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Advances in Manufacturing 2021年第3期9卷 430-445页

作者： Ji-Yin Zhang Chang-Feng Yao Min-Chao Cui Liang Tan Yun-Qi Sun Key Laboratory of High Performance Manufacturing for Aero Engine Northwestern Polytechnical UniversityMinistry of Industry and Information TechnologyXi’an710072People’s Republic of China Engineering Research Center of Advanced Manufacturing Technology for Aero Engine Northwestern Polytechnical UniversityMinistry of EducationXi’an710072People’s Republic of China

Residual stress during the machining process has always been a research hotspot,especially for aero-engine *** three-dimensional modeling and reconstructive laws of residual stress among various processes in the machining process of the fan blade is studied in this *** fan blades of Ti-6Al-4V are targeted for milling,polishing,heat treatment,vibratory finishing,and shot *** surface and subsurface residual stress after each process is measured by the X-ray diffraction *** distribution of the surface and subsurface residual stress is *** Rational Taylor surface function and cosine decay function are used to fit the characteristic function of the residual stress distribution,and the empirical formula with high fitting accuracy is *** value and distribution of surface and subsurface residual stress vary greatly due to different processing *** reconstructive change of the surface and subsurface residual stress of the blade in each process intuitively shows the change of the residual stress between the processes,which has a high reference significance for the research on the residual stress of the blade processing and the optimization of the entire blade process.

关键词： Fan blade Machining process Surface residual stress Subsurface residual stress three-dimensional modeling Reconstructive change

three-dimensional modeling FOR THIN PLATE-LIKE STRUCTURES INCLUDING SURFACE EFFECTS BY USING STATE SPACE METHOD

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Acta Mechanica Solida Sinica 2010年第3期23卷 260-270页

作者： Hongyu Sheng Pin Lu Institute of Civil Engineering Hefei University of Technology Hefei 230009 China Institute of Materials Research and Engineering A ^＊STAR (Agency for Science Technology and Research) 3 Research Link Singapore 117602

A three-dimensional （3-D） approach based on the state space method is proposed to study size-dependent mechanical properties of ultra-thin plate-like elastic structures considering surface effects. The structure is modeled as a laminate composed of a bulk bounded with upper and bottom surface layers, which are allowed to have different material properties from the bulk layer. State equations, including the surface properties of the structure, can be established on the basis of 3-D fundamental elasticity to analyze the size-dependent static characteristics of the thin plate-like structure. Compared with two-dimensional plate theories based size-dependent models for thin film structures in literature, the present 3-D approach is exact, which can provide benchmark results to assess the accuracy of 2-D plate theories and various numerical approaches. To show the feasibility of the proposed approach, a 3-D analytical solution for a simply supported plate-like thin structure including surface layers is derived. An algorithm is proposed for the calculation of the state equations obtained to ensure that the numerical results can reveal the surface effects clearly even for extremely thin surface layers. Numerical examples are carried out to exhibit the surface effects and some discussions are provided based on the results obtained.

关键词： micro-structures surface effects size-dependence state equation three-dimensional modeling

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Application of three-dimensional modeling in a Hydrologic Test Reach

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Meteorological and Environmental Research 2024年第6期15卷 67-69页

作者： Yuxing GAO Yiyang XIE Upstream Hydrology and Water Resources Bureau of the Yellow River Conservancy Commission Lanzhou 730030China Yellow River Survey PlanningDesign and Research Institute Co.Ltd.Zhengzhou 450003China

To address the problem that the display effect of hydrologic test data was not intuitive,the three-dimensional modeling technology of a hydrologic test reach based on GIS technology was *** reach of of the Yellow River around Lanzhou hydrological station was selected to study three-dimensional *** elevation data of river was processed through three-dimensional model constructing,water surface modeling and three-dimensional animation demonstration by using ArcGIS Pro *** on the historical highest flood level data of the test reach on September 15,1981,the real scene restoration was carried out based on the three-dimensional model,and the hydrological factors such as water depth and channel storage were *** three-dimensional modeling based on GIS technology can directly and realistically reflect the changes of topography and water surface of the test reach,and improve the application of hydrologic test results in flood control.

