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A Preliminary Clinical Study of Three Dimensional Ultrasonography in Prenatal Diagnosis
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作者 徐辉雄 张青萍 +3 位作者 肖先桃 闻良珍 许建平 陈欣林 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2001年第4期341-344,348,共5页
To evaluate the clinical value of three dimensional ultrasonography (3DUS) in prenatal diagnosis, 134 pregnant women with high risk factors in second and third trimester were examined by 3DUS. The results showed tha... To evaluate the clinical value of three dimensional ultrasonography (3DUS) in prenatal diagnosis, 134 pregnant women with high risk factors in second and third trimester were examined by 3DUS. The results showed that 3DUS could provide more diagnostic information, exclude the abnormalities and enhance the confidence level of physician in 102 normal pregnant women. 3DUS was helpful in the diagnosis in 17 (60.7 %) of 28 cases of fetal anomalies. However, 3DUS was not useful in evaluating intrauterine growth retardation in 4 cases. It is conclucded that 3DUS is helpful in prenatal diagnosis. 展开更多
关键词 three dimensional ultrasonography FETUS OBSTETRICS prenatal diagnosis
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Three-dimensional patient-derived cell models represent an emerging frontier in the study of neurodegenerative diseases
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作者 Rachel J.Boyd Vasiliki Mahairaki 《Neural Regeneration Research》 2026年第6期2327-2328,共2页
Neurodegenerative disorders represent an increasingly pertinent public health crisis.As a greater proportion of the population ages,neurodegenerative disorders and other diseases of aging place undue burdens on patien... Neurodegenerative disorders represent an increasingly pertinent public health crisis.As a greater proportion of the population ages,neurodegenerative disorders and other diseases of aging place undue burdens on patients,caregivers,and healthcare workers.Alzheimer’s disease(AD)and Parkinson’s disease represent the two most common neurodegenerative disorders in the population,affecting over 65 million people,worldwide. 展开更多
关键词 Alzheimer s disease public health crisis neurodegenerative diseases neurodegenerative disorders parkinson s disease aging three dimensional patient derived cell models
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Erratum:Bone Regeneration Eff cacy and Applicability of Defect-Fitting 4D Scaffolds Based on Shape Conformity in Three-dimensional Curved Bone Defects
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作者 Min-Soo Ghim Se-Jin Jang +3 位作者 Eun-Yong Choi Meiling Quan Young-Yul Kim Young-Sam Cho 《Journal of Bionic Engineering》 2026年第1期550-550,共1页
The original online version of this article was revised:The layout update for Article 758 has impacted the page range in the published issue,but did not affect the scholarly content.To ensure consistency with the orig... The original online version of this article was revised:The layout update for Article 758 has impacted the page range in the published issue,but did not affect the scholarly content.To ensure consistency with the originally assigned pages(2595-2614),we will need to publish an erratum to correct the article and restore the original page range.The original article has been corrected. 展开更多
关键词 defect fitting D scaffolds layout update shape conformity three dimensional curved bone defects bone regeneration
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Correction to: Tuning dual three-dimensional porous copper/graphite composite to achieve diversified utilization of copper current collector for lithium storage
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作者 Xia Ma Zhi-Jia Zhang +7 位作者 Jia-Min Wang Shi-Hao Sun Shao-Fei Zhang Shen Yuan Zhi-Jun Qiao Zhen-Yang Yu Jian-Li Kang Wei-Jie Li 《Rare Metals》 2025年第2期1409-1409,共1页
In the original publication, incomplete Fig. 1 has been published. The correct version of Fig. 1 is provided in this correction.
