methods.Methods such as oversampling and undersampling have shown great promises in addressing the issues of class imbalance.Among all of these techniques,Synthetic Minority Oversampling TechniquE(SMOTE)has produced the best results by generating synthetic samples for the minority class in creating a balanced dataset.The issue is that their practical applicability is restricted to problems involving tens of thousands or lower instances of each.In this paper,we have proposed a parallel mode method using SMOTE and MapReduce strategy,this distributes the operation of the algorithm among a group of computational nodes for addressing the aforementioned problem.Our proposed solution has been divided into three stages.Thefirst stage involves the process of splitting the data into different blocks using a mapping function,followed by a pre-processing step for each mapping block that employs a hybrid SMOTE algo-rithm for solving the class imbalanced problem.On each map block,a decision tree model would be constructed.Finally,the decision tree blocks would be com-bined for creating a classification model.We have used numerous datasets with up to 4 million instances in our experiments for testing the proposed scheme’s cap-abilities.As a result,the Hybrid SMOTE appears to have good scalability within the framework proposed,and it also cuts down the processing time. 展开更多
关键词 Imbalanced dataset class overlapping SMOTE MAPREDUCE parallel programming OVERSAMPLING
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Partially Overlapping Channel Assignment Using Bonded and Non-Bonded Channels in IEEE 802.11n WLAN
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作者 MdSelim Al Mamun Fatema Akhter 《Computers, Materials & Continua》 SCIE EI 2022年第5期3161-3178,共18页
Nowadays,wireless local area network(WLAN)has become prevalent Internet access due to its low-cost gadgets,flexible coverage and hasslefree simple wireless installation.WLAN facilitates wireless Internet services to u... Nowadays,wireless local area network(WLAN)has become prevalent Internet access due to its low-cost gadgets,flexible coverage and hasslefree simple wireless installation.WLAN facilitates wireless Internet services to users with mobile devices like smart phones,tablets,and laptops through deployment of multiple access points(APs)in a network field.Every AP operates on a frequency band called channel.Popular wireless standard such as IEEE 802.11n has a limited number of channels where frequency spectrum of adjacent channels overlaps partially with each other.In a crowded environment,users may experience poor Internet services due to channel collision i.e.,interference from surrounding APs that affects the performance of the WLAN system.Therefore,it becomes a challenge to maintain expected performance in a crowded environment.A mathematical model of throughput considering interferences from surrounding APs can play an important role to set up a WLAN system properly.While set up,assignment of channels considering interference can maximize network performance.In this paper,we investigate the signal propagation of APs under interference of partially overlapping channels for both bonded and non-bonded channels.Then,a throughput estimation model is proposed using difference of operating channels and received signal strength indicator(RSSI).Then,a channel assignment algorithm is introduced using proposed throughput estimation model.Finally,the efficiency of the proposal is verified by numerical experiments using simulator.The results show that the proposal selects the best channel combination of bonded and non-bonded channels that maximize the performance. 展开更多
关键词 Wireless local area network partially overlapping channel throughput estimation model channel assignment algorithm
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Computation of Optical Force on Nanoparticles Using Locally Non-Orthogonal Overlapping Yee FDTD Method
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作者 Jinjie Liu Moysey Brio Jerome V. Moloney 《Journal of Electromagnetic Analysis and Applications》 2012年第11期452-456,共5页
In this paper, a locally non-orthogonal overlapping Yee (OY) FDTD method is proposed in order to accurately calculates the optical force on dielectric and dispersive nanoparticles. It extends our previous work to geom... In this paper, a locally non-orthogonal overlapping Yee (OY) FDTD method is proposed in order to accurately calculates the optical force on dielectric and dispersive nanoparticles. It extends our previous work to geometries with sharp corners and dispersive materials. In addition to consistently achieving the smallest errors in comparison to the standard FDTD method, the OY approach is a stable non-orthogonal FDTD method that attains second-order convergence when sharp corners are present. 展开更多
