期刊文献+
共找到221,180篇文章
< 1 2 250 >
每页显示 20 50 100
Diagnosis and treatment of biliary mucinous cystic neoplasms: A single-center experience
1
作者 Jun-Jun Jia Ya-Fen Cheng +5 位作者 Mei-Bao Feng Li Liu Ming-Qi Shuai Xiao-Dong Shen Xiao-Feng Tang Shu-Sen Zheng 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第5期495-501,共7页
Background: Biliary mucinous cystic neoplasms(BMCNs) are rare hepatobiliary cystic tumors, which can be divided into noninvasive and invasive types. This study aimed to investigate the diagnosis, treatment, and progno... Background: Biliary mucinous cystic neoplasms(BMCNs) are rare hepatobiliary cystic tumors, which can be divided into noninvasive and invasive types. This study aimed to investigate the diagnosis, treatment, and prognosis of BMCNs in a large single center. Methods: We analyzed 49 patients with BMCNs confirmed by postoperative pathology at the First Afflliated Hospital, Zhejiang University School of Medicine between January 2007 and December 2021. Results: Among the 49 patients, 37 were female(75.5%), and the average age was 57.04 years. Common symptoms included abdominal discomfort, jaundice and fever, while 22 patients(44.9%) had no symptoms. Serum carbohydrate antigen(CA) 19-9 and CA125 concentrations were elevated in 34.8% and 19.6% of patients, respectively. Forty-eight patients had tumors in the intrahepatic bile ducts and only one had a tumor in the extrahepatic bile duct. Forty-eight patients with noninvasive intrahepatic BMCNs were further analyzed in terms of pathological features: 34(70.8%) had low-grade intraepithelial neoplasms(LGINs), and 14(29.2%) had high-grade intraepithelial neoplasms(HGINs). The potential immunohistochemical markers of BMCNs were cytokeratin(CK) 19, CK7, estrogen receptor and progesterone receptor. Follow-up data for 37 patients with intrahepatic BMCNs were obtained. The median overall survival(OS) of BMCNs was not reached. The longest survival time was 137 months.The 5-and 10-year OS rates were 100% and 85.4%, respectively. The 5-and 10-year recurrence-free survival(RFS) rates were 93.9% and 80.2%, respectively. Conclusions: BMCNs are rare cystic neoplasms that commonly occur in middle-aged females. BMCNs can only be diagnosed and classified by postoperative pathology, as there are no specific clinical presentations, serological indicators or imaging modalities for preoperative diagnosis. Complete surgical resection is necessary for BMCNs, and the postoperative prognosis is favorable. 展开更多
关键词 Biliary mucinous cystic neoplasms Low-grade intraepithelial neoplasms High-grade intraepithelial neoplasms Overall survival Recurrence-free survival
下载PDF
Mucinous neoplasm of the appendix:A case report and review of literature
2
作者 Hao-Cheng Chang Jung-Cheng Kang +3 位作者 Ta-Wei Pu Ruei-Yu Su Chao-Yang Chen Je-Ming Hu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第3期944-954,共11页
BACKGROUND Appendiceal mucinous neoplasms(AMNs),although not classified as rare,are relatively uncommon tumors most often discovered incidentally during colorectal surgery.Accurate identification of AMNs is difficult ... BACKGROUND Appendiceal mucinous neoplasms(AMNs),although not classified as rare,are relatively uncommon tumors most often discovered incidentally during colorectal surgery.Accurate identification of AMNs is difficult due to non-specific sym-ptoms,overlapping tumor markers with other conditions,and the potential for misdiagnosis.This underscores the urgent need for precision in diagnosis to pre-vent severe complications.CASE SUMMARY This case report describes the unexpected discovery and treatment of a low-grade AMN(LAMN)in a 74-year-old man undergoing laparoscopic hemicolectomy for transverse colon adenocarcinoma(AC).Preoperatively,non-specific gastroin-testinal symptoms and elevated tumor markers masked the presence of AMN.The tumor,presumed to be an AMN peritoneal cyst intraoperatively,was con-firmed as LAMN through histopathological examination.The neoplasm exhibited mucin accumulation and a distinct immunohistochemical profile:Positive for Ho-meobox protein CDX-2,Cytokeratin 20,special AT-rich sequence-binding protein 2,and Mucin 2 but negative for cytokeratin 7 and Paired box gene 8.This profile aids in distinguishing appendiceal and ovarian mucinous tumors.Postoperative recovery was uncomplicated,and the patient initiated adjuvant chemotherapy for the colon AC.CONCLUSION This case highlights the diagnostic complexity of AMNs,emphasizing the need for vigilant identification to avert potential complications,such as pseudomyxoma peritonei. 展开更多
关键词 Adenocarcinoma Appendiceal neoplasms Low-grade appendiceal mucinous neoplasm Peritoneal neoplasms Pseudomyxoma peritonei Case report
下载PDF
Colonoscopy plays an important role in detecting colorectal neoplasms in patients with gastric neoplasms
3
作者 Xu-Rui Liu Ze-Lin Wen +4 位作者 Fei Liu Zi-Wei Li Xiao-Yu Liu Wei Zhang Dong Peng 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第1期133-143,共11页