关键词： three-dimensional modeling Hydrologic test ArcGIS Lanzhou hydrological station

Study of the geomagnetic field's regional gradients in Chinese continent using three-dimensional surface Spline model

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Earth and Planetary Physics 2023年第1期7卷 74-83页

作者： Yan Feng YiJun Li JinYan Zhang Shuang Liu Abbas Nasir Ya Huang Institute of Space Weather Nanjing University of Information Science&TechnologyNanjing 210044China State Key Laboratory of Space Weather Chinese Academy of SciencesBeijing 100190China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao 999078China School of Electronic and Optical Engineering Nanjing University of Science and TechnologyNanjing 210094China

We combined domestic ground-based and satellite magnetic measurements to create a regional three-dimensional surface Spline(3DSS)gradient model of the main geomagnetic field over the Chinese *** improve the precision of the model,we considered the data gap between the ground and satellite *** compared and analyzed the results of the Taylor polynomial,surface Spline,and CHAOS-6(the CHAMP,?rsted and SAC-C model of Earth’s magnetic field)gradient *** showed that the gradients in the south-north and east-west directions of the four models were *** 3DSS model was able to express not only gradients at different altitudes,but also average gradients inside the research *** two Spline models were able to capture more information on gradient anomalies than were the fitted *** local anomalies were observed in northern Xinjiang,Beijing,and the junction area between Jiangsu and Zhejiang,and the total intensity F decreased whereas the altitude *** gradient decreased by 21.69%in the south-north direction and increased by 11.78%in the east-west *** addition,the altitude gradient turned from negative to positive while the altitude *** Spline model and the two fitted models differed mainly in the field sources they expressed and the modeling theory.

关键词： geomagnetic field main field gradients regional model three-dimensional modeling

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Impact of radiative cooling on the energy performance of courtyards in Mediterranean climate

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Building Simulation 2024年第9期17卷 1491-1513页

作者： Carlos-Antonio Domínguez-Torres Antonio Domínguez-Delgado Escuela Técnica Superior de Arquitectura Universidad de SevillaAv.de Reina Mercedes241012 SevillaSpain Department of Applied Mathematics 1 Escuela Técnica Superior de ArquitecturaUniversidad de SevillaAv.de Reina Mercedes241012 SevillaSpain

Radiative cooling has proven to be a useful tool to address the problems of lack of comfort and excessive energy consumption in situations of high temperatures,overheating and heat ***,incorporating courtyards in warm climate zones has been found to be highly beneficial in addressing similar ***,there is interest in analyzing the combined effects of both:radiative cooling and *** paper presents an analysis of the impact of the application of radiative cooling on a courtyard using a comprehensive simulation approach that includes a CFD model for the thermodynamic airflow in the adjacent roofs and inside the courtyard,equations for the transient heat conduction through roofs,walls and courtyard slabs,and a hybrid raytracing-radiosity model for the evaluation of the solar radiation reaching the building surfaces and its reflections,both of specular and diffuse origin,and for the calculation of the thermal radiation exchange,especially with the *** results show that in the hot season,the courtyard with radiative cooling always provides lower temperatures than the initial courtyard does,with a temperature range of 18.33℃to 33.78℃,compared to a range of 19.32℃to 38.00℃in the initial courtyard,and producing a greater difference with outdoor temperatures that can reach 12℃versus 8℃for the reference *** addition,it was found that the courtyard with radiative cooling is able to significantly reduce the observed nighttime overheating by providing lower temperatures than the outdoor temperatures in the 50%of the nights *** was also found that the thermal loads to achieve indoor thermal comfort in the spaces adjacent to the courtyard were reduced by 63.46%to 69.85%.

关键词： radiative cooling passive cooling CFD three-dimensional modeling energy saving thermal comfort

Bearing capacity and load transfer mechanism of a static drill rooted nodular pile in soft soil areas

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第10期14卷 705-719页

作者： Jia-jin ZHOU Kui-hua WANG Xiao-nan GONG Ri-hong ZHANG Research Center of Coastal and Urban Geotechnical Engineering Zhejiang University ZDOON Building Material Group

The static drill rooted nodular pile is a new type of pile foundation consisting of precast nodular pile and the surrounding cemented *** composite pile has a relatively high bearing capacity and the mud pollution will be largely reduced during the construction process by using this type of *** order to investigate the bearing capacity and load transfer mechanism of this pile,a group of experiments were conducted to provide a comparison between this new pile and the bored *** axial force of a precast nodular pile was also measured by the strain gauges installed on the pile to analyze the distribution of the axial force of the nodular pile and the skin friction supported by the surrounding soil,then 3D models were built by using the ABAQUS finite element program to investigate the load transfer mechanism of this composite pile in *** combining the results of field tests and the finite element method,the outcome showed that the bearing capacity of a static drill rooted nodular pile is higher than the bored pile,and that this composite pile will form a double stress dispersion system which will not only confirm the strength of the pile,but also make the skin friction to be fully *** settlement of this composite pile is mainly controlled by the precast nodular pile;meanwhile,the nodular pile and the surrounding cemented soil can be considered as deformation compatibility during the loading *** nodes on the nodular pile play an important role during the load transfer process,the shear strength of the interface between the cemented soil and the soil of the static drill rooted pile is larger than that of the bored pile.