关键词 FDTD overlapping Yee Optical FORCE NANOpartICLE
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Autoimmune hepatitis-primary biliary cholangitis overlap syndrome complicated by various autoimmune diseases:A case report
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作者 Yu-Jie Qin Ting Gao +2 位作者 Xing-Nian Zhou Ming-Liang Cheng Hong Li 《World Journal of Clinical Cases》 SCIE 2024年第6期1174-1181,共8页
BACKGROUND Autoimmune hepatitis(AIH)and primary biliary cholangitis(PBC)are two common clinical autoimmune liver diseases,and some patients have both diseases;this feature is called AIH-PBC overlap syndrome.Autoimmune... BACKGROUND Autoimmune hepatitis(AIH)and primary biliary cholangitis(PBC)are two common clinical autoimmune liver diseases,and some patients have both diseases;this feature is called AIH-PBC overlap syndrome.Autoimmune thyroid disease(AITD)is the most frequently overlapping extrahepatic autoimmune disease.Immunoglobulin(IgG)4-related disease is an autoimmune disease recognized in recent years,characterized by elevated serum IgG4 levels and infiltration of IgG4-positive plasma cells in tissues.CASE SUMMARY A 68-year-old female patient was admitted with a history of right upper quadrant pain,anorexia,and jaundice on physical examination.Laboratory examination revealed elevated liver enzymes,multiple positive autoantibodies associated with liver and thyroid disease,and imaging and biopsy suggestive of pancreatitis,hepatitis,and PBC.A diagnosis was made of a rare and complex overlap syndrome of AIH,PBC,AITD,and IgG4-related disease.Laboratory features improved on treatment with ursodeoxycholic acid,methylprednisolone,and azathioprine.CONCLUSION This case highlights the importance of screening patients with autoimmune diseases for related conditions. 展开更多
关键词 Overlap syndrome Autoimmune hepatitis Primary biliary cholangitis Primary sclerosing cholangitis Autoimmune thyroid disease Case report
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空肠后离断Overlap吻合法在腹腔镜根治性全胃切除术中的应用
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作者 徐李嘉 沈晓军 《腹部外科》 2024年第2期106-110,共5页
目的探讨空肠后离断Overlap吻合法相比传统Overlap吻合法在腹腔镜根治性全胃切除术中的优势及安全性。方法回顾分析2018年3月至2023年6月在昆山市第一人民医院行腹腔镜根治性全胃切除术的胃癌病人资料共43例,根据食管空肠吻合方式的不... 目的探讨空肠后离断Overlap吻合法相比传统Overlap吻合法在腹腔镜根治性全胃切除术中的优势及安全性。方法回顾分析2018年3月至2023年6月在昆山市第一人民医院行腹腔镜根治性全胃切除术的胃癌病人资料共43例,根据食管空肠吻合方式的不同进行分组。研究组25例,采用空肠后离断Overlap吻合法进行食管空肠重建;对照组18例,采用传统Overlap吻合法。比较两组病人在围手术期及术后近期指标等方面有无差异。结果两组病人的一般资料比较,差异均无统计学意义(均P>0.05)。两组病人均顺利完成手术,无中转开腹病例。在饮食随访中,研究组病人术后1个月均已恢复半流质饮食或普食,术后3个月均能进食普食。两组病人的术中出血量、术后住院时间以及吻合口漏、吻合口狭窄、吻合口出血等吻合口并发症的发生率相比较,差异均无统计学意义(均P>0.05)。同对照组相比较,研究组的食管空肠吻合时间[(25.4±4.3)min比(39.8±4.5)min,t=–10.549,P<0.001]和手术时间[237 min(230~250 min)比258.6 min(250~285 min),Z=–5.517,P<0.001]均缩短,差异具有统计学意义(均P<0.001)。结论在腹腔镜根治性全胃切除的病人中,改良后的空肠后离断Overlap吻合较传统Overlap吻合更加简便,是一种较好的、安全可行的吻合方式。 展开更多
关键词 全腹腔镜全胃切除术 胃癌 Overlap吻合
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Real-Time Mosaic Method of Aerial Video Based on Two-Stage Key Frame Selection Method
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作者 Minwen Yuan Yonghong Long Xin Li 《Open Journal of Applied Sciences》 2024年第4期1008-1021,共14页
A two-stage automatic key frame selection method is proposed to enhance stitching speed and quality for UAV aerial videos. In the first stage, to reduce redundancy, the overlapping rate of the UAV aerial video sequenc... A two-stage automatic key frame selection method is proposed to enhance stitching speed and quality for UAV aerial videos. In the first stage, to reduce redundancy, the overlapping rate of the UAV aerial video sequence within the sampling period is calculated. Lagrange interpolation is used to fit the overlapping rate curve of the sequence. An empirical threshold for the overlapping rate is then applied to filter candidate key frames from the sequence. In the second stage, the principle of minimizing remapping spots is used to dynamically adjust and determine the final key frame close to the candidate key frames. Comparative experiments show that the proposed method significantly improves stitching speed and accuracy by more than 40%. 展开更多
关键词 UAV Aerial Video Image Stiching Key Frame Selection overlapping Rate Remap Error
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Biomathematical study of time-dependent flow of a Carreau nanofluid through inclined catheterized arteries with overlapping stenosis 被引量:6
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作者 Ashfaq Ahmed Sohail Nadeem 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第11期2725-2744,共20页
