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On the integration of two-dimensional animation and three-dimensional art animation
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作者 Siqi Cai 《International English Education Research》 2015年第9期93-95,共3页
In recent years, with the level of science and technology progress, largely to promote the development of animation techniques. Animated film is divided into two-dimensional animation and three-dimensional animation, ... In recent years, with the level of science and technology progress, largely to promote the development of animation techniques. Animated film is divided into two-dimensional animation and three-dimensional animation, both in the retention feature animated films, based on the performance of each with different strengths, thus forming a different artistic style. Wherein the two-dimensional animation is the most common one is the most basic form of expression in animation technology is relatively mature and complete, but because of the development of animation techniques, two-dimensional animation can not meet the needs of the audience. Thus, the effective combination of two-dimensional animation and three-dimensional animation technology, the advantages of integration between the two is particularly important, so that innovation in the form of screen performance, enhance audio-visual experience. In this paper, two-dimensional animation and three-dimensional animation skills fusion analysis and research, and put forward a number of specific observations, in order to learn. 展开更多
关键词 two-dimensional animation 3-D animation integration skills
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Integration system research and development for three-dimensional laser scanning information visualization in goaf 被引量:1
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作者 罗周全 黄俊杰 +2 位作者 罗贞焱 汪伟 秦亚光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1985-1994,共10页
An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, clo... An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, cloud data de-noising optimization, construction, display and operation of three-dimensional model, model editing, profile generation, calculation of goaf volume and roof area, Boolean calculation among models and interaction with the third party soft ware. Concerning this system with a concise interface, plentiful data input/output interfaces, it is featured with high integration, simple and convenient operations of applications. According to practice, in addition to being well-adapted, this system is favorably reliable and stable. 展开更多
关键词 GOAF laser scanning visualization integration system 1 Introduction The goaf formed through underground mining of mineral resources is one of the main disaster sources threatening mine safety production [1 2]. Effective implementation of goaf detection and accurate acquisition of its spatial characteristics including the three-dimensional morphology the spatial position as well as the actual boundary and volume are important basis to analyze predict and control disasters caused by goaf. In recent years three-dimensional laser scanning technology has been effectively applied in goaf detection [3 4]. Large quantities of point cloud data that are acquired for goaf by means of the three-dimensional laser scanning system are processed relying on relevant engineering software to generate a three-dimensional model for goaf. Then a general modeling analysis and processing instrument are introduced to perform subsequent three-dimensional analysis and calculation [5 6]. Moreover related development is also carried out in fields such as three-dimensional detection and visualization of hazardous goaf detection and analysis of unstable failures in goaf extraction boundary acquisition in stope visualized computation of damage index aided design for pillar recovery and three-dimensional detection
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Reduction of signal reflection along through silicon via channel in high-speed three-dimensional integration circuit 被引量:1
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作者 刘晓贤 朱樟明 +2 位作者 杨银堂 王凤娟 丁瑞雪 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期583-590,共8页
The through silicon via (TSV) technology has proven to be the critical enabler to realize a three-dimensional (3D) gigscale system with higher performance but shorter interconnect length. However, the received dig... The through silicon via (TSV) technology has proven to be the critical enabler to realize a three-dimensional (3D) gigscale system with higher performance but shorter interconnect length. However, the received digital signal after trans- mission through a TSV channel, composed of redistribution layers (RDLs), TSVs, and bumps, is degraded at a high data-rate due to the non-idealities of the channel. We propose the Chebyshev multisection transformers to reduce the signal reflec- tion of TSV channel when operating frequency goes up to 20 GHz, by which signal reflection coefficient ($11) and signal transmission coefficient ($21) are improved remarkably by 150% and 73.3%, respectively. Both the time delay and power dissipation are also reduced by 4% and 13.3%, respectively. The resistance-inductance-conductance-capacitance (RLGC) elements of the TSV channel are iterated from scattering (S)-parameters, and the proposed method of weakening the signal reflection is verified using high frequency simulator structure (HFSS) simulation software by Ansoft. 展开更多