关键词 GRAPHITE tuning COMPOSITE three dimensional current collector POROUS DUAL COPPER
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Three-dimensional location approach with silk thread guided hepatectomy for liver tumor
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作者 Zhi-Hong Zhang Qing-Bo Feng +2 位作者 Chuang Jiang Ji-Wei Huang Jia-Xin Li 《World Journal of Gastroenterology》 2025年第8期66-71,共6页
BACKGROUND Intraoperative determination of resection margin and adequate residual liver parenchyma are the key points of hepatectomy for the treatment of liver tumors.Intraoperative ultrasound and indocyanine green fl... BACKGROUND Intraoperative determination of resection margin and adequate residual liver parenchyma are the key points of hepatectomy for the treatment of liver tumors.Intraoperative ultrasound and indocyanine green fluorescence navigation are the most commonly used methods at present,but the technical barriers limit their promotion.AIM To evaluate the value of the three-dimensional location approach with silk thread(3D-LAST)in precise resection of liver tumors.METHODS From September 2020 to January 2022,8 patients with liver tumors including hepatocellular carcinoma,intrahepatic cholangiocarcinoma,hilar cholangiocar-cinoma,and gastric cancer liver metastasis were included in this study.All patients underwent 3D-LAST in precise resection of liver tumors.RESULTS All patients(8/8,100%)underwent the operation successfully without any complications.During the mean follow-up of 8.7 months,all patients survived without tumor recurrence.CONCLUSION In conclusion,the 3D-LAST is a safe and effective new method for liver intraop-erative navigation,which is practical and easy to promote.Core Tip:The aim of this study is to evaluate the value of the three-dimensional location approach with silk thread(3D-LAST)in precise resection of liver tumors.Eight patients with liver tumors including hepatocellular carcinoma,intrahepatic cholangiocarcinoma,hilar cholangiocarcinoma,and gastric cancer liver metastasis underwent the operation successfully without any complications.During the mean follow-up of 8.7 months,all patients survived without tumor recurrence.In conclusion,the 3D-LAST is a safe and effective new method for liver intraoperative navigation,which is practical and easy to promote.INTRODUCTION Hepatectomy is widely used for the treatment of liver tumors.In recent decades,the concept and practice of hepatectomy have developed from irregular,regular and anatomical to the current precise resection.Necessary assistive technologies have enabled these advances.Intraoperative ultrasound(IOUS)localization and indocyanine green(ICG)fluorescence imaging guidance are two frequently-used approaches for laparoscopic hepatectomy[1,2].IOUS is an invaluable auxiliary means widely accepted in surgery for real-time diagnostic information to determine resection range and navigate the surgical path[3].However,the major limitation of IOUS is the time cost during the procedure for paging the sono-graphers and the difficulty of deciphering two dimensional images[4].ICG is a non-toxic water-soluble fluorophore that reveals fluorescence under the near-infrared spectrum[5].Since liver tissue penetration is limited to 5 to 10 mm,that restricted the visualization of deeper tumors by ICG excitation,thereby interfering with its application in laparoscopic hepatectomy[6].IOUS and ICG navigation require specific technical equipment,making implementation difficult in many centers.And these techniques will significantly increase the operation time.Three-dimensional(3D)visualization involves extracting features and producing volumetric images based on computed tomography(CT)through a computer postprocessing technique.This tool offers a reasonable approach to the clinical decision for the potential to display the complex internal anatomy in an intuitive and stereoscopic manner[7].In the past few decades,applying 3D simulation software for liver volume calculation,virtual simulation surgery,portal hypertension monitor,and surgical navigation has proven to be safe and effective[8].Therefore,we propose a new method to find obvious anatomical markers and calculate the resection range according to 3D positioning before operation.During the operation,the scope of resection was delineated with silk thread,and resection was performed.This is a new practical approach,which we named as 3D location approach with silk thread(3D-LAST).RESULTS During the study period from September 2020 to January 2022,5 patients with hepatocellular