关键词： Static drill rooted nodular pile Load transfer Bearing capacity ABAQUS Double stress dispersion system three-dimensional modeling

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Morphological features and endovascular repair for type B multichanneled aortic dissection: A case report

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World Journal of Clinical Cases 2023年第18期11卷 4313-4317页

作者： Wei-Feng Lu Gang Chen Li-Xin Wang Department of Vascular Surgery Zhongshan Hospital(Xiamen)Fudan UniversityXiamen 361015Fujian ProvinceChina

BACKGROUND Among the various types of aortic dissection,multichanneled aortic dissection(MCAD)differs from classic double-channeled aortic dissection and involves the formation of an additional false lumen in the aortic wall or the *** is considered a relatively rare condition with high perioperative mortality and ***,the morphological characteristic and the optimal therapeutic strategy for MCAD has not been fully *** SUMMARY A 64-year-old man presented to our hospital with severe epigastric abdominal pain radiating to the back that was associated with nausea without emesis.A computed tomography angiogram was performed that revealed a type B aortic dissection with multiple channels extending from the level of the left subclavian artery to the bilateral femoral *** used a medical three-dimensional modeling(3D)modeling system to identify the location and extension of multiple lumens from different *** also precisely located the two primary entries leading to the false lumens,which helped us to exclude the two false lumens with one *** By applying medical 3D modeling system,we discover the fragility of aortic wall and the collapse of true lumen caused by the multiple false lumens are the two morphological features of MCAD.

关键词： Aortic dissection Endovascular repair three-dimensional modeling Multichanneled Case report

CASE STUDIES OF three-dimensional NUMERICAL SIMULATION FOR TOTAL SEDIMENT TRANSPORT

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International Journal of Sediment Research 2003年第2期18卷 158-165页

作者： Hongwei FANG China Department of Hydraulic Engineering Tsinghua University Beijing 100084

The calculation of flow and sediment transport is one of the most important tasks in river engineering. The task is particularly difficult because of the many complex and interacting physical phenomena that need to be accounted for realistically in a model that has predictive power. This paper presents two study cases of three-dimensional calculation, respectively, of suspended sediment transport for the three Gorges Project on the Yangtze River, China, and of bed load transport on the Elbe River, Germany. The suspended sediment transport calculation and bed load transport calculation are compared with experimental data whenever possible.

关键词： Study case three-dimensional modeling Suspended sediment Bed load

Volume calculation of the spur gear billet for cold precision forging with average circle method

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International Journal of Coal Science & Technology 2014年第4期1卷 456-462页

作者： Wangjun Cheng Chengzhong Chi Yongzhen Wang Peng Lin Wei Liang Chen Li College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China

Forging spur gears are widely used in the driving system of mining machinery and equipment due to their higher strength and dimensional *** the purpose of precisely calculating the volume of cylindrical spur gear billet in cold precision forging,a new theoretical method named average circle method was put *** this method,a series of gear billet volumes were *** with the accurate three-dimensional modeling method,the accuracy of average circle method by theoretical calculation was estimated and the maximum relative error of average circle method was less than 1.5%,which was in good agreement with the experimental *** errors of the calculated and the experimental for obtaining the gear billet volumes with reference circle method are larger than those of the average circle *** shows that average circle method possesses a higher calculation accuracy than reference circle method(traditional method),which should be worth popularizing widely in calculation of spur gear billet volume.

关键词： Gear billet volume three-dimensional modeling Cold precision forging Average circle

Application and Design of Virtual Reality Technology in Railway Maintenance Training

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International Journal of Technology Management 2013年第4期 42-44页

作者： Li Zhu Yantai Engineering & Technology College YantaiShandongChina

Virtual reality technology is a brand new comprehensive information technology emerging during the end of 21 st century. In recent years in particular, it gains rapid development, involving industries like education, industry, military, entertainment and medicine. Combined with the characteristics of railway maintenance training, this thesis proposes the application of virtual reality in courseware, distance education, locomotive simulation driving, locomotive overhauling oil and breakdown processing, and illustrates key technology and solution of the exploitation of virtual reality technology.

关键词： Virtual reality Maintenance training three-dimensional modeling Realization of virtual function.