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Ipsilateral proximal and distal radius fractures with unstable elbow joint: Which should we address first?
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作者 Nur Azuatul Akma Kamaludin Nur Azree Ferdaus Kamudin +1 位作者 Shalimar Abdullah Jamari Sapuan 《中华创伤杂志:英文版》 CAS CSCD 2019年第1期59-62,共4页
Simultaneous ipsilateral fractures involving radial head and distal end of radius are uncommon. We present our thoughts on which fracture should be addressed first. A 68-year-old lady sustained an ipsilateral fracture... Simultaneous ipsilateral fractures involving radial head and distal end of radius are uncommon. We present our thoughts on which fracture should be addressed first. A 68-year-old lady sustained an ipsilateral fracture of the right radial head and distal end of radius following a fall. Clinically her right elbow was posteriorly dislocated and right wrist was deformed. Plain radiographs showed an intraarticular fracture of the distal end of radius and a comminution radial head fracture with a proximally migrated radius. Magnetic resonance imaging (MRI) showed no significant ligament injuries. We addressed her distal radius first with an an atomical lock ing plate followed by her radial head with a radial head replacement. Our rationale to treat the distal end radius: first was to obtain a correct alignment of Lister's tubercle and correct the distal radius height. Lister's tubercle was used to guide for the correct rotation of the radial head prosthesis. Correcting the distal end fracture radial height helped us with length selection of the radial head prosthesis and address the proximally migrated radial shaft and neck. Postoperative radiographs showed an acceptable reduction. The Cooney score was 75 at 3 months postoperatively, which was equivalent to a fair functional outcome. 展开更多
关键词 Simultaneous IPSILATERAL FRACTURES Radius FRACTURES IRREDUCIBLE elbow dislocation RADIAL HEAD RADIAL HEAD ARTHROPLASTY
A meshless method by using radial basis function for numerical solutions of wave shoaling equation 预览
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作者 Lin-jian Wu Yuan-zhan Wang +1 位作者 Yi Li1 Chun-ning Ji 《水动力学研究与进展:英文版》 SCIE EI CSCD 2019年第1期83-92,共10页
In this present study,a numerical method is proposed for solving the wave shoaling differential equations with turbulent and laminar boundary layers by using the meshless method based on the radial basis function.The ... In this present study,a numerical method is proposed for solving the wave shoaling differential equations with turbulent and laminar boundary layers by using the meshless method based on the radial basis function.The numerical solutions are compared with those of the finite difference method to see the accuracy,the validity and the applicability of the methodology developed in this paper.The meshless method by using the radial basis function can effectively improve the computational efficiency.The findings in this paper provide a significant support for the study of wave shoaling problems. 展开更多
关键词 MESHLESS method RADIAL basis function wave SHOALING differential EQUATION
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桡动脉侧支穿支皮瓣在肘后皮肤严重缺损中的应用 预览
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作者 徐卿芯 崔光怀 +2 位作者 万蓁蓁 刘玉树 刘文明 《中国整形与重建外科(英文)》 2019年第1期14-17,共4页
exposed wound of deep tissue behind elbow. Methods From April 2016 to December 2018, 28 patients with posterior elbow skin and soft tissue defect with exposed bone and tendon were treated in our hospital. the radial c... exposed wound of deep tissue behind elbow. Methods From April 2016 to December 2018, 28 patients with posterior elbow skin and soft tissue defect with exposed bone and tendon were treated in our hospital. the radial collateral artery perforator flap was used to repair the wound. There were 19 cases of skin defect with ulna exposure after electric shock injury, 5 cases of hot compression injury and 4 cases of bone exposure caused by skin contusion after traffic accident. Results There is no complication after the operation, all the flaps were survived. The flaps had good quality and satisfactory recovery of appearance and function. Conclusion The lateral upper arm flap designed by perforating branch of radial collateral artery is an effective method for posterior elbow skin and soft tissue defect because of its constant anatomic position and long vascular pedicle. 展开更多