BACKGROUND Gastric cancer(GC)and colorectal cancer(CRC)are the fifth and third most common cancer worldwide,respectively.Nowadays,GC is reported to have a potential predictive value for CRC,especially for advanced CRC... BACKGROUND Gastric cancer(GC)and colorectal cancer(CRC)are the fifth and third most common cancer worldwide,respectively.Nowadays,GC is reported to have a potential predictive value for CRC,especially for advanced CRC.AIM To evaluate the necessity of colonoscopy for gastric neoplasm(GN)patients.METHODS Four databases,including PubMed,EMBASE,the Cochrane Library,and Ovid,were used to perform the search strategy on May 2,2023.The prevalence of colorectal neoplasms(CRN)and baseline characteristics were compared between the neoplasm group and the control group.Continuous variables are expressed as the mean difference and standard deviation.Relationships of categorical variables in the two groups are expressed as odds ratios(OR)and 95%confidence intervals(95%CIs).Subgroup analysis according to different kinds of GNs was conducted for more in-depth analysis.The results of this study are represented by forest plots.Publication bias was evaluated by a funnel plot.All data analyses were performed by STATA SE 16.0 software.RESULTS A total of 3018 patients with GNs and 3905 healthy controls(age and sex matched)were enrolled for analysis.After comparing the prevalence of CRNs between the two groups,CRNs were detected significantly more frequently in GN patients than in controls(OR=1.69,95%CI=1.28 to 2.23,I^(2)=85.12%,P=0.00),especially in patients with GC(OR=1.80,95%CI=1.49 to 2.18,I^(2)=25.55%,P<0.1).Moreover,other risk factors including age(OR=1.08,95%CI=1.00 to 1.17,I^(2)=90.13%,P=0.00)and male sex(OR=2.31,95%CI=1.26 to 4.22,I^(2)=87.35%,P=0.00),were related to the prevalence of CRNs.For patients in the GN group,body mass index(BMI,OR=0.88,95%CI=0.80 to 0.98,I^(2)=0.00%,P=0.92)and smoking(OR=1.03,95%CI=1.01 to 1.05,I^(2)=0.00%,P=0.57)were protective and risk factors for CRNs,respectively.CONCLUSION Patients are recommended to undergo colonoscopy when diagnosed with GNs,especially GC patients with a low BMI and a history of smoking. 展开更多
关键词 Gastric neoplasm Gastric cancer Colorectal neoplasm COLONOSCOPY
下载PDF
A Review of Type 1 and Type 2 Intraductal Papillary Neoplasms of the Bile Duct
4
作者 Xia-hui HUANG Tian-xiang CHEN +1 位作者 Hong-liang LIU Ming-wen HUANG 《Current Medical Science》 SCIE CAS 2024年第3期485-493,共9页
Intraductal papillary neoplasm of the bile duct(IPNB)is a heterogeneous disease similar to intraductal papillary mucinous neoplasm of the pancreas.These lesions have been recognized as one of the three major precancer... Intraductal papillary neoplasm of the bile duct(IPNB)is a heterogeneous disease similar to intraductal papillary mucinous neoplasm of the pancreas.These lesions have been recognized as one of the three major precancerous lesions in the biliary tract since 2010.In 2018,Japanese and Korean pathologists reached a consensus,classifying IPNBs into type l and type 2 IPNBs.IPNBs are more prevalent in male patients in East Asia and are closely related to diseases such as cholelithiasis and schistosomiasis.From a molecular genetic perspective,IPNBs exhibit early genetic variations,and different molecular pathways may be involved in the tumorigenesis of type 1 and type 2 IPNBs.The histological subtypes of IPNBs include gastric,intestinal,pancreaticobiliary,or oncocytic subtypes,but type 1 IPNBs typically exhibit more regular and well-organized histological features than type 2 IPNBs and are more commonly found in the intrahepatic bile ducts with abundant mucin.Due to the rarity of these lesions and the absence of specific clinical and laboratory features,imaging is crucial for the preoperative diagnosis of IPNB,with local bile duct dilation and growth along the bile ducts being the main imaging features.Surgical resection remains the optimal treatment for IPNBs,but negative bile duct margins and the removal of lymph nodes in the hepatic hilum significantly improve the postoperative survival rates for patients with IPNBs. 展开更多
关键词 intraductal papillary neoplasm of the bile duct SUBCLASSIFICATION neoplasmS precancerous tissue PROGNOSIS
下载PDF
Current considerations on intraductal papillary neoplasms of the bile duct and pancreatic duct
5
作者 Efstathios T Pavlidis Ioannis N Galanis Theodoros E Pavlidis 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1461-1465,共5页
Pancreatobiliary intraductal papillary neoplasms(IPNs)represent precursors of pancreatic cancer or bile duct cholangiocarcinoma that can be detected and treated.Despite advances in diagnostic methods,identifying these... Pancreatobiliary intraductal papillary neoplasms(IPNs)represent precursors of pancreatic cancer or bile duct cholangiocarcinoma that can be detected and treated.Despite advances in diagnostic methods,identifying these premalignant lesions is still challenging for treatment providers.Modern imaging,biomarkers and molecular tests for genomic alterations can be used for diagnosis and follow-up.Surgical intervention in combination with new chemotherapeutic agents is considered the optimal treatment for malignant cases.The balance between the risk of malignancy and any risk of resection guides management policy;therefore,treatment should be individualized based on a meticulous preoperative assessment of high-risk stigmata.IPN of the bile duct is more aggressive;thus,early diagnosis and surgery are crucial.The conservative management of low-risk pancreatic branch-duct lesions is safe and effective. 展开更多
