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Using Augmented Reality Techniques to Simulate Training and Assistance in Electric Power 预览
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作者 Zifeng Tang Jiyao Deng +4 位作者 Hao Gao Jiageng Song Qinlun Li Peixin Zhang Minghui Sun 《国际计算机前沿大会会议论文集》 2019年第2期587-589,共3页
In combination with the augmented reality (AR) technology and Hololens device, an electric power work assist system is developed to provide a more realistic and convenient training experience for electric power traini... In combination with the augmented reality (AR) technology and Hololens device, an electric power work assist system is developed to provide a more realistic and convenient training experience for electric power training. The training effect was improved, and help guidance information was provided in the actual operation of electric power work. Experimental results show that difficulty of electric power work is reduced and the efficiency of actual work is improved. 展开更多
关键词 ELECTRIC POWER simulation TRAINING ELECTRIC POWER work ASSISTANCE AUGMENTED reality Image recognition
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Numerical study of a guide-vane-augmented vertical darrieus tidal-currentturbine 预览
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作者 Zhen Liu Zhi-meng Wang +1 位作者 Hong-da Shi Heng-liang Qu 《水动力学研究与进展:英文版》 SCIE EI CSCD 2019年第3期522-530,共9页
It is reported that the augmented vertical axis turbine (VAT) has a better operating performance. A guide-vane type augmentation is proposed in this study, with a simpler outline and a better adaptability to various d... It is reported that the augmented vertical axis turbine (VAT) has a better operating performance. A guide-vane type augmentation is proposed in this study, with a simpler outline and a better adaptability to various directions of the incident water flow, as compared to the duct-type diffuser. A 2?D numerical model based on the computational fluid dynamics software ANSYS-Fluent is established and validated by experimental data. It is found that the guide vanes could narrow the flow path together with the VAT rotor and increase the flow velocity around the blades. The fluctuation of the instantaneous torque output is significantly reduced by using the guide-vane stator. The numerical results indicate that a four blades setup is suitable for the stator and the chord length of the guide vane should be equal to that of the rotor blade. The gap between the stator and the rotor is suggested to be a quarter of the chord length of the rotor blades. The non-zero pitch angle of the guide vane is found to have negative effects on the torque and the power output. The averaged power and torque coefficients for three non-zero directional angles of the incident flow are approximately 30% lower than those for the zero-directional angle. 展开更多
关键词 Tidal current energy VERTICAL axis turbine AUGMENTED rotor GUIDE VANE numerical simulation
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Oscillatory-Plus-Transient Signal Decomposition Using TQWT and MCA 预览
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作者 G. Ravi Shankar Reddy Rameshwar Rao 《电子科技学刊:英文版》 CAS CSCD 2019年第2期135-151,共17页
This paper describes a method for decomposing a signal into the sum of an oscillatory component and a transient component. The process uses the tunable Q-factor wavelet transform (TQWT): The oscillatory component is m... This paper describes a method for decomposing a signal into the sum of an oscillatory component and a transient component. The process uses the tunable Q-factor wavelet transform (TQWT): The oscillatory component is modeled as a signal that can be sparsely denoted by high Q-factor TQWT;similarly, the transient component is modeled as a piecewise smooth signal that can be sparsely denoted using low Q-factor TQWT. Since the low and high Q-factor TQWT has low coherence, the morphological component analysis (MCA) can effectively decompose the signal into oscillatory and transient components. The corresponding optimization problem of MCA is