关键词 RADIAL COLLATERAL artery Soft tissue defects PERFORATOR FLAP T ransplantation
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RSBP15 interacts with and stabilizes dRSPH3 during sperm axoneme assembly in Drosophila
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作者 Ya Wang Rui Xu +11 位作者 Yiwei Cheng Haowei Cao Zibin Wang Tianyu Zhu Jiayin Jiang Hao Zhang Chang Wang Lin Qi Mingxi Liu Xuejiang Guo Juan Huang Jiahao Sha 《遗传学报:英文版》 SCIE CAS CSCD 2019年第6期281-290,共10页
Flagellum in sperm is composed of over 200 different proteins and is essential for sperm motility. In particular, defects in the assembly of the radial spoke in the flagellum result in male infertility due to loss of ... Flagellum in sperm is composed of over 200 different proteins and is essential for sperm motility. In particular, defects in the assembly of the radial spoke in the flagellum result in male infertility due to loss of sperm motility. However, mechanisms regulating radial spoke assembly remain unclear in metazoans.Here, we identified a novel Drosophila protein radial spoke binding protein 15(RSBP15) which plays an important role in regulating radial spoke assembly. Loss of RSBP15 results in complete lack of mature sperms in seminal vesicles(SVs), asynchronous individualization complex(IC) and defective "9 + 2"structure in flagella. RSBP15 is colocalized with dRSPH3 in sperm flagella, and interacts with dRSPH3 through its DD_R_PKA superfamily domain which is important for the stabilization of dRSPH3. Moreover,loss of dRSPH3, as well as dRSPH1, dRSPH4 a and dRSPH9, showed similar phenotypes to rsbp15 KO mutant. Together, our results suggest that RSBP15 acts in stabilizing the radial spoke protein complex to anchor and strengthen the radial spoke structures in sperm flagella. 展开更多
关键词 RSBP15 RSPH3 FLAGELLUM RADIAL SPOKE DROSOPHILA
Mass predictions of the relativistic continuum Hartree-Bogoliubov model with radial basis function approach
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作者 仕敏 牛中明 梁豪兆 《中国物理C:英文版》 SCIE CAS CSCD 2019年第7期53-60,共8页
The radial basis function(RBF) approach is a powerful tool to improve nuclear mass predictions. By combining the RBF approach with the latest relativistic continuum Hartree-Bogoliubov(RCHB) model, the local systematic... The radial basis function(RBF) approach is a powerful tool to improve nuclear mass predictions. By combining the RBF approach with the latest relativistic continuum Hartree-Bogoliubov(RCHB) model, the local systematic deviations between the RCHB mass predictions and the experimental data are eliminated, and the root-meansquare(rms) mass deviation is significantly reduced from 7.923 MeV to 0.386 MeV. However, systematic deviations between the RBF improved mass predictions and the experimental data remain for nuclei with four different odd-even parities, i.e.(even Z, even N),(even Z, odd N),(odd Z, even N), and(odd Z, odd N). They can be reduced by separately training RBF for the four groups of nuclei, and the resulting rms deviation decreases to 0.229 MeV. It is found that the RBF approach can describe the deformation effects neglected in the present RCHB mass calculations, and also improves the description of the shell effect and the pairing effect. 展开更多
关键词 nuclear MASSES RADIAL basis function APPROACH RELATIVISTIC CONTINUUM Hartree-Bogoliubov MODEL
Determining the IgG concentrations in bovine colostrum and calf sera with a novel enzymatic assay 预览
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作者 M.Drikic C.Windeyer +3 位作者 S.Olsen Y.Fu L.Doepel J.De Buck 《畜牧与生物技术杂志:英文版》 SCIE CAS CSCD 2019年第1期239-247,共9页