关键词 Biliary tree diseases Pancreatic cystic neoplasms Biliary tract neoplasms Extrahepatic cholangiocarcinoma Pancreatic adenocarcinoma
下载PDF
An Rapid Assessment Method for Bearing Capacity of RC Girder Bridges Based on Residual Strain
6
作者 Ming Zhong 《Open Journal of Civil Engineering》 2024年第2期225-239,共15页
In order to realize the in-situ evaluation of reinforced concrete bridges subjected to fatigue for a long time or after earthquake, an evaluation method for cumulative damage of concrete structures based on unloading ... In order to realize the in-situ evaluation of reinforced concrete bridges subjected to fatigue for a long time or after earthquake, an evaluation method for cumulative damage of concrete structures based on unloading elastic modulus was proposed. First, according to the concrete stress-strain curve and the statistical relationship between residual strain and cumulative strain, the calculation method of static equivalent strain and residual strain concrete based on unloading elastic modulus and the method for estimating the strength of concrete after damage were proposed. The detailed steps of field test and analysis and the practical damage indicators of residual strain were given. Then, the evaluation method of existing stress and strain of Reinforced Concrete Bridge under dead load and the concept of “equivalent dead load bending moment” were put forward. On this basis, the paper analyzed the root cause of the decrease of bearing capacity of Reinforced Concrete Bridge after fatigue damage, and pointed out that the equivalent strain or residual strain of reinforced concrete increases under the fatigue effect, which led to the decreasing of actual live moment and deformation performance while the ultimate load-carrying capacity remained constant or very little decrease. The evaluation method of structure residual capacity was given, and through comparative analysis of eight T reinforced concrete beams that had been in service for 35 years with the static failure tests, the effectiveness of the method was verified. 展开更多
关键词 Bridge Engineering Reinforced Concrete Fatigue Damage Unloading Elastic Modulus residual Strain residual Bearing Capacity
下载PDF
Structural properties of residual carbon in coal gasification fine slag and their influence on flotation separation and resource utilization:A review 被引量:3
7
作者 Rui Han Anning Zhou +4 位作者 Ningning Zhang Kaiqiang Guo Mengyan Cheng Heng Chen Cuicui Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期217-230,共14页
Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery a... Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery and the high-value utilization of residual carbon(RC)in FS are the keys to realizing the win-win situation of the coal chemical industry in terms of economic and environmental benefits.The structural properties,such as pore,surface functional group,and microcrystalline structures,of RC in FS(FS-RC)not only affect the flotation recovery efficiency of FS-RC but also form the basis for the high-value utilization of FS-RC.In this paper,the characteristics of FS-RC in terms of pore structure,surface functional groups,and microcrystalline structure are sorted out in accordance with gasification type and FS particle size.The reasons for the formation of the special structural properties of FS-RC are analyzed,and their influence on the flotation separation and high-value utilization of FS-RC is summarized.Separation methods based on the pore structural characterist-ics of FS-RC,such as ultrasonic pretreatment-pore-blocking flotation and pore breaking-flocculation flotation,are proposed to be the key development technologies for improving FS-RC recovery in the future.The design of low-cost,low-dose collectors containing polar bonds based on the surface and microcrystalline structures of FS-RC is proposed to be an important breakthrough point for strengthening the flotation efficiency of FS-RC in the future.The high-value utilization of FS should be based on the physicochemical structural proper-ties of FS-RC and should focus on the environmental impact of hazardous elements and the recyclability of chemical waste liquid to es-tablish an environmentally friendly utilization method.This review is of great theoretical importance for the comprehensive understand-ing of the unique structural properties of FS-RC,the breakthrough of the technological bottleneck in the efficient flotation separation of FS,and the expansion of the field of the high value-added utilization of FS-RC. 展开更多