carcinoma,1 patient with intrahepatic cholangiocarcinoma,1 patient with hilar cholangiocarcinoma,and 1 patient with gastric cancer liver metastasis were assessed for liver resection.There were 5 males and 3 females.The mean age of these patients was 54.3±10.2 years(34-66 years).Preoperative 3D positioning was conducted and the scope of resection was delineated with a surgical suture successfully performed in all 8 patients without complications.The treatment results of these 8 patients are shown in Table 1.The 90-day operative mortality was zero.Complications worse than Dindo-Clavien IIIa was not observed at a mean follow-up time of 8.7 months(4-16 months),there was no evidence of tumor recurrence or extrahepatic metastasis.At the time of reporting,the patients are all alive and lead normal lives.We take one patient as an example,58-year-old male,who found a liver lesion 10 months after gastric cancer surgery.Enhanced CT showed that the lesion was located in the liver S5,about 1.5 cm in diameter,and considered metastatic lesions.We performed 3D-LAST guided hepatectomy on this patient(Figure 1).Other representative 3D-LAST surgical procedures are shown in Figure 2. 展开更多
关键词 HEPATECTOMY LAPAROSCOPY Liver tumor three dimensional Silk thread
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Application of two modified three-dimensional printed models in liver surgery
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作者 Cheng Quan Zhi-Ming Hu +2 位作者 Xue-Yuan Jiang Qing Han Yu Wang 《Hepatobiliary & Pancreatic Diseases International》 2025年第4期452-454,共3页
The anatomy of the human liver is complex,and the vascular system is highly variable.Moreover,the use of traditional com-puted tomography(CT)two-dimensional(2D)images to recon-struct the tissue and organs requires exp... The anatomy of the human liver is complex,and the vascular system is highly variable.Moreover,the use of traditional com-puted tomography(CT)two-dimensional(2D)images to recon-struct the tissue and organs requires experienced doctors and lim-its the sharing and discussion of therapeutic plans[1]. 展开更多
关键词 liver surgery three dimensional printing vascular system sharing discussion therapeutic plans therapeutic plans computed tomography
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Three-Dimensional van Hove Singularities and Charge Density Wave Evolution in Kagome Lattice KV_(3)Sb_(5)
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作者 Yu Huang Haiyang Ma +13 位作者 Wei Xia Zhicheng Jiang Wenchuan Jing Xiangqi Liu Jiayu Liu Yuming Shi Xun Ma Runfeng Zhang Jin-Feng Jia Jishan Liu Mao Ye Zhengtai Liu Yanfeng Guo Dawei Shen 《Chinese Physics Letters》 2025年第12期226-238,共13页
The kagome metals AV_(3)Sb_(5)(A=K,Rb,Cs)feature intertwined Dirac fermions,topological flat bands,and van Hove singularities(vHS)near the Fermi level,which give rise to a range of exotic,strongly correlated phenomena... The kagome metals AV_(3)Sb_(5)(A=K,Rb,Cs)feature intertwined Dirac fermions,topological flat bands,and van Hove singularities(vHS)near the Fermi level,which give rise to a range of exotic,strongly correlated phenomena such as charge density waves(CDW)and superconductivity.Although the vHS from V 3d states have been implicated in CDW formation,their three-dimensional nature and temperature evolution remain poorly understood.In this study,we used high-resolution angle-resolved photoemission spectroscopy and density functional theory to reveal pronounced out-of-plane dispersion of vHS and their temperature dependence in KV_(3)Sb_(5).The identified c-axis band folding and scattering channels were directly linked to the CDW order.These results demonstrate that the CDW transition in this family involves cooperative coupling between electron correlations and structural modulation along the c axis.This offers new insights into the interplay of topology,correlations,and lattice instabilities in kagome metals. 展开更多
关键词 kagome metals dirac fermionstopological flat bandsand van hove singularities vhs near charge density waves cdw three dimensional van hove singularities kv sb c axis band folding charge density wave evolution
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Corrigendum to“Deep transfer learning for three-dimensional aerodynamic pressure prediction under data scarcity”[Theor.App.Mech.Lett.15(2025)100571]
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作者 Hao Zhang Yang Shen +2 位作者 Wei Huang Zan Xie Yao-bin Niu 《Theoretical & Applied Mechanics Letters》 2025年第6期630-630,共1页
The authors regret the following two errors.