关键词 three-dimensional integrated circuit through silicon via channel signal reflection S-PARAMETERS
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Value of myocardial function in children with Kawasaki disease by two-dimensional and three-dimensional ultrasound speckle tracking
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作者 Ya-Mei Shen Tao-Min Bai +4 位作者 Xue-Mei Zhang Chun-Miao Kang Xiao-Ni Chang Yan-Hua Gao Xiao-Hua Yan 《Journal of Hainan Medical University》 2019年第21期58-61,共4页
Objective:To investigate the value of two-dimensional ultrasound speckle tracking(2D-STI)and three-dimensional ultrasound speckle tracking(3D-STI)in evaluating myocardial function in children with Kawasaki disease.Met... Objective:To investigate the value of two-dimensional ultrasound speckle tracking(2D-STI)and three-dimensional ultrasound speckle tracking(3D-STI)in evaluating myocardial function in children with Kawasaki disease.Methods 92 children with Kawasaki disease admitted to our hospital from February 2017 to February 2019 were retrospectively analyzed.50 children who underwent 3D-STI examination were taken as observation group and 42 children who underwent 2D-STI examination were taken as control group.The left ventricular systolic function index,storage time and analysis time of the image,the diameter of coronary artery,the strain difference of left ventricular basal segment,middle segment,apical segment and whole segment were observed.Results The levels of left ventricular end-diastolic volume(LVEDV),left ventricular end-systolic volume(LVESV),left ventricular myocardial mass(LVMI)in the observation group were higher than those in the control group(P<0.05),but there was no statistical difference in left ventricular ejection fraction(LVEF)between the two groups(P>0.05).The storage time and analysis time of the image in the observation group were significantly lower than those in the control group(P<0.05).The left coronary artery(LCA)and right coronary artery(RCA)in the observation group were higher than those in the control group(P<0.05).There was no statistical difference between left anterior descending(LAD)in the two groups(P>0.05).The longitudinal peak systolic strain(LS),circumferential peak systolic strain(CS)and radial peak systolic strain(RS)in the observation group were higher than those in the control group(P<0.05).The global longitudinal peak strain(GLS),global circumferential peak strain(GCS)and global radial peak strain(GRS)in the observation group were higher than those in the control group(P<0.05).LS and CS in the middle segment of the observation group were higher than those in the control group(P<0.05).Conclusions Compared with 2D-STI,3D-STI can objectively and accurately reflect the myocardial function of children with Kawasaki disease. 展开更多
关键词 KAWASAKI disease two-dimensional ULTRASOUND SPECKLE TRACKING three-dimensional ULTRASOUND SPECKLE TRACKING myocardial FUNCTION left ventricular systolic FUNCTION
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Study on Si-SiGe Three-Dimensional CMOS Integrated Circuits 被引量:2
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作者 胡辉勇 张鹤鸣 +2 位作者 贾新章 戴显英 宣荣喜 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第5期681-685,共5页
Based on the physical characteristics of SiGe material,a new three-dimensional (3D) CMOS IC structure is proposed,in which the first device layer is made of Si material for nMOS devices and the second device layer i... Based on the physical characteristics of SiGe material,a new three-dimensional (3D) CMOS IC structure is proposed,in which the first device layer is made of Si material for nMOS devices and the second device layer is made of Six Ge1- x material for pMOS. The intrinsic performance of ICs with the new structure is then limited by Si nMOS.The electrical characteristics of a Si-SiGe 3D CMOS device and inverter are all simulated and analyzed by MEDICI. The simulation results indicate that the Si-SiGe 3D CMOS ICs are faster than the Si-Si 3D CMOS ICs. The delay time of the 3D Si-SiGe CMOS inverter is 2-3ps,which is shorter than that of the 3D Si-Si CMOS inverter. 展开更多
关键词 SI-SIGE three-dimensional CMOS integrated circuits
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Real-time in situ three-dimensional integral videography and surgical navigation using augmented reality: a pilot study 被引量:11
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作者 Hideyuki Suenaga Huy Hoang Tran +5 位作者 Hongen Liao Ken Masamune Takeyoshi Dohi Kazuto Hoshi Yoshiyuki Mori Tsuyoshi Takato 《International Journal of Oral Science》 SCIE CAS CSCD 2013年第2期98-102,共5页