关键词 coal gasification fine slag residual carbon pore structure surface functional groups microcrystalline structure flotation sep-aration resource utilization
下载PDF
Endoscopic ultrasonography-related diagnostic accuracy and clinical significance on small rectal neuroendocrine neoplasms 被引量:1
8
作者 Jun Weng Yu-Fan Chen +5 位作者 Shu-Han Li Yan-Hua Lv Ruo-Bing Chen Guo-Liang Xu Shi-Yong Lin Kun-Hao Bai 《World Journal of Gastroenterology》 SCIE CAS 2024年第7期774-778,共5页
This research aimed to examine the diagnostic accuracy and clinical significance of endoscopic ultrasonography(EUS)in the context of small rectal neuroendocrine neoplasms(NENs).A total of 108 patients with rectal sube... This research aimed to examine the diagnostic accuracy and clinical significance of endoscopic ultrasonography(EUS)in the context of small rectal neuroendocrine neoplasms(NENs).A total of 108 patients with rectal subepithelial lesions(SELs)with a diameter of<20 mm were included in the analysis.The diagnosis and depth assessment of EUS was compared to the histology findings.The prevalence of NENs in rectal SELs was 78.7%(85/108).The sensitivity of EUS in detecting rectal NENs was 98.9%(84/85),while the specificity was 52.2%(12/23).Overall,the diagnostic accuracy of EUS in identifying rectal NENs was 88.9%(96/108).The overall accuracy rate for EUS in assessing the depth of invasion in rectal NENs was 92.9%(78/84).Therefore,EUS demonstrates reasonable diagnostic accuracy in detecting small rectal NENs,with good sensitivity but inferior specificity.EUS may also assist physicians in assessing the depth of invasion in small rectal NENs before endoscopic excision. 展开更多
关键词 Rectal neuroendocrine neoplasms Endoscopic ultrasonography DIAGNOSIS Depth of invasion
下载PDF
Tri-modal death distribution towards personalized management of intraductal papillary neoplasm of the bile duct patients:Every story has its own conclusion
9
作者 Vor Luvira 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第3期313-316,共4页
The concept of intraductal papillary neoplasm of the bile duct(IPNB)has gained recognition as a discrete entity[1,2],possessing many features including multiplicity[3,4],mucin production[3],slow progression[3,5],vario... The concept of intraductal papillary neoplasm of the bile duct(IPNB)has gained recognition as a discrete entity[1,2],possessing many features including multiplicity[3,4],mucin production[3],slow progression[3,5],various morphology[6,7],easy sloughing and seeding[8],and having unique risk factors[2,9-11].We have previously proposed a morphologic classification[6]and a progression model of IPNB[12]. 展开更多
关键词 neoplasm BILE CONCLUSION
下载PDF
Residual stress modeling of mitigated fused silica damage sites with CO_(2)laser annealing
10
作者 张传超 廖威 +3 位作者 张丽娟 蒋晓龙 方振华 蒋晓东 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期509-514,共6页
A numerical model based on measured fictive temperature distributions is explored to evaluate the residual stress fields of CO_(2)laser-annealed mitigated fused silica damage sites.The proposed model extracts the resi... A numerical model based on measured fictive temperature distributions is explored to evaluate the residual stress fields of CO_(2)laser-annealed mitigated fused silica damage sites.The proposed model extracts the residual strain from the differences in thermoelastic contraction of fused silica with different fictive temperatures from the initial frozen-in temperatures to ambient temperature.The residual stress fields of mitigated damage sites for the CO_(2)laser-annealed case are obtained by a finite element analysis of equilibrium equations and constitutive equations.The simulated results indicate that the proposed model can accurately evaluate the residual stress fields of laser-annealed mitigated damage sites with a complex thermal history.The calculated maximum hoop stress is in good agreement with the reported experimental result.The estimated optical retardance profiles from the calculated radial and hoop stress fields are consistent with the photoelastic measurements.These results provide sufficient evidence to demonstrate the suitability of the proposed model for describing the residual stresses of mitigated fused silica damage sites after CO_(2)laser annealing. 展开更多
关键词 fused silica damage mitigation residual stress laser annealing
下载PDF
Molecular simulation study on the evolution process of hydrate residual structures into hydrate
11
作者 Liwei Cheng Yunfei Li +4 位作者 Jinlong Cui Huibo Qin Fulong Ning Bei Liu Guangjin Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期79-91,共13页