关键词 deep transfer learning data scarcity three dimensional aerodynamic pressure prediction
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Preparation of three-dimensional interconnected mesoporous anatase TiO_2-SiO_2 nanocomposites with high photocatalytic activities 被引量:4
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作者 董维阳 姚有为 +2 位作者 孙尧俊 华伟明 庄国顺 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第6期846-854,共9页
In this article, we report the preparation of a three-dimensional(3D) interconnected mesoporous anatase TiO2-SiO2 nanocomposite. The nanocomposite was obtained by using an ordered two-dimensional(2D) hexagonal mes... In this article, we report the preparation of a three-dimensional(3D) interconnected mesoporous anatase TiO2-SiO2 nanocomposite. The nanocomposite was obtained by using an ordered two-dimensional(2D) hexagonal mesoporous anatase 70 TiO2-30 SiO2-950 nanocomposite(crystallized at 950 °C for 2 h) as a precursor, NaO H as an etchant of SiO2 via a "creating mesopores in the pore walls" approach. Our strategy adopts mild conditions of creating pores such as diluted NaO H solution, appropriate temperature and solid/liquid ratio, etc. aiming at ensuring the integrities of mesopores architecture and anatase nanocrystals. XRD, TEM and N2 sorption techniques have been used to systematically investigate the physico-chemical properties of the nanocomposites. The results show that the intrawall mesopores are highly dense and uniform(average pore size 3.6 nm), and highly link the initial mesochannels in a 3D manner while retaining mesostructural integrity. There is no significant change to either crystallinity or size of the anatase nanocrystals before and after creating the intrawall mesopores. The photocatalytic degradation rates of rhodamine B(RhB, 0.303 min^–1) and methylene blue(MB, 0.757 min^–1) dyes on the resultant nanocomposite are very high, which are 5.1 and 5.3 times that of the precursor; even up to 16.5 and 24.1 times that of Degussa P25 photocatalyst, respectively. These results clearly demonstrate that the 3D interconnected mesopores structure plays an overwhelming role to the increments of activities. The 3D mesoporous anatase TiO2-SiO2 nanocomposite exhibits unexpected-high degradation activities to RhB and MB in the mesoporous metal oxide-based materials reported so far. Additionally, the nanocomposite is considerably stable and reusable. We believe that this method would pave the way for the preparation of other 3D highly interconnected mesoporous metal oxide-based materials with ultra-high performance. 展开更多
关键词 PREPARATION Mesoporous anatase crystal-silica nanocomposite three dimensional interconnected mesopores architecture Photocatalytic degradation Organic pollutants
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Spectroscopic Studies of a Three-dimensional, Five-coordinated Copper(Ⅱ) Complex via Hydrogen Bonds: [Cu(PDA)(H_2O)_2](H_2PDA=Pyridine-2,6-dicarboxylic Acid)
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作者 WANG Wen-zhen +2 位作者 JIANG Zong-hui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第1期6-9,共4页
A new copper(Ⅱ) complex [Cu(PDA)(H 2O) 2] was synthesized and its structure was determined. Cu(Ⅱ) is five coordinated in a tetragonal pyramid geometry. The two coordinating water molecules are different and t... A new copper(Ⅱ) complex [Cu(PDA)(H 2O) 2] was synthesized and its structure was determined. Cu(Ⅱ) is five coordinated in a tetragonal pyramid geometry. The two coordinating water molecules are different and the two Cu-O bond lengths differ by nearly 0.02 nm. The whole crystal is linked to form a three dimensional network by means of hydrogen bonds. The X band ESR spectrum shows three different g tensors with a well resolved hyperfine structure in the g z signal, giving the ESR parameters g x=2 05, g y =2 065 and g z =2 29. The covalency of the coordinate bonds and the deviation from tetragonal pyramid geometry for the complex are discussed based on the ESR spectra. 展开更多
关键词 Crystal structure three dimensional network ESR spectrum Tetragonal pyramid geometry Hydrogen bond π π interaction
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Three-Dimensional Ultrasonography in Obstetrics:the Clinical Value
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作者 徐辉雄 张青萍 +4 位作者 肖先桃 周玉清 闻良珍 许建平 蔡敏 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2001年第1期38-41,47,共5页
To investigate the clinical value of three dimensional ultrasonography (3DUS) in obstetrics, various 3DUS rendering methods including surface mode, transparent mode and multiplanar mode were employed to scan 30 fetus... To investigate the clinical value of three dimensional ultrasonography (3DUS) in obstetrics, various 3DUS rendering methods including surface mode, transparent mode and multiplanar mode were employed to scan 30 fetuses in second and third trimester by using the transabdominal volume transducer. The results showed that surface mode could vividly demonstrate the surface morphologic features of the fetuses, as well as the stereo shape and the spatial relationship among the surface structures. The face, limbs, umbilical cord and outer genitalia of the fetus could be well displayed by surface mode. Transparent mode could reveal the bony structures under the surface, such as ribs, vertebrae, crania, etc. The result was not affected by the sophisticated curvature of these bony structures and the success rate was up to 100 %. When rendered by multiplanar mode, the region of interest (ROI) could be viewed from different directions. It should be concluded that 3DUS could serve as a supplement to two dimensional ultrasonography (2DUS). 3DUS might play an important role in prenatal diagnosis and enhance the diagnostic confidence level of the physicians. 展开更多