Background: Immune protection in newborn calves relies on a combination of the timing,volume and quality of colostrum consumed by the calf after birth.Poor quality colostrum with inadequate immunoglobulin concentratio... Background: Immune protection in newborn calves relies on a combination of the timing,volume and quality of colostrum consumed by the calf after birth.Poor quality colostrum with inadequate immunoglobulin concentration contributes to failed transfer of passive immunity in calves,leading to higher calf morbidity and mortality.Therefore,estimating colostrum quality and ensuring the transfer of passive immunity on farm is of critical importance.Currently,there are no on-farm tools that directly measure immunoglobulin content in colostrum or serum.The aim of this study was to apply a novel molecular assay,split trehalase immunoglobulin G assay(STIGA),to directly estimate immunoglobulin content in dairy and beef colostrum and calf sera,and to examine its potential to be developed as on-farm test.The STIGA is based on a split version of trehalase TreA,an enzyme that converts trehalose into glucose,enabling the use of a common glucometer for signal detection.In a first study,60 dairy and64 beef colostrum and 83 dairy and 84 beef calf sera samples were tested with STIGA,and the resulting glucose production was measured and compared with radial immunodiffusion,the standard method for measuring immunoglobulin concentrations.Results: Pearson correlation coefficients between the methods were determined and the sensitivity,specificity,and accuracy of the test were calculated for different colostrum quality and failed transfer of passive immunity cut-off points.The correlations of the STIGA measured by colorimetric enzymatic reaction compared to radial immunodiffusion for dairy and beef colostrum were 0.72 and 0.73,respectively,whereas the correlations for dairy and beef sera were 0.9 and 0.85,respectively.Next,STIGA was tested in a blinded study with fresh colostrum and serum samples where the correlation coefficient was 0.93 and 0.94,respectively.Furthermore,the performance of STIGA followed by glucometer readings resulted in correlations with radial immunodiffusion of 0.7 and 0.85 for dairy and beef colostrum and 0.94 and 0 展开更多
关键词 CATTLE COLOSTRUM IMMUNOGLOBULINS Passive immunity Radial immunodiffusion Split TREHALASE
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Radial Operators on the Weighted Bergman Spaces over the Polydisk
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作者 Ran LI Yu Feng LU 《数学学报:英文版》 SCIE CSCD 2019年第2期227-238,共12页
In this paper, we study radial operators in Toeplitz algebra on the weighted Bergman spaces over the polydisk by the(m, λ)-Berezin transform and find that a radial operator can be approximated in norm by Toeplitz ope... In this paper, we study radial operators in Toeplitz algebra on the weighted Bergman spaces over the polydisk by the(m, λ)-Berezin transform and find that a radial operator can be approximated in norm by Toeplitz operators without any conditions. We prove that the compactness of a radial operator is equivalent to the property of vanishing of its(0, λ)-Berezin transform on the boundary. In addition, we show that an operator S is radial if and only if its(m, λ)-Berezin transform is a separately radial function. 展开更多
关键词 RADIAL OPERATORS (m λ)-Berezin transform weighted BERGMAN SPACES TOEPLITZ OPERATORS
Modeling and robust adaptive control for a coaxial twelve-rotor UAV 预览
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作者 裴信彪 Peng Cheng +2 位作者 Bai Yue Wu Helong Ma Ping 《高技术通讯:英文版》 CAS 2019年第2期137-143,共7页
Compared with the quad-rotor unmanned aerial vehicle (UAV), the coaxial twelve-rotor UAV has stronger load carrying capacity, higher driving ability and stronger damage resistance. This paper focuses on its robust ada... Compared with the quad-rotor unmanned aerial vehicle (UAV), the coaxial twelve-rotor UAV has stronger load carrying capacity, higher driving ability and stronger damage resistance. This paper focuses on its robust adaptive control. First, a mathematical model of a coaxial twelve-rotor is established. Aiming at the problem of model uncertainty and external disturbance of the coaxial twelve-rotor UAV, the attitude controller is innovatively adopted with the combination of a backstepping sliding mode controller (BSMC) and an adaptive radial basis function neural network (RBFNN). The BSMC combines the advantages of backstepping control and sliding mode control, which has a simple design process and strong robustness. The RBFNN as an uncertain observer, can effectively estimate the total uncertainty. Then the stability of the twelve-rotor UAV control system is proved by Lyapunov stability theorem. Finally, it is proved that the robust adaptive control strategy presented in this paper can overcome model uncertainty and external disturbance effectively through numerical simulation and prototype of twelve-rotor UAV tests. 展开更多