The clathrate hydrate memory effect is a fascinating phenomenon with potential applications in carbon capture,utilization and storage(CCUS),gas separation,and gas storage as it can accelerate the secondary formation o... The clathrate hydrate memory effect is a fascinating phenomenon with potential applications in carbon capture,utilization and storage(CCUS),gas separation,and gas storage as it can accelerate the secondary formation of clathrate hydrate.However,the underlying mechanism of this effect remains unclear.To gain a better understanding of the mechanism,we conducted molecular dynamic simulations to simulate the initial formation and reformation processes of methane hydrate.In this work,we showed the evolution process of hydrate residual structures into hydrate cages.The simulation results indicate that the residual structures are closely related to the existence of hydrate memory effect,and the higher the contribution of hydrate dissociated water to the hydrate nucleation process,the faster the hydrate nucleation.After hydrate dissociation,the locally ordered structures still exist after hydrate dissociation and can promote the formation of cluster structures,thus accelerating hydrate nucleation.Additionally,the nucleation process of hydrate and the formation process of clusters are inseparable.The size of clusters composed of cup-cage structures is critical for hydrate nucleation.The residence time at high temperature after hydrate decomposition will affect the strength of the hydrate memory effect.Our simulation results provide microscopic insights into the occurrence of the hydrate memory effect and shed light on the hydrate reformation process at the molecular scale. 展开更多
关键词 Memory effect Molecular simulation Hydrate reformation residual structures
下载PDF
Residual alkali-evoked cross-linked polymer layer for anti-air-sensitivity LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)cathode
12
作者 Chao Zhao Xuebao Li +7 位作者 Yun Zhao Jingjing He Yuanpeng Cao Wei Luo Ding Wang Jianguo Duan Xianshu Wang Baohua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期450-458,共9页
High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)M... High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)faces challenges related to capacity decay caused by residual alkalis owing to high sensitivity to air.To address this issue,we propose a hazardous substances upcycling method that fundamentally mitigates alkali content and concurrently induces the emergence of an anti-air-sensitive layer on the cathode surface.Through the neutralization of polyacrylic acid(PAA)with residual alkalis and then coupling it with 3-aminopropyl triethoxysilane(KH550),a stable and ion-conductive cross-linked polymer layer is in situ integrated into the LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)(NCM)cathode.Our characterization and measurements demonstrate its effectiveness.The NCM material exhibits impressive cycling performance,retaining 88.4%of its capacity after 200 cycles at 5 C and achieving an extraordinary specific capacity of 170.0 mA h g^(-1) at 10 C.Importantly,this layer on the NCM efficiently suppresses unfavorable phase transitions,severe electrolyte degradation,and CO_(2)gas evolution,while maintaining commendable resistance to air exposure.This surface modification strategy shows widespread potential for creating air-stable LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)cathodes,thereby advancing high-performance LIBs. 展开更多
关键词 Lithium-ion batteries Nickel-rich layered cathode residual alkalis Cross-linked polyme rmodification Airsensitivity
下载PDF
Effects of soil crust on the collapsing erosion of colluvial deposits with granite residual soil
13
作者 LIU Weiping ZENG Bohan +1 位作者 WANG Tianhuan DUAN Junyi 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2579-2591,共13页
Collapsing erosion is a unique phenomenon commonly observed on the granite residue hillslopes in the tropical and subtropical regions of southern China,characterized by its abrupt occurrence and significant erosion vo... Collapsing erosion is a unique phenomenon commonly observed on the granite residue hillslopes in the tropical and subtropical regions of southern China,characterized by its abrupt occurrence and significant erosion volumes.However,the impacts of soil crust conditions on the erosion of colluvial deposits with granite residual soils have only been studied to a limited extent.To address this issue,this study investigates the impacts of three soil crust conditions(i.e.,without crust,10-minute crust,and 20-minute crust)on gully morphology,rainfall infiltration,and runoff and sediment yield during slope erosion of colluvial deposits with granite residues(classified as Acrisols)in Yudu County,Ganzhou City,Jiangxi Province,China,using simulated rainfall tests and photographic methods.The results showed that as the strength of the soil crust increased,the capacity of moisture infiltration and the width and depth of the gully as well as the sediment concentration and yield ratio decreased;at the same time,the runoff ratio increased.The sediment yield in the without-crust test was found to be 1.24 and 1.43 times higher than that observed in the 10-minute crust and 20-minute crust tests,respectively.These results indicate that soil crusts can effectively prevent slope erosion and moisture infiltration,while providing valuable insights for the management of soil erosion in natural environments. 展开更多