To evaluate the feasibility and accuracy of a three-dimensional augmented reality system incorporating integral videography for imaging oral and maxillofacial regions, based on preoperative computed tomography data. T... To evaluate the feasibility and accuracy of a three-dimensional augmented reality system incorporating integral videography for imaging oral and maxillofacial regions, based on preoperative computed tomography data. Three-dimensional surface models of the jawbones, based on the computed tomography data, were used to create the integral videography images of a subject's maxillofacial area. The three-dimensional augmented reality system (integral videography display, computed tomography, a position tracker and a computer) was used to generate a three-dimensional overlay that was projected on the surgical site via a half-silvered mirror. Thereafter, a feasibility study was performed on a volunteer. The accuracy of this system was verified on a solid model while simulating bone resection. Positional registration was attained by identifying and tracking the patient/surgical instrument's position. Thus, integral videography images of jawbones, teeth and the surgical tool were superimposed in the correct position. Stereoscopic images viewed from various angles were accurately displayed. Change in the viewing angle did not negatively affect the surgeon's ability to simultaneously observe the three-dimensional images and the patient, without special glasses. The difference in three-dimensional position of each measuring point on the solid model and augmented reality navigation was almost negligible (〈1 mm); this indicates that the system was highly accurate. This augmented reality system was highly accurate and effective for surgical navigation and for overlaying a three-dimensional computed tomography image on a patient's surgical area, enabling the surgeon to understand the positional relationship between the preoperative image and the actual surgical site, with the naked eye. 展开更多
关键词 augmented reality computed tomography integral videography three-dimensional image
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Through-silicon-via crosstalk model and optimization design for three-dimensional integrated circuits 被引量:3
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作者 钱利波 朱樟明 +2 位作者 夏银水 丁瑞雪 杨银堂 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期591-596,共6页
Through-silicon-via (TSV) to TSV crosstalk noise is one of the key factors affecting the signal integrity of three- dimensional integrated circuits (3D ICs). Based on the frequency dependent equivalent electrical ... Through-silicon-via (TSV) to TSV crosstalk noise is one of the key factors affecting the signal integrity of three- dimensional integrated circuits (3D ICs). Based on the frequency dependent equivalent electrical parameters for the TSV channel, an analytical crosstalk noise model is established to capture the TSV induced crosstalk noise. The impact of various design parameters including insulation dielectric, via pitch, via height, silicon conductivity, and terminal impedance on the crosstalk noise is analyzed with the proposed model. Two approaches are proposed to alleviate the TSV noise, namely, driver sizing and via shielding, and the SPICE results show 241 rnV and 379 mV reductions in the peak noise voltage, respectively. 展开更多
关键词 three-dimensional integrated circuits through-silicon-via crosstalk driver sizing via shielding
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Design and Analysis of Integrated Predictive Iterative Learning Control for Batch Process Based on Two-dimensional System Theory 被引量:3
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作者 陈宸 熊智华 钟宜生 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第7期762-768,共7页
Based on the two-dimensional (2D) system theory, an integrated predictive iterative learning control (2D-IPILC) strategy for batch processes is presented. First, the output response and the error transition model ... Based on the two-dimensional (2D) system theory, an integrated predictive iterative learning control (2D-IPILC) strategy for batch processes is presented. First, the output response and the error transition model predictions along the batch index can be calculated analytically due to the 2D Roesser model of the batch process. Then, an integrated framework of combining iterative learning control (ILC) and model predictive control (MPC) is formed reasonably. The output of feedforward ILC is estimated on the basis of the predefined process 2D model. By min- imizing a quadratic objective function, the feedback MPC is introduced to obtain better control performance for tracking problem of batch processes. Simulations on a typical batch reactor demonstrate that the satisfactory tracking performance as well as faster convergence speed can be achieved than traditional proportion type (P- t-we) ILC despite the model error and disturbances. 展开更多