关键词 COAXIAL twelve-rotor unmanned aerial vehicle (UAV) backstepping sliding mode controller (BSMC) adaptive radial basis function neural network (RBFNN) external disturbances
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Health diagnosis of concrete dams using hybrid FWA with RBF-based surrogate model 预览
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作者 Si-qi Dou Jun-jie Li Fei Kang 《水科学与水工程:英文版》 EI CAS CSCD 2019年第3期188-195,共8页
Structural health monitoring is important to ensuring the health and safety of dams.An inverse analysis method based on a novel hybrid fireworks algorithm (FWA) and the radial basis function (RBF) model is proposed to... Structural health monitoring is important to ensuring the health and safety of dams.An inverse analysis method based on a novel hybrid fireworks algorithm (FWA) and the radial basis function (RBF) model is proposed to diagnose the health condition of concrete dams.The damage of concrete dams is diagnosed by identifying the elastic modulus of materials using the displacement changes at different reservoir water levels.FWA is a global optimization intelligent algorithm.The proposed hybrid algorithm combines the FWA with the pattern search algorithm, which has a high capability for local optimization.Examples of benchmark functions and pseudo-experiment examples of concrete dams illustrate that the hybrid FWA improves the convergence speed and robustness of the original algorithm.To address the time consumption problem, an RBF-based surrogate model was established to replace part of the finite element method in inverse analysis.Numerical examples of concrete dams illustrate that the use of an RBF-based surrogate model significantly reduces the computation time of inverse analysis with little influence on identification accuracy.The presented hybrid FWA combined with the RBF network can quickly and accurately determine the elastic modulus of materials, and then determine the health status of the concrete dam. 展开更多
关键词 FIREWORKS algorithm(FWA) RADIAL BASIS function (RBF) network Surrogate model INVERSE analysis Structural HEALTH monitoring
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Neutronic analysis of ITER radial x-ray camera
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作者 牛璐莹 曹宏睿 +1 位作者 徐坤 胡立群 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第2期105-112,共8页
The radial x-ray camera(RXC) is designed to measure the poloidal profile of plasma x-ray emission with high spatial and temporal resolution. The RXC diagnostic system consists of internal camera module and external ca... The radial x-ray camera(RXC) is designed to measure the poloidal profile of plasma x-ray emission with high spatial and temporal resolution. The RXC diagnostic system consists of internal camera module and external camera module that view the core region and outer region through the vertical slots of the diagnostic first wall and diagnostics shield module of the equatorial port plug. To ensure the normal performance of the silicon photodiode array detectors of the cameras in the hard neutron irradiation environment in ITER tokamak, it is necessary to calculate neutron flux, radiation damage and the nuclear heating of the silicon photodiode array detectors and simulate the radiation maps of the range of RXC. This work estimated the nuclear environment of RXC based on Monte Carlo N-particle transport code, plasma scenarios of ITER tokamak and the RXC-integrated ITER CLITE model. The neutron flux of silicon photodiode array detectors and the lifetime of the silicon photodiode detector in the camera were calculated. The neutronic analysis results show that the shielding design has achieved the effect as expected and is able to guarantee the normal work of the detector during the ITER deuterium–deuterium phase without replacement, three detectors of the external camera can be operated during the whole deuterium–tritium phase without replacement. 展开更多
关键词 TOKAMAK RADIAL X-RAY CAMERA NEUTRONIC
Radial extracorporeal shock wave promotes the enhanced permeability and retention effect to reinforce cancer nanothermotherapeutics