This work is concerned with the analysis of blood flow through inclined catheterized arteries having a balloon(angioplasty) with time-variant overlapping stenosis. The nature of blood in small arteries is analyzed mat... This work is concerned with the analysis of blood flow through inclined catheterized arteries having a balloon(angioplasty) with time-variant overlapping stenosis. The nature of blood in small arteries is analyzed mathematically by considering it as a Carreau nanofluid. The highly nonlinear momentum equations of nanofluid model are simplified by considering the mild stenosis case. The formulated problem is solved by a homotopy perturbation expansion in terms of a variant of the Weissenberg number to obtain explicit forms for the axial velocity, the stream function, the pressure gradient, the resistance impedance and the wall shear stress distribution. These solutions depend on the Brownian motion number, thermophoresis number, local temperature Grashof number G_r and local nanoparticle Grash of number B_r. The results were also studied for various values of the physical parameters, such as the Weissenberg number W_i, the power law index n, the taper angle φ, the maximum height of stenosis δ~*, the angle of inclination α, the maximum height of balloon σ~*, the axial displacement of the balloon z_d~*,the flow rate F and the Froud number Fr. The obtained results show that the transmission of axial velocity curves through a Newtonian fluid(Wi=0, n=1, Gr=0, Br=0, Nt=0, Nb≠0) is substantially lower than that through a Carreau nanofluid near the wall of balloon while the inverse occurs in the region between the balloon and stenosis. The streamlines have a clearly distinguished shifting toward the stenotic region and this shifting appears near the wall of the balloon, while it has almost disappeared near the stenotic wall and the trapping bolus in the case of horizontal arteries and Newtonian fluid(Wi=0, n=1, Gr=0, Br=0, Nt=0, Nb≠0) does not appear but for the case of Carreau nanofluid bolus appears. 展开更多
关键词 overlapping stenosed artery NANOFLUID Grashof number BROWNIAN motion THERMOPHORESIS pharmacology
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FEM SIMULATION OF RESIDUAL STRESSES INDUCED BY LASER SHOCK WITH OVERLAPPING LASER SPOTS 被引量:9
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作者 Y.X. Hu Z.Q. Yao 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2008年第2期125-132,共8页
The finite element method is presented to attain the numerical simulation of the residual stresses field in the material treated by laser shock processing. The distribution of residual stresses generated by a single l... The finite element method is presented to attain the numerical simulation of the residual stresses field in the material treated by laser shock processing. The distribution of residual stresses generated by a single laser shock with square and round laser spot is predicted and validated by experimental results. With the Finite Element Method (FEM) model, effects of different overlapping rates and impact sequences on the distribution of residual stresses are simulated. The results indicate that: (1) Overlapping laser shock can increase the compressive residual stresses. However, it is not effective on the growth of plastically affected depth; (2) Overlapping rate should be optimized and selected carefully for the large area treatment. Appropriate overlapping rate is beneficial to obtain a homogeneous residual stress field; (3) The impact sequence has a great effect on the residual stress field. It can greatly attenuate the phenomenon of the “residual stress hole” to obtain a homogeneous residual stress field. 展开更多
关键词 Laser shock processing overlapping Residual stress Finite element method
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Detecting overlapping communities in networks via dominant label propagation 被引量:10
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作者 孙鹤立 黄健斌 +2 位作者 田勇强 宋擒豹 刘怀亮 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期551-559,共9页
Community detection is an important methodology for understanding the intrinsic structure and function of a realworld network. In this paper, we propose an effective and efficient algorithm, called Dominant Label Prop... Community detection is an important methodology for understanding the intrinsic structure and function of a realworld network. In this paper, we propose an effective and efficient algorithm, called Dominant Label Propagation Algorithm(Abbreviated as DLPA), to detect communities in complex networks. The algorithm simulates a special voting process to detect overlapping and non-overlapping community structure in complex networks simultaneously. Our algorithm is very efficient, since its computational complexity is almost linear to the number of edges in the network. Experimental results on both real-world and synthetic networks show that our algorithm also possesses high accuracies on detecting community structure in networks. 展开更多
关键词 overlapping community detection dominant label propagation complex network