关键词 lterative learning control Model predictive control integrated control Batch process two-dimensional systems
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Integrability of Nonlinear Equations of Motion on Two-Dimensional World Sheet Space-Time 被引量:2
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作者 YAN Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2X期283-287,共5页
The integrability character of nonlinear equations of motion of two-dimensional gravity with dynamical torsion and bosonic string coupling is studied in this paper. The space-like and time-like first integrals of equa... The integrability character of nonlinear equations of motion of two-dimensional gravity with dynamical torsion and bosonic string coupling is studied in this paper. The space-like and time-like first integrals of equations of motion are also found. 展开更多
关键词 two-dimensional gravity model string coupling integrABILITY
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Evaluating the use of three-dimensional reconstruction visualization technology for precise laparoscopic resection in gastroesophageal junction cancer
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作者 Dan Guo Xiao-Yan Zhu +2 位作者 Shuai Han Yu-Shu Liu Da-Peng Cui 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第5期1311-1319,共9页
BACKGROUND Laparoscopic gastrectomy for esophagogastric junction(EGJ)carcinoma enables the removal of the carcinoma at the junction between the stomach and esophagus while preserving the gastric function,thereby provi... BACKGROUND Laparoscopic gastrectomy for esophagogastric junction(EGJ)carcinoma enables the removal of the carcinoma at the junction between the stomach and esophagus while preserving the gastric function,thereby providing patients with better treatment outcomes and quality of life.Nonetheless,this surgical technique also presents some challenges and limitations.Therefore,three-dimensional reconstruction visualization technology(3D RVT)has been introduced into the procedure,providing doctors with more comprehensive and intuitive anatomical information that helps with surgical planning,navigation,and outcome evaluation.AIM To discuss the application and advantages of 3D RVT in precise laparoscopic resection of EGJ carcinomas.METHODS Data were obtained from the electronic or paper-based medical records at The First Affiliated Hospital of Hebei North University from January 2020 to June 2022.A total of 120 patients diagnosed with EGJ carcinoma were included in the study.Of these,68 underwent laparoscopic resection after computed tomography(CT)-enhanced scanning and were categorized into the 2D group,whereas 52 underwent laparoscopic resection after CT-enhanced scanning and 3D RVT and were categorized into the 3D group.This study had two outcome measures:the deviation between tumor-related factors(such as maximum tumor diameter and infiltration length)in 3D RVT and clinical reality,and surgical outcome indicators(such as operative time,intraoperative blood loss,number of lymph node dissections,R0 resection rate,postoperative hospital stay,postoperative gas discharge time,drainage tube removal time,and related complications)between the 2D and 3D groups.RESULTS Among patients included in the 3D group,27 had a maximum tumor diameter of less than 3 cm,whereas 25 had a diameter of 3 cm or more.In actual surgical observations,24 had a diameter of less than 3 cm,whereas 28 had a diameter of 3 cm or more.The findings were consistent between the two methods(χ^(2)=0.346,P=0.556),with a kappa consistency coefficient of 0.808.With respect to infiltration length,in the 3D group,23 patients had a length of less than 5 cm,whereas 29 had a length of 5 cm or more.In actual surgical observations,20 cases had a length of less than 5 cm,whereas 32 had a length of 5 cm or more.The findings were consistent between the two methods(χ^(2)=0.357,P=0.550),with a kappa consistency coefficient of 0.486.Pearson correlation analysis showed that the maximum tumor diameter and infiltration length measured using 3D RVT were positively correlated with clinical observations during surgery(r=0.814 and 0.490,both P<0.05).The 3D group had a shorter operative time(157.02±8.38 vs 183.16±23.87),less intraoperative blood loss(83.65±14.22 vs 110.94±22.05),and higher number of lymph node dissections(28.98±2.82 vs 23.56±2.77)and R0 resection rate(80.77%vs 61.64%)than the 2D group.Furthermore,the 3D group had shorter hospital stay[8(8,9)vs 13(14,16)],time to gas passage[3(3,4)vs 4(5,5)],and drainage tube removal time[4(4,5)vs 6(6,7)]than the 2D group.The complication rate was lower in the 3D group(11.54%)than in the 2D group(26.47%)(χ^(2)=4.106,P<0.05).CONCLUSION Using 3D RVT,doctors can gain a more comprehensive and intuitive understanding of the anatomy and related lesions of EGJ carcinomas,thus enabling more accurate surgical planning. 展开更多
关键词 Gastroesophageal junction cancer ENDOSCOPY Tumor resection three-dimensional reconstruction visualization two-dimensional imaging computed tomography