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作者 Chunyang Yin Shunhao Wang +4 位作者 Quanzhong Ren Xinming Shen Xiaodong Chen Yajun Liu Sijin Liu 《科学通报:英文版》 SCIE EI CSCD 2019年第10期679-689,共11页
Since most cancer nanomedicine relies on the enhanced permeability and retention (EPR) effect to eradicate tumors, strategies that are able to promote nanoparticle (NP) delivery and extravasation are presupposed to el... Since most cancer nanomedicine relies on the enhanced permeability and retention (EPR) effect to eradicate tumors, strategies that are able to promote nanoparticle (NP) delivery and extravasation are presupposed to elevate the EPR effect for more effective cancer therapeutics. However, nanothermotherapeutics still suffers from limited drug delivery into tumor sites, for even though numerous efforts have been made to enhance the selective tumor targeting of NPs. In this study, we uncovered that radial extracorporeal shock wave therapy (rESWT), an important approach in physical therapy that has been overlooked in cancer treatment in the past, can largely improve the EPR-dependent tumor uptake of NPs. We here defined the optimal low dosage and desirable combinatory manner for rESWT in driving NP accumulation towards tumors. Two underlying biophysical mechanisms responsible for the rESWT-enhanced EPR effect were proposed. On one hand, rESWT-conducted compressive and tensile forces could relieve high intra-tumoral pressure;on the other hand, rESWT-induced cavitation bubbles could directly distend and disrupt tumor blood vessels. All these together synergistically promoted vessel vasodilation, tumor perfusion and NP extravasation. Further experiments revealed that the combinatory therapeutics between rESWT and nanothermotherapeutics greatly improved the tumor-killing efficacy. Thus, our findings open a new path to improve EPR-mediated drug delivery w让h the assistance of rESWT. 展开更多
关键词 RADIAL EXTRACORPOREAL shock wave NANOMEDICINE Nanothermotherapeutics VASODILATION Tumor PERFUSION
Interior non-uniformity of acoustically excited oscillating gas bubbles 预览
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作者 Yu-ning Zhang Xiao-fei Li Zhong-yu Guo 《水动力学研究与进展:英文版》 SCIE EI CSCD 2019年第4期725-732,共8页
In the present paper, the interior non-uniformity of oscillating gas bubbles in liquids under an acoustic field is theoretically investigated, as well as the temperature non-uniformity in the surrounding liquid. The p... In the present paper, the interior non-uniformity of oscillating gas bubbles in liquids under an acoustic field is theoretically investigated, as well as the temperature non-uniformity in the surrounding liquid. The pressure, the density and the temperature inside the gas bubbles are quantitatively predicted for a wide range of bubble Mach numbers. It is shown that the bubble interior non-uniformity increases significantly with the increase of the bubble Mach number. In the case of a large Mach number, the values of aforementioned paramount parameters at the bubble center are significantly larger than those at the bubble interface. Except for a very thin layer close to the bubble interface, the effects of the temperature non-uniformity in the bulk liquid could be safely ignored. 展开更多
关键词 CAVITATION gas BUBBLES acoustic field radial oscillation NON-UNIFORMITY MACH number
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Atomic Structure of Cu49Hf42Al9 Metallic Glass with High Glass-Forming Ability and Plasticity
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作者 Kai Li Yu-Jen Chou +1 位作者 Fang-Liang Gao Guo-Qiang Li 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第7期803-807,共5页
Electron diffraction was used to study the local atomic structure of Cu49Hf42Al9 metallic glasses (MGs). The amorphous nature of the MG was fully retained after the compression test. The partial radial distribution fu... Electron diffraction was used to study the local atomic structure of Cu49Hf42Al9 metallic glasses (MGs). The amorphous nature of the MG was fully retained after the compression test. The partial radial distribution functions (PRDFs) of the MG structure obtained from the atomic model using reverse Monte Carlo and density functional theory optimization display that the peaks of the first nearest-neighbour distances for Cu-Cu, Hf-Cu and Hf-Hf atomic pairs were located at 2.56 A, 2.78 A and 3.23 A, respectively. The wide distribution of PRDF for Hf-Hf atomic pair explained the high plasticity of the material. 展开更多