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EFFECT OF OVERLAPPING TREATMENT ON MICROSTRUCTURE OF LASER-CLAD WC/Ni60A COMPOSITE COATING 被引量:6
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作者 C.Z. Chen 1,2) , X.D. Liu 3) , S.J. Zhang 4) , D.W. Cui 1) , T.Q. Lei 2) and J.H. Yu 1) 1) College of Material Science and Technology, Shandong University of Technology, Jinan 250061, China 2) College of Material Science and T 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第5期1014-1018,共5页
The effect of overlapping treatment on microstructure of laser clad WC/Ni60A composite coating was studied with XRD, SEM, TEM and SAED etc. The results show that during the overlapping treatment the existence of the ... The effect of overlapping treatment on microstructure of laser clad WC/Ni60A composite coating was studied with XRD, SEM, TEM and SAED etc. The results show that during the overlapping treatment the existence of the residual heat and edge angle effect on the substrate has changed the composition and microstructure of the coating by raising the fusion temperature and increasing the dilution degree of the coating. 展开更多
关键词 laser cladding WC/Ni60A MICROSTRUCTURE overlapping edge angle effect
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Quantitative Analysis and Affecting Factors of the Overlapping Degree of Interfacial Transition Zone between Neighboring Aggregates in Concrete 被引量:5
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作者 孙国文 孙伟 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第1期147-153,共7页
Based on the nearest surface function formula, a quantitative formula to measure the overlapping degree between the interfacial transition zone (ITZ) of neighboring aggregate particles was put forward. The formula w... Based on the nearest surface function formula, a quantitative formula to measure the overlapping degree between the interfacial transition zone (ITZ) of neighboring aggregate particles was put forward. The formula was further deduced to quantitatively analyze the influence of the volume fraction of aggregate, ITZ thickness and the maximum aggregate diameter on the overlapping degree between neighboring ITZ. The volume of ITZ was quantitatively calculated in actual concrete by comparing the nearest surface function formula with an approximate method, that is the surface area of the aggregates multiplied by the uniform thickness of the ITZ layers. The results showed that the influencing order of these three factors on the overlapping degree between neighboring ITZ in turn was the interface thickness, aggregate volume fraction and the maximum aggregate diameter; As long as the interface thickness 50 μm and the aggregate volume fraction 50%, the calculated error between two methods mentioned above is about 10 %. 展开更多
关键词 CONCRETE interfacial transition zone degree of overlapping volume fraction Fuller distribution
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Effect of Interface Friction on Overlapping Sheets Bulging Formability and Microstructure of 5A02 Aluminum Alloy 被引量:3
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作者 高铁军 YAO Yongjie +1 位作者 WANG Xiaokang SHAO Ruowei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第4期919-924,共6页
Aluminum alloy 5 A02 with low plasticity was used as target sheet, and stainless steel SUS304 with good plasticity was used as overlapping sheet to investigate the effect of interface friction on bulging formability a... Aluminum alloy 5 A02 with low plasticity was used as target sheet, and stainless steel SUS304 with good plasticity was used as overlapping sheet to investigate the effect of interface friction on bulging formability and microstructure of target sheet in overlapping sheets bulging process. Sheet sliding experiment was performed to measure interface friction coefficient of 5 A02/SUS304 in different lubricating conditions and normal pressure. Overlapping sheets bulging experiment of 5 A02/SUS304 was carried out to investigate the influence of interface friction on limit bulging height, wall thickness distribution, microstructure and fracture morphology of 5 A02 bulging specimens. The results showed that increase of the interface friction coefficient of 5 A02/SUS304 could effectively improve the limit bulging height and deformation uniformity of 5 A02. And the fracture style of 5 A02 transformed from toughness fracture of dimples-micropores gathered to fault slip separation fracture. Therefore, target sheet bulging formability is improved with the increase of interface friction coefficient. 展开更多
关键词 overlapping SHEETS FORMING friction coefficient FORMABILITY MICROSTRUCTURE
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Automatic fuzzy-DBSCAN algorithm for morphological and overlapping datasets 被引量:5