关键词 Granite residual soil Colluvial deposits Slope erosion Soil crust Sediment yield
下载PDF
A modified smoothed particle hydrodynamics method considering residual stress for simulating failure and its application in layered rock mass
14
作者 XIA Chengzhi SHI Zhenming KOU Huanjia 《Journal of Mountain Science》 SCIE CSCD 2024年第6期2091-2112,共22页
Residual strength is an indispensable factor in evaluating rock fracture,yet the current Smoothed Particle Hydrodynamics(SPH)framework rarely considers its influence when simulating fracture.An improved cracking strat... Residual strength is an indispensable factor in evaluating rock fracture,yet the current Smoothed Particle Hydrodynamics(SPH)framework rarely considers its influence when simulating fracture.An improved cracking strategy considering residual stress in the base bond SPH method was proposed to simulate failures in layered rocks and slopes and verified by experimental results and other simulation methods(i.e.,the discrete element method).Modified Mohr–Coulomb failure criterion was applied to distinguish the mixed failure of tensile and shear.Bond fracture markψwas introduced to improve the kernel function after tensile damage,and the calculation of residual stress after the damage was derived after shear damage.Numerical simulations were carried out to evaluate its performance under different stress and scale conditions and to verify its effectiveness in realistically reproducing crack initiation and propagation and coalescence,even fracture and separation.The results indicate that the improved cracking strategy precisely captures the fracture and failure pattern in layered rocks and rock slopes.The residual stress of brittle tock is correctly captured by the improved SPH method.The improved SPH method that considers residual strength shows an approximately 13%improvement in accuracy for the safety factor of anti-dip layered slopes compared to the method that does not consider residual strength,as validated against analytical solutions.We infer that the improved SPH method is effective and shows promise for applications to continuous and discontinuous rock masses. 展开更多
关键词 Smoothed particle hydrodynamics Cracking strategy residual stress Layered rock Crack propagation
下载PDF
Attention-Based Residual Dense Shrinkage Network for ECG Denoising
15
作者 Dengyong Zhang Minzhi Yuan +3 位作者 Feng Li Lebing Zhang Yanqiang Sun Yiming Ling 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2809-2824,共16页
Electrocardiogram(ECG)signal is one of the noninvasive physiological measurement techniques commonly usedin cardiac diagnosis.However,in real scenarios,the ECGsignal is susceptible to various noise erosion,which affec... Electrocardiogram(ECG)signal is one of the noninvasive physiological measurement techniques commonly usedin cardiac diagnosis.However,in real scenarios,the ECGsignal is susceptible to various noise erosion,which affectsthe subsequent pathological analysis.Therefore,the effective removal of the noise from ECG signals has becomea top priority in cardiac diagnostic research.Aiming at the problem of incomplete signal shape retention andlow signal-to-noise ratio(SNR)after denoising,a novel ECG denoising network,named attention-based residualdense shrinkage network(ARDSN),is proposed in this paper.Firstly,the shallow ECG characteristics are extractedby a shallow feature extraction network(SFEN).Then,the residual dense shrinkage attention block(RDSAB)isused for adaptive noise suppression.Finally,feature fusion representation(FFR)is performed on the hierarchicalfeatures extracted by a series of RDSABs to reconstruct the de-noised ECG signal.Experiments on the MIT-BIHarrhythmia database and MIT-BIH noise stress test database indicate that the proposed scheme can effectively resistthe interference of different sources of noise on the ECG signal. 展开更多
关键词 Electrocardiogram signal denoising signal-to-noise ratio attention-based residual dense shrinkage network MIT-BIH
下载PDF
Ghost Module Based Residual Mixture of Self-Attention and Convolution for Online Signature Verification
16
作者 Fangjun Luan Xuewen Mu Shuai Yuan 《Computers, Materials & Continua》 SCIE EI 2024年第4期695-712,共18页
Online Signature Verification (OSV), as a personal identification technology, is widely used in various industries.However, it faces challenges, such as incomplete feature extraction, low accuracy, and computational h... Online Signature Verification (OSV), as a personal identification technology, is widely used in various industries.However, it faces challenges, such as incomplete feature extraction, low accuracy, and computational heaviness. Toaddress these issues, we propose a novel approach for online signature verification, using a one-dimensionalGhost-ACmix Residual Network (1D-ACGRNet), which is a Ghost-ACmix Residual Network that combines convolutionwith a self-attention mechanism and performs improvement by using Ghost method. The Ghost-ACmix Residualstructure is introduced to leverage both self-attention and convolution mechanisms for capturing global featureinformation