关键词 METALLIC glass RADIAL distribution function Electron DIFFRACTION Density functional theory ATOMIC structure
Endoscopic identification of endoluminal esophageal landmarks for radial and longitudinal orientation and lesion location 预览
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作者 Fabian Emura Rene Gomez-Esquivel +4 位作者 Carlos Rodriguez-Reyes Petros Benias Javier Preciado Michael Wallace Luis Giraldo-Cadavid 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第4期498-508,共11页
AIM To characterize esophageal endoluminal landmarks to permit radial and longitudinal esophageal orientation and accurate lesion location.METHODS Distance from the incisors and radial orientation were estimated for t... AIM To characterize esophageal endoluminal landmarks to permit radial and longitudinal esophageal orientation and accurate lesion location.METHODS Distance from the incisors and radial orientation were estimated for the main left bronchus and the left atrium landmarks in 207 consecutive patients using white light examination.A sub-study was also performed using white light followed by endoscopic ultrasound(EUS)in 25 consecutive patients to confirm the findings.The scope orientation throughout the exam was maintained at the natural axis,where the left esophageal quadrant corresponds to the area between 6 and 9 o'clock.When an anatomical landmark was identified,it was recorded with a photograph and its quadrant orientation and distance from the incisors were determined.The reference points to obtain the distances and radial orientation were as follows:the midpoint of the left main bronchus and the most intense pulsatile zone of the left atrium.With the video processor system set to moderate insufflation,measurements were obtained at the end of the patients'air expiration.RESULTS The left main bronchus and left atrium esophageal landmarks were identified using white light in 99%and 100%of subjects at a mean distance of 25.8 cm(SD 2.3),and 31.4 cm(SD 2.4)from the incisors,respectively.The left main bronchus landmark was found to be a tubular,concave,non-pulsatile,esophageal external compression,occupying approximately 1/4 of the circumference.The left atrium landmark was identified as a round,convex,pulsatile,esophageal external compression,occupying approximately 1/4 of the circumference.Both landmarks were identified using white light on the anterior esophageal quadrant.In the substudy,the left main bronchus was identified in 24(92%)patients at 25.4 cm(SD 2.1)and 26.7 cm(SD 1.9)from the incisors,by white light and EUS,respectively.The left atrium was recognized in all patients at 30.5 cm(SD 1.9),and 31.6 cm(SD 2.3)from the incisors,by both white light and EUS,respectively.EUS confirmed that the landmarks correspond 展开更多
关键词 Esophagus Natural landmark RADIAL ORIENTATION Longitudinal ORIENTATION Four-quadrants LEFT main BRONCHUS LEFT atrium
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Ambient noise Love wave tomography of China 预览
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作者 ZhiGao Yang XiaoDong Song 《地球与行星物理:英文版》 CSCD 2019年第3期218-231,共14页
We first report on the Love wave tomography of China based on ambient noise cross-correlations. We used 3 years of continuous waveform data recorded by 206 broadband seismic stations on the Chinese Mainland and 36 nei... We first report on the Love wave tomography of China based on ambient noise cross-correlations. We used 3 years of continuous waveform data recorded by 206 broadband seismic stations on the Chinese Mainland and 36 neighboring global stations and obtained Love wave empirical Green’s functions from cross-correlations of the horizontal components. The Love wave group velocity dispersion measurements were used to construct dispersion maps of 8-to 40-s periods, which were then inverted to obtain a threedimensional horizontally polarized S-wave(SH) velocity structure. The resolution was approximately 4°× 4° and 8°× 8° for eastern and western China, respectively, and extended to a depth of approximately 50 km. The SH model was generally consistent with a previously published vertically polarized S-wave(SV) model