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Three-Dimensional Cooperative Localization via Space-Air-Ground Integrated Networks 被引量:2
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作者 Wenxuan Li Yuanpeng Liu +1 位作者 Xiaoxiang Li Yuan Shen 《China Communications》 SCIE CSCD 2022年第1期253-263,共11页
The space-air-ground integrated network(SAGIN)combines the superiority of the satellite,aerial,and ground communications,which is envisioned to provide high-precision positioning ability as well as seamless connectivi... The space-air-ground integrated network(SAGIN)combines the superiority of the satellite,aerial,and ground communications,which is envisioned to provide high-precision positioning ability as well as seamless connectivity in the 5G and Beyond 5G(B5G)systems.In this paper,we propose a three-dimensional SAGIN localization scheme for ground agents utilizing multi-source information from satellites,base stations and unmanned aerial vehicles(UAVs).Based on the designed scheme,we derive the positioning performance bound and establish a distributed maximum likelihood algorithm to jointly estimate the positions and clock offsets of ground agents.Simulation results demonstrate the validity of the SAGIN localization scheme and reveal the effects of the number of satellites,the number of base stations,the number of UAVs and clock noise on positioning performance. 展开更多
关键词 space-air-ground integrated network(SAGIN) three-dimensional(3D)localization clock noise multi-source information
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Continuous imaging space in three-dimensional integral imaging 被引量:1
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作者 张雷 杨勇 +3 位作者 王金刚 赵星 方志良 袁小聪 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期303-305,共3页
We report an integral imaging method with continuous imaging space. This method simultaneously reconstructs real and virtual images in the virtual mode, with a minimum gap that separates the entire imaging space into ... We report an integral imaging method with continuous imaging space. This method simultaneously reconstructs real and virtual images in the virtual mode, with a minimum gap that separates the entire imaging space into real and virtual space. Experimental results show that the gap is reduced to 45% of that in a conventional integral imaging system with the same parameters. 展开更多
关键词 three-dimensional integral imaging imaging space
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Forming mechanism of three-dimensional integral fin based on flat surface
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作者 向建化 段吉安 +3 位作者 周海波 张春良 刘贵云 周超 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1660-1666,共7页
To improve heat-transfer performance, a novel integral three-dimensional fin-structure on the plat surface was presented to increase the evaporation efficiency. The three-dimensional fin-structure is composed of a spi... To improve heat-transfer performance, a novel integral three-dimensional fin-structure on the plat surface was presented to increase the evaporation efficiency. The three-dimensional fin-structure is composed of a spiral micro-groove and multi radial micro-grooves. Both ploughing-extrusion(P-E) and stamping were used to form the integral-fins with a connection between radial and circumferential directions. Based on the SEM results, the relationships among P-E speed v P-E, rotational speed np and feed fp, and among interference length Li, stamping feed angle θc and stamping depth ac were analyzed. The effects of processing parameters on the groove morphology and the matching relationship between parameters were also discussed. The integral finned surface with micro-grooves and cracks can be obtained under such processing conditions: P-E depth ap=0.3 mm, ac=0.3 mm, the interval of helical groove dp=1.24 mm, θc=2° and np=50 r/min. 展开更多
关键词 three-dimensional integral fin ploughing-extrusion STAMPING micro groove enhanced boiling
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A class of two-dimensional dual integral equations and its application
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作者 范天佑 孙竹凤 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第2期247-252,共6页
Because exact analytic solution is not available, we use double expansion and boundary collocation to construct an approximate solution for a class of two-dimensional dual integral equations in mathematical physics. T... Because exact analytic solution is not available, we use double expansion and boundary collocation to construct an approximate solution for a class of two-dimensional dual integral equations in mathematical physics. The integral equations by this procedure are reduced to infinite algebraic equations. The accuracy of the solution lies in the boundary collocation technique. The application of which for some complicated initialboundary value problems in solid mechanics indicates the method is powerful. 展开更多