and extracting local information, effectively complementing whole and local signature features andmitigating the problem of insufficient feature extraction. Then, the Ghost-based Convolution and Self-Attention(ACG) block is proposed to simplify the common parts between convolution and self-attention using the Ghostmodule and employ feature transformation to obtain intermediate features, thus reducing computational costs.Additionally, feature selection is performed using the random forestmethod, and the data is dimensionally reducedusing Principal Component Analysis (PCA). Finally, tests are implemented on the MCYT-100 datasets and theSVC-2004 Task2 datasets, and the equal error rates (EERs) for small-sample training using five genuine andforged signatures are 3.07% and 4.17%, respectively. The EERs for training with ten genuine and forged signaturesare 0.91% and 2.12% on the respective datasets. The experimental results illustrate that the proposed approacheffectively enhances the accuracy of online signature verification. 展开更多
关键词 Online signature verification feature selection ACG block ghost-ACmix residual structure
下载PDF
Abnormal Traffic Detection for Internet of Things Based on an Improved Residual Network
17
作者 Tingting Su Jia Wang +2 位作者 Wei Hu Gaoqiang Dong Jeon Gwanggil 《Computers, Materials & Continua》 SCIE EI 2024年第6期4433-4448,共16页
Along with the progression of Internet of Things(IoT)technology,network terminals are becoming continuously more intelligent.IoT has been widely applied in various scenarios,including urban infrastructure,transportati... Along with the progression of Internet of Things(IoT)technology,network terminals are becoming continuously more intelligent.IoT has been widely applied in various scenarios,including urban infrastructure,transportation,industry,personal life,and other socio-economic fields.The introduction of deep learning has brought new security challenges,like an increment in abnormal traffic,which threatens network security.Insufficient feature extraction leads to less accurate classification results.In abnormal traffic detection,the data of network traffic is high-dimensional and complex.This data not only increases the computational burden of model training but also makes information extraction more difficult.To address these issues,this paper proposes an MD-MRD-ResNeXt model for abnormal network traffic detection.To fully utilize the multi-scale information in network traffic,a Multi-scale Dilated feature extraction(MD)block is introduced.This module can effectively understand and process information at various scales and uses dilated convolution technology to significantly broaden the model’s receptive field.The proposed Max-feature-map Residual with Dual-channel pooling(MRD)block integrates the maximum feature map with the residual block.This module ensures the model focuses on key information,thereby optimizing computational efficiency and reducing unnecessary information redundancy.Experimental results show that compared to the latest methods,the proposed abnormal traffic detection model improves accuracy by about 2%. 展开更多
关键词 Abnormal network traffic deep learning residual network multi-scale feature extraction max-feature-map
下载PDF
Workout Action Recognition in Video Streams Using an Attention Driven Residual DC-GRU Network
18
作者 Arnab Dey Samit Biswas Dac-Nhuong Le 《Computers, Materials & Continua》 SCIE EI 2024年第5期3067-3087,共21页
Regular exercise is a crucial aspect of daily life, as it enables individuals to stay physically active, lowers thelikelihood of developing illnesses, and enhances life expectancy. The recognition of workout actions i... Regular exercise is a crucial aspect of daily life, as it enables individuals to stay physically active, lowers thelikelihood of developing illnesses, and enhances life expectancy. The recognition of workout actions in videostreams holds significant importance in computer vision research, as it aims to enhance exercise adherence, enableinstant recognition, advance fitness tracking technologies, and optimize fitness routines. However, existing actiondatasets often lack diversity and specificity for workout actions, hindering the development of accurate recognitionmodels. To address this gap, the Workout Action Video dataset (WAVd) has been introduced as a significantcontribution. WAVd comprises a diverse collection of labeled workout action videos, meticulously curated toencompass various exercises performed by numerous individuals in different settings. This research proposes aninnovative framework based on the Attention driven Residual Deep Convolutional-Gated Recurrent Unit (ResDCGRU)network for workout action recognition in video streams. Unlike image-based action recognition, videoscontain spatio-temporal information, making the task more complex and challenging. While substantial progresshas been made in this area, challenges persist in detecting subtle and complex actions, handling occlusions,and managing the computational demands of deep