关键词 three dimensional ultrasonography FETUS OBSTETRICS prenatal diagnosis
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Characteristics of the ThreeDimensional Fluorescence Spectra of Fossil Fuels
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作者 YONG Ke lan (School of Life Sciences, Shanghai University) L Jing ci (School of Chemistry and Chemical Engineering, Shanghai University) 《Advances in Manufacturing》 SCIE CAS 1999年第4期321-324,共4页
We have found some fluorescence characteristics of fossil fuels based on the contour maps of the three dimensional fluorescence spectra of their non quenching samples. The common fluorescence characteristic is t... We have found some fluorescence characteristics of fossil fuels based on the contour maps of the three dimensional fluorescence spectra of their non quenching samples. The common fluorescence characteristic is that the main peaks of various fossil fuels are located in the vicinity of excitation/emission wavelength pair 228nm/340nm.The diversity of fluorescence characteristics can be represented with several indexes α,K,F and R ,and these indexes provide measurable parameters for division of fluorescence fingerprints of fossil fuels. The fluorescence fingerprints of fossil fuels can be divided into five models named O,B,Q,P and G that are corresponding to condensate oil, light oil, heavy oil, coal and natural gas, respectively. The technique has a potential application in study of environment pollution on crude oil and geochemical exploration of fossil fuels. 展开更多
关键词 three dimensional fluorescence spectra fossil fuel FINGERPRINT
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Review of Electronic Speckle Pattern Interferometry(ESPI) for Three Dimensional Displacement Measurement 被引量:24
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作者 YANG Lianxiang XIE Xin +2 位作者 ZHU Lianqing WU Sijin WANG Yonghong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第1期1-13,共13页
Three dimensional(3D) displacements, which can be translated further into 3D strain, are key parameters tor design, manufacturing and quality control. Using different optical setups, phase-shift methods, and algorit... Three dimensional(3D) displacements, which can be translated further into 3D strain, are key parameters tor design, manufacturing and quality control. Using different optical setups, phase-shift methods, and algorithms, several different 3D electronic speckle pattern interferometry(ESPl) systems for displacement and strain measurements have been achieved and commercialized. This paper provides a review of the recent developments in ESPI systems for 3D displacement and strain measurement. After an overview of the fundamentals of ESP! theory, temporal phase-shift, and spatial phase-shift techniques, 3D deformation measurements by the temporal phase-shift ESPI system, which is suited well for static measurement, and by the spatial phase-shift ESPI system, which is particularly useful for dynamic measurement, are discussed. For each method, the basic theory, a brief derivation and different optical layouts are presented. The state of art application, potential and limitation of the ESPI systems are shown and demonstrated. 展开更多
关键词 electronic speckle pattern interferometry(ESPI) three dimensional displacement and strain measurement static loading dynamic loading phase-shift technology
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THREE DIMENSIONAL NONLINEAR NUMERICAL MODEL WITH INCLINED PRESSURE FOR SALTWATER INTRUSION AT THE YANGTZE RIVER ESTUARY 被引量:10
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作者 Zhu, Yuliang Zheng, Jinhai +1 位作者 Mao, Lihua Yan, Yixin 《Journal of Hydrodynamics》 SCIE EI CSCD 2000年第1期57-66,共10页
A three-dimensional nonlinear numerical model with inclined pressure was developed to compute the saltwater intrusion at the Yangtze River Estuary. The σ-transformation was introduced in the vertical plane to achieve... A three-dimensional nonlinear numerical model with inclined pressure was developed to compute the saltwater intrusion at the Yangtze River Estuary. The σ-transformation was introduced in the vertical plane to achieve the same lattices in the whole domain of interest. The mode-splitting technique can be used to split the three-dimensional governing equations into the surface gravity waves (external mode) and the internal gravity waves (internal mode). And the external mode was solved by the improved double-sweep-implicit (DSI) finite difference method and the internal mode was solved by the Eulerian-Lagrangian method. The Eulerian-Lagrangian method can not only reduce the numerical diffusion but also increase the computational accuracy through the improvement of the finite difference scheme in the vertical direction. The application of the model to the Yangtze River Estuary was carried out for the calculation of the saltwater intrusion and the null point. Results of the temporal and spatial distribution of the flow velocity and the salinity coincide with the measured data quite well. The formation and location of the underwater sandbars in the North Channel of the Yangtze River Estuary are closely related to the local salinity, the null point, the predominant current and the residual flow. 展开更多