and showed large-scale features that were consistent with geological units, such as the major basins and changes in the crustal thickness across the north-south gravity lineament. The SH and SV models also showed substantial differences, which were used to examine the subsurface radial anisotropy. We define the radial anisotropy parameter asψ = 2(VSH-VSV)/(VSH+ VSV). At a shallow depth, we observed significant radial anisotropy under major basins, which may be related to thick sedimentary layers. At the mid to lower crust, most of the Chinese continent showed strong positive radial anisotropy(SH > SV).Central and southern Tibet showed strong positive anisotropy, whereas the radial anisotropy was relatively weak at the northern and eastern margins, which suggests a change in deformation style from the plateau interior to its margins. The North China craton showed prominent positive radial anisotropy, which may be related to decratonization and strong extension since the Mesozoic Era. Love waves are less well retrieved than Rayleigh waves from ambient noise cross-correlations. Increasing the duration of the cross-correlation data beyond 4 to 8 years may not aid in retrieving Love waves of longer periods, 展开更多
关键词 AMBIENT noise TOMOGRAPHY LOVE WAVE RADIAL ANISOTROPY China
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热采井井筒环形空间温度场分布研究 预览
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作者 苏雪茹 丁银川 《云南化工》 CAS 2019年第8期71-72,共2页
在稠油热采过程中,必然产生温度场在井筒内传递问题,了解温度场分布等情况对采油周期、出油量、出油质量、套管损坏具有十分重要的价值。以注蒸汽热采井过程中井筒内温度场分布情况作为主要研究内容,利用有限元分析软件ANSYS16.2建立了... 在稠油热采过程中,必然产生温度场在井筒内传递问题,了解温度场分布等情况对采油周期、出油量、出油质量、套管损坏具有十分重要的价值。以注蒸汽热采井过程中井筒内温度场分布情况作为主要研究内容,利用有限元分析软件ANSYS16.2建立了井筒环形空间温度场分布研究模型,对井筒环形空间进行温度场分析,分析出了不同油管材料下环形空间温度扩散情况。结果显示:油管导热系数对地层-水泥环-套管组合系统的温度有着明显的影响作用。 展开更多
关键词 注蒸汽采井 ANSYS 温度场 轴向 径向
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Recovery of saturated signal waveform acquired from high-energy particles with artificial neural networks 预览
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作者 Yu Liu Jing-Jun Zhu +5 位作者 Neil Roberts Ke-Ming Chen Yu-Lu Yan Shuang-Rong Mo Peng Gu Hao-Yang Xing 《核技术:英文版》 SCIE CAS CSCD 2019年第10期30-39,共10页
Artificial neural networks(ANNs)are a core component of artificial intelligence and are frequently used in machine learning.In this report,we investigate the use of ANNs to recover the saturated signals acquired in hi... Artificial neural networks(ANNs)are a core component of artificial intelligence and are frequently used in machine learning.In this report,we investigate the use of ANNs to recover the saturated signals acquired in highenergy particle and nuclear physics experiments.The inherent properties of the detector and hardware imply that particles with relatively high energies probably often generate saturated signals.Usually,these saturated signals are discarded during data processing,and therefore,some useful information is lost.Thus,it is worth restoring the saturated signals to their normal form.The mapping from a saturated signal waveform to a normal signal waveform constitutes a regression problem.Given that the scintillator and collection usually do not form a linear system,typical regression methods such as multi-parameter fitting are not immediately applicable.One important advantage of ANNs is their capability to process nonlinear regression problems.To recover the saturated signal,three typical ANNs were tested including backpropagation(BP),simple recurrent(Elman),and generalized radial basis function(GRBF)neural networks(NNs).They represent a basic network structure,a network structure with feedback,and a network structure with a kernel function,respectively.The saturated waveforms were produced mainly by the environmental gamma in a liquid scintillation detector for the China Dark Matter Detection Experiment(CDEX).The training and test data sets consisted of 6000 and 3000 recordings of background radiation,respectively,in which saturation was simulated by truncating each waveform at 40%of the maximum signal.The results show that the GBRF-NN performed best as measured using a Chi-squared test to compare the original and reconstructed signals in the region in which saturation was simulated.A comparison of the original and reconstructed signals in this region shows that the GBRF neural network produced the best performance.This ANN demonstrates a powerful efficacy in terms of solving the saturation recovery prob 展开更多