关键词 two-dimensional dual integral equation double expansion boundary collocation
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Numerical solutions of two-dimensional nonlinear integral equations via Laguerre Wavelet method with convergence analysis
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作者 K.Maleknejad M.Soleiman Dehkordi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2021年第1期83-98,共16页
In this paper,the approximate solutions for two different type of two-dimensional nonlinear integral equations:two-dimensional nonlinear Volterra-Fredholm integral equations and the nonlinear mixed Volterra-Fredholm i... In this paper,the approximate solutions for two different type of two-dimensional nonlinear integral equations:two-dimensional nonlinear Volterra-Fredholm integral equations and the nonlinear mixed Volterra-Fredholm integral equations are obtained using the Laguerre wavelet method.To do this,these two-dimensional nonlinear integral equations are transformed into a system of nonlinear algebraic equations in matrix form.By solving these systems,unknown coefficients are obtained.Also,some theorems are proved for convergence analysis.Some numerical examples are presented and results are compared with the analytical solution to demonstrate the validity and applicability of the proposed method. 展开更多
关键词 he two-dimensional nonlinear integral equations the nonlinear mixed Volterra-Fredholm inte-gral equations two-dimensional Laguerre wavelet Orthogonal polynomial convergence analysis the Darboux problem.
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High Optical Magnification Three-Dimensional Integral Imaging of Biological Micro-organism
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作者 孙聃 陆瑶 +1 位作者 郝劲波 王凯歌 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期76-79,共4页
A high optical magnification three-dimensional imaging system is proposed using an optic microscope whose ocular (eyepiece) is retained and the structure of the transmission mode is not destroyed. The elemental imag... A high optical magnification three-dimensional imaging system is proposed using an optic microscope whose ocular (eyepiece) is retained and the structure of the transmission mode is not destroyed. The elemental image array is captured through the micro lens array. Due to the front diffuse transmission element, each micro lens sees a slightly different spatial perspective of the scene, and a different independent image is formed in each micro lens channel. Each micro lens channel is imaged by a Fourier lens and captured by a CCD. The design translating the stage in x or y provides no parallax. Compared with the conventional integral imaging of micro-objects, the optical magnification of micro-objects in the proposed system can enhanced remarkably. The principle of the enhancement of the image depth is explained in detail and the experimental results are presented. 展开更多
关键词 High Optical Magnification three-dimensional integral Imaging of Biological Micro-organism
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Research of Tile Type Transceiver Module Integrating with Two-Dimensional Sum Difference Network
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作者 Taifu Zhou Jian Zhang 《Journal of Computer and Communications》 2021年第12期116-124,共9页
<div style="text-align:justify;"> Transceiver module and two-dimensional sum difference network are important components of phased array antenna. In this paper, multilayer printed board is used to inte... <div style="text-align:justify;"> Transceiver module and two-dimensional sum difference network are important components of phased array antenna. In this paper, multilayer printed board is used to integrate millimeter wave multi-channel transceiver circuit and sum difference network. The interconnection between them is realized through RF coaxial vertical transition. At the same time, the heat dissipation design and inter channel shielding design of the module are carried out. The RF and low frequency required by the module are completed through the wiring between and within the dielectric plate layers. Finally, 128 arrays are fabricated and verified by multi-channel passive test. The results show that the type transceiver module integrating with two-dimensional sum difference network has good performance, and 128 channels have excellent amplitude and phase characteristics. The integration technology has the characteristics of lightweight, miniaturization, high integration and low manufacturing cost. It can be widely used in miniaturized phased array antennas. </div> 展开更多
关键词 Multi-Channel Transceiver two-dimensional Sum Difference Network RF Coaxial Vertical Transition High integration
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Interaction of two three-dimensional explosion bubbles 被引量:2
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作者 YAO Xiong-liang ZHANG A-man LIU Yu-chen 《Journal of Marine Science and Application》 2007年第2期12-18,共7页