关键词 Flow of water Mathematical models Percolation (fluids) Seawater three dimensional
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Accuracy of three-dimensional seismic ground response analysis in time domain using nonlinear numerical simulations 被引量:7
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作者 Liang Fayun Chen Haibing Huang Maosong 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2017年第3期487-498,共12页
To provide appropriate uses of nonlinear ground response analysis for engineering practice, a three-dimensional soil column with a distributed mass system and a time domain numerical analysis were implemented on the O... To provide appropriate uses of nonlinear ground response analysis for engineering practice, a three-dimensional soil column with a distributed mass system and a time domain numerical analysis were implemented on the Open Sees simulation platform. The standard mesh of a three-dimensional soil column was suggested to be satisfied with the specified maximum frequency. The layered soil column was divided into multiple sub-soils with a different viscous damping matrix according to the shear velocities as the soil properties were significantly different. It was necessary to use a combination of other one-dimensional or three-dimensional nonlinear seismic ground analysis programs to confirm the applicability of nonlinear seismic ground motion response analysis procedures in soft soil or for strong earthquakes. The accuracy of the three-dimensional soil column finite element method was verified by dynamic centrifuge model testing under different peak accelerations of the earthquake. As a result, nonlinear seismic ground motion response analysis procedures were improved in this study. The accuracy and efficiency of the three-dimensional seismic ground response analysis can be adapted to the requirements of engineering practice. 展开更多
关键词 three dimensional soil column seismic ground response centrifugal model test nonlinear analysis accuracyverification
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Effect of three dimensional stress state on unstable fracture condition and crack opening level in a new crack growth model 被引量:7
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作者 Fang WANG Weicheng CUI 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2010年第1期41-49,共9页
A new model for the analysis of fatigue crack growth in the metal structures was proposed. This model shows a promising capability of explaining various fatigue phenomena. The new crack growth model is further complet... A new model for the analysis of fatigue crack growth in the metal structures was proposed. This model shows a promising capability of explaining various fatigue phenomena. The new crack growth model is further completed by a continuous empirical formula for estimating the value of variable fracture toughness during crack propagation and a modified continuous equation for the crack tip stress/strain constraint factor used to calculate the stress intensity factor at the opening level. The prediction results are proved to agree well with the observed phenomena in test. 展开更多
关键词 Marine structures Crack growth rate three dimensional stress state Fracture toughness Crack tip stress/strain constraint factor
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THREE-DIMENSIONAL CHARACTERISTICS AND HOMOGENIZATION OF ELECTROMAGNETIC FIELD IN SOFT-CONTACT CONTINUOUS CASTING MOLD 被引量:5
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作者 A. Y. Deng, G.L. Jia and J.C. He (Key Laboratory for Electromagnetic Processing of Materials, Ministry of Education, Northeastern University, Shenyang 110004, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2001年第2期137-142,共6页
The three-dimensional electromagnetic characteristics and non-uniform distribution of electromagnetic field in soft-contact continuous casting mold have been analyzed by numerical simulation. The results show that the... The three-dimensional electromagnetic characteristics and non-uniform distribution of electromagnetic field in soft-contact continuous casting mold have been analyzed by numerical simulation. The results show that the maximum electromagnetic flux density is found in front of slit; the electromagnetic flux density becomes large as the coil current and slit number increase. In a certain frequency range, the electromagnetic flux density increases with the increase of frequency and the frequency range is different with the change of azimuthal position along the inner wall of mold. The uniformity of electromagnetic field is influenced mainly by frequency and mold structure parameters. Increasing slit number and adjusting slit arrangement position can improve the electromagnetic flux density and the uniformity of electromagnetic field. For a soft-contact mold with 16 slits, when frequency is 20 kHz, the optimal slit arrangement parameter is a:b=1:2, c=0. 展开更多