learning approaches. The proposed ResDC-GRU Attentionmodel demonstrated exceptional classification performance with 95.81% accuracy in classifying workout actionvideos and also outperformed various state-of-the-art models. The method also yielded 81.6%, 97.2%, 95.6%, and93.2% accuracy on established benchmark datasets, namely HMDB51, Youtube Actions, UCF50, and UCF101,respectively, showcasing its superiority and robustness in action recognition. The findings suggest practicalimplications in real-world scenarios where precise video action recognition is paramount, addressing the persistingchallenges in the field. TheWAVd dataset serves as a catalyst for the development ofmore robust and effective fitnesstracking systems and ultimately promotes healthier lifestyles through improved exercise monitoring and analysis. 展开更多
关键词 Workout action recognition video stream action recognition residual network GRU ATTENTION
下载PDF
Radar Signal Intra-Pulse Modulation Recognition Based on Deep Residual Network
19
作者 Fuyuan Xu Guangqing Shao +3 位作者 Jiazhan Lu Zhiyin Wang Zhipeng Wu Shuhang Xia 《Journal of Beijing Institute of Technology》 EI CAS 2024年第2期155-162,共8页
In view of low recognition rate of complex radar intra-pulse modulation signal type by traditional methods under low signal-to-noise ratio(SNR),the paper proposes an automatic recog-nition method of complex radar intr... In view of low recognition rate of complex radar intra-pulse modulation signal type by traditional methods under low signal-to-noise ratio(SNR),the paper proposes an automatic recog-nition method of complex radar intra-pulse modulation signal type based on deep residual network.The basic principle of the recognition method is to obtain the transformation relationship between the time and frequency of complex radar intra-pulse modulation signal through short-time Fourier transform(STFT),and then design an appropriate deep residual network to extract the features of the time-frequency map and complete a variety of complex intra-pulse modulation signal type recognition.In addition,in order to improve the generalization ability of the proposed method,label smoothing and L2 regularization are introduced.The simulation results show that the proposed method has a recognition accuracy of more than 95%for complex radar intra-pulse modulation sig-nal types under low SNR(2 dB). 展开更多
关键词 intra-pulse modulation low signal-to-noise deep residual network automatic recognition
下载PDF
Transcatheter Closure of Postoperative Residual Atrial or Ventricular Septal Shunts in Patients with Congenital Heart Disease
20
作者 Jiawang Xiao Jianming Wang +3 位作者 Zhongchao Wang Lili Meng Ming Zhao Qiguang Wang 《Congenital Heart Disease》 SCIE 2024年第3期293-303,共11页
Background:Transcatheter closure(TCC)has emerged as the preferred treatment for selected congenital heart disease(CHD).While TCC offers benefits for patients with postoperative residual shunts,understanding its mid-and... Background:Transcatheter closure(TCC)has emerged as the preferred treatment for selected congenital heart disease(CHD).While TCC offers benefits for patients with postoperative residual shunts,understanding its mid-and long-term efficacy and safety remains crucial.Objective:This study aims to assess the mid-and long-term safety and efficacy of TCC for patients with residual atrial or ventricular septal shunts following CHD correction.Methods:In this consecutive retrospective study,we enrolled 35 patients with residual shunt who underwent TCC or surgical repair of CHD between June 2011 to October 2022.TCC candidacy was determined based on established criteria.Echocardiography and electrocardiogram were conducted during the perioperative period and continued as part of long-term follow-up.Results:Among the patients,5(14.3%)exhibited interatrial shunt-ing,while 30(85.7%)had interventricular shunting.TCC was successfully implemented in 33 of 35 patients,with exceptions in two cases of post-ventricular septal defect repair due to anatomical challenges involving the shape and aortic angulation.This resulted in a TCC success rate of 94.3%.Trace residual shunt was detected in two interventricular shunting cases and a mild residual shunt in one interventricular shunting case;all resolved by the three-month follow-up after TCC.Minor complications included one hematoma at the puncture site and one transient junctional rhythm during the perioperative period.During a median follow-up of 73 months,there were no instances of residual shunt,device embolization,occluder displacement,valve insufficiency,malignant arrhythmia,infective endocarditis,death,or other serious complications.Conclusion:TCC is an effective and safe therapy for patients with residual atrial or ventricular septal shunts following CHD correction.Thesefindings support the consideration of TCC as the preferred treatment option for appropriate patient populations. 展开更多
关键词 Congenital heart disease residual shunt transcatheter closure surgical repair
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部