The interaction of two underwater explosion bubbles was mathematically analyzed in this paper. Based on the assumption of potential flow, high-order curved elements were used to discretize the boundary integral equati... The interaction of two underwater explosion bubbles was mathematically analyzed in this paper. Based on the assumption of potential flow, high-order curved elements were used to discretize the boundary integral equation and solve it. Assuming that gas inside the bubble follows the isentropic rule, the Euler-Lagrange method was used to trace the evolution of the bubble, and when calculating the singular integral, the singularity of the double-layer singular integral was eliminated by reconstructing a principal-value integral of double-layer potential so that a more precise result could be obtained. Elastic mesh technique (EMT) was also used when tracing the evolution of the bubble interface, and numerical smoothing wasn't needed. A comparison of calculations using this three-dimensional model with results of the Reyleigh-Plesset bubble model shows that the three-dimensional model and calculation method in this paper is practical. This three-dimensional model was applied to simulate the interaction of two bubbles under the action of gravity, and the dynamic characteristics of two bubbles near the surface was also analyzed. Bubbles influenced by surface effects and gravity present severe non-linearity. This paper provides a reference for research into the dynamics of multi-bubbles. 展开更多
关键词 two bubbles boundary integral EMT three-dimensional model
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Three-Dimensional Analysis of Rolling by Twin Shear Stress Yield Criterion 被引量:4
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作者 ZHAO De-wen XIE Ying-jie LIU Xiang-hua WANG Guo-dong 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2006年第6期21-26,共6页
Using the twin shear stress yield criterion, the surface integral of the co-line vectors, and the integration depending on upper limit, Kobayashi's three-dimensional velocity field of rolling was analyzed and an anal... Using the twin shear stress yield criterion, the surface integral of the co-line vectors, and the integration depending on upper limit, Kobayashi's three-dimensional velocity field of rolling was analyzed and an analytical expression of rolling torque and single force was obtained. Through redoing the same experiment of rolling pure lead as Sims, the calculated results by the above expression were compared with those of Kobayashi and Sims formulae. The results show that the twin shear stress yield criterion is available for rolling analysis and the calculated results by the new formula are a little higher than those by Kobayashi and Sims ones if the reduction ratio is less than 30%. 展开更多
关键词 twin shear stress yield criterion co-line vector integral three-dimensional rolling analytical solution
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Microstructure-based three-dimensional characterization of chip formation and surface generation in the machining of particulate-reinforced metal matrix composites 被引量:2
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作者 Qi Wu Liangchi Zhang 《International Journal of Extreme Manufacturing》 EI 2020年第4期74-85,共12页
Particulate-reinforced metal matrix composites(PRMMCs)are difficult to machine due to the inclusion of hard,brittle reinforcing particles.Existing experimental investigations rarely reveal the complex material removal... Particulate-reinforced metal matrix composites(PRMMCs)are difficult to machine due to the inclusion of hard,brittle reinforcing particles.Existing experimental investigations rarely reveal the complex material removal mechanisms(MRMs)involved in the machining of PRMMCs.This paper develops a three-dimensional(3D)microstructure-based model for investigating the MRM and surface integrity of machined PRMMCs.To accurately mimic the actual microstructure of a PRMMC,polyhedrons were randomly distributed inside the matrix to represent irregular SiC particles.Particle fracture and matrix deformation and failure were taken into account.For the model’s capability comparison,a two-dimensional(2D)analysis was also conducted.Relevant cutting experiments showed that the established 3D model accurately predicted the material removal,chip morphology,machined surface finish,and cutting forces.It was found that the matrix-particle-tool interactions led to particle fractures,mainly in the primary shear and secondary deformation zones along the cutting path and beneath the machined surface.Particle fracture and dilodegment greatly influences the quality of a machined surface.It was also found that although a 2D model can reflect certain material removal features,its ability to predict microstructural variation is limited. 展开更多
关键词 particulate-reinforced metal-matrix composites MMCS finite element three-dimensional modelling particle fracture material removal surface integrity
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