关键词 Computer simulation Electromagnetic fields Magnetic properties MOLDS Optimization three dimensional
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Three dimensional tectonic stress field in North China 被引量:6
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作者 陈连旺 陆远忠 +2 位作者 张杰 许桂林 郭若眉 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第2期155-164,共10页
According to the latest data of geological structure, geophysics, in-situ stress measurement and focal mechanism,3-D tectonic stress field model in North China is built and 3-D tectonic stress field pattern of North C... According to the latest data of geological structure, geophysics, in-situ stress measurement and focal mechanism,3-D tectonic stress field model in North China is built and 3-D tectonic stress field pattern of North China aresimulated by finite element method. Then the overall characteristics and regional specific feature of North Chinaare studied. Finally, the influences of the valid dynamic boundary conditions of North China Block, active faultsand the inhomogeneity of crustal medium on tectonic stress field of North China are investigated. 展开更多
关键词 North China tectonic stress field three dimensional pattern numerical simulation by finite element method
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Three-dimensional graphitic carbon sphere foams as sorbents for cleaning oil spills 被引量:5
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作者 Saisai Li Haijun Zhang +2 位作者 Longhao Dong Haipeng Liu Quanli Jia 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第3期513-520,共8页
Frequent offshore oil spill accidents, industrial oily sewage, and the indiscriminate disposal of urban oily sewage have caused seri- ous impacts on the human living environment and health. The traditional oil-water s... Frequent offshore oil spill accidents, industrial oily sewage, and the indiscriminate disposal of urban oily sewage have caused seri- ous impacts on the human living environment and health. The traditional oil-water separation methods not only cause easily environmental secondary pollution but also a waste of limited resources. Therefore, in this work, three-dimensional (3D) graphitic carbon sphere (GCS) foams (collectively referred hereafter as 3D foams) with a 3D porous structure, pore size distribution of 25-200 μm, and high porosity of 62vol% were prepared for oil adsorption via gel casting using GCS as the starting materials. The results indicate that the water contact angle (WCA) of the as-prepared 3D foams is 130°. The contents of GCS greatly influenced the hydrophobicity, WCA, and microstructure of the as-prepared samples. The adsorption capacities of the as-prepared 3D foams for paraffin oil, vegetable oil, and vacuum pump oil were approximately 12-15 g/g, which were 10 times that of GCS powder. The as-prepared foams are desirable characteristics of a good sorbent and could be widely used in oil spill accidents. 展开更多
关键词 graphitic carbon spheres three dimensional FOAMS gel casting oil adsorption
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Three-Dimensional TIN Algorithm for Digital Terrain Modeling 被引量:7
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作者 ZHU Qing ZHANG Yeting LI Fengchun 《Geo-Spatial Information Science》 2008年第2期79-85,共7页
The problem of taking an unorganized point cloud in 3D space and fitting a polyhedral surface to those points is both important and difficult. Aiming at increasing applications of full three dimensional digital terrai... The problem of taking an unorganized point cloud in 3D space and fitting a polyhedral surface to those points is both important and difficult. Aiming at increasing applications of full three dimensional digital terrain surface modeling, a new algorithm for the automatic generation of three dimensional triangulated irregular network from a point cloud is pro- posed. Based on the local topological consistency test, a combined algorithm of constrained 3D Delaunay triangulation and region-growing is extended to ensure topologically correct reconstruction. This paper also introduced an efficient neighbor- ing triangle location method by making full use of the surface normal information. Experimental results prove that this algo- rithm can efficiently obtain the most reasonable reconstructed mesh surface with arbitrary topology, wherein the automati- cally reconstructed surface has only small topological difference from the true surface. This algorithm has potential applica- tions to virtual environments, computer vision, and so on. 展开更多
关键词 three dimensional triangulated irregular network digital terrain surface modeling Delaunay triangulation
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