关键词 Saturated signals Artificial neural networks(ANNs) Recovery of signal waveform Generalized radial basis function Backpropagation neural network Elman neural network
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RADIAL CONVEX SOLUTIONS OF A SINGULAR DIRICHLET PROBLEM WITH THE MEAN CURVATURE OPERATOR IN MINKOWSKI SPACE 预览
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作者 梁载涛 杨艳娟 《数学物理学报:B辑英文版》 SCIE CSCD 2019年第2期395-402,共8页
In this paper, we study the existence of nontrivial radial convex solutions of a singular Dirichlet problem involving the mean curvature operator in Minkowski space. The proof is based on a well-known fixed point theo... In this paper, we study the existence of nontrivial radial convex solutions of a singular Dirichlet problem involving the mean curvature operator in Minkowski space. The proof is based on a well-known fixed point theorem in cones. We deal with more general nonlinear term than those in the literature. 展开更多
关键词 RADIAL CONVEX SOLUTIONS SINGULAR Dirichlet problem mean CURVATURE OPERATOR fixed point theorem in cones
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Improved vocal effort modeling by exploiting echo state network and radial basis function network
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作者 Chao Hao Dong Liang Liu Yongli 《中国邮电高校学报:英文版》 EI CSCD 2019年第3期98-104,共7页
The independent hypothesis between frames in vocal effect(VE) recognition makes it difficult for frame based spectral features to describe the intrinsic temporal correlation and dynamic change information in speech ph... The independent hypothesis between frames in vocal effect(VE) recognition makes it difficult for frame based spectral features to describe the intrinsic temporal correlation and dynamic change information in speech phenomena. A novel VE detection method based on echo state network(ESN) is proposed. The input sequences are mapped into a fixed-dimensionality vector in high dimensional coding space by reservoir of the ESN. Then, radial basis function(RBF) networks are employed to fit the probability density function(pdf) of each VE mode by using the vectors in the high dimensional coding space. Finally, the minimum error rate Bayesian decision is employed to judge the VE mode. The experiments which are conducted on isolated words test set achieve 79.5% average recognition accuracy, and the results show that the proposed method can overcome the defect of the independent hypothesis between frames effectively. 展开更多
关键词 VOCAL EFFORT ECHO state network RESERVOIR RADIAL basis function support VECTOR machine
New nitinol endovascular stent-graft system for abdominal aortic aneurysm with finite element analysis and experimental verification
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作者 Xiao-Chen Zhou Fan Yang +3 位作者 Xiao-Yan Gong Ming Zhao Yu-Feng Zheng Zhi-Li Sun 《稀有金属:英文版》 SCIE EI CAS CSCD 2019年第6期495-502,共8页
Abdominal aortic aneurysm(AAA) is one of the most common and catastrophic manifestations of the acute aortic syndrome that can be treated with endovascular aneurysm repair(EVAR) which requires a specially designed ste... Abdominal aortic aneurysm(AAA) is one of the most common and catastrophic manifestations of the acute aortic syndrome that can be treated with endovascular aneurysm repair(EVAR) which requires a specially designed stent-graft system.In this work, a self-expanding nickel–titanium(nitinol) stent-graft system is aiming at AAA using finite element analysis(FEA) methods to analyze both fatigue behaviors and radial forces.Based on the systematic analysis of the parametric variations, a final stent-graft system was developed by the selection and arrangement of the individual stent components, targeting an optimal performance for the treatment of AAA.Experimental tests, animal tests and clinical trials were carried out to confirm the results.Both animal trials and clinical trials showed comparable curative effects with Medtronic Endurant stent-graft(SG) systems. 展开更多
关键词 Nitinol STENT-GRAFT SYSTEM ABDOMINAL AORTIC ANEURYSM Fatigue safety factor RADIAL force Finite element analysis
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