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作者 YELGHI Aref KÖSE Cemal +1 位作者 YELGHI Asef SHAHKAR Amir 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第6期1245-1253,共9页
Clustering is one of the unsupervised learning problems.It is a procedure which partitions data objects into groups.Many algorithms could not overcome the problems of morphology,overlapping and the large number of clu... Clustering is one of the unsupervised learning problems.It is a procedure which partitions data objects into groups.Many algorithms could not overcome the problems of morphology,overlapping and the large number of clusters at the same time.Many scientific communities have used the clustering algorithm from the perspective of density,which is one of the best methods in clustering.This study proposes a density-based spatial clustering of applications with noise(DBSCAN)algorithm based on the selected high-density areas by automatic fuzzy-DBSCAN(AFD)which works with the initialization of two parameters.AFD,by using fuzzy and DBSCAN features,is modeled by the selection of high-density areas and generates two parameters for merging and separating automatically.The two generated parameters provide a state of sub-cluster rules in the Cartesian coordinate system for the dataset.The model overcomes the problems of clustering such as morphology,overlapping,and the number of clusters in a dataset simultaneously.In the experiments,all algorithms are performed on eight data sets with 30 times of running.Three of them are related to overlapping real datasets and the rest are morphologic and synthetic datasets.It is demonstrated that the AFD algorithm outperforms other recently developed clustering algorithms. 展开更多
关键词 CLUSTERING density-based spatial clustering of applications with noise(DBSCAN) FUZZY overlapping data mining
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Dynamic interaction of twin vertically overlapping lined tunnels in an elastic half space subjected to incident plane waves 被引量:5
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作者 Zhongxian Liu Yirui Wang Jianwen Liang 《Earthquake Science》 CSCD 2016年第3期185-201,共17页
The scattering of plane harmonic P and SV waves by a pair of vertically overlapping lined tunnels buried in an elastic half space is solved using a semi-analytic indirect boundary integration equation method. Then the... The scattering of plane harmonic P and SV waves by a pair of vertically overlapping lined tunnels buried in an elastic half space is solved using a semi-analytic indirect boundary integration equation method. Then the effect of the distance between the two tunnels, the stiffness and density of the lining material, and the incident frequency on the seismic response of the tunnels is investigated. Numerical results demonstrate that the dynamic interaction between the twin tunnels cannot be ignored and the lower tunnel has a significant shielding effect on the upper tunnel for high-frequency incident waves, resulting in great decrease of the dynamic hoop stress in the upper tunnel; for the low-frequency incident waves, in contrast, the lower tunnel can lead to amplification effect on the upper tunnel. It also reveals that the frequency-spectrum characteristics of dynamic stress of the lower tunnel are significantly different from those of the upper tunnel. In addition, for incident P waves in low-frequency region, the soft lining tunnels have significant amplification effect on the surface displacement amplitude, which is slightly larger than that of the corresponding single tunnel. 展开更多
关键词 Vertically overlapping lined tunnels SCATTERING Indirect boundary integration equation method(IBIEM) Soil-tunnel dynamic interaction
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A DIAGONAL SPLIT-CELL MODEL FOR THE OVERLAPPING YEE FDTD METHOD 被引量:3
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作者 Jinjie Liu Moysey Brio Jerome V. Moloney 《Acta Mathematica Scientia》 SCIE CSCD 2009年第6期1670-1676,共7页
In this paper, we present a nonorthogonal overlapping Yee method for solv- ing Maxwell's equations using the diagonal split-cell model. When material interface is presented, the diagonal split-cell model does not req... In this paper, we present a nonorthogonal overlapping Yee method for solv- ing Maxwell's equations using the diagonal split-cell model. When material interface is presented, the diagonal split-cell model does not require permittivity averaging so that better accuracy can be achieved. Our numerical results on optical force computation show that the standard FDTD method converges linearly, while the proposed method achieves quadratic convergence and better accuracy. 展开更多
关键词 FDTD method overlapping Yee method Maxwell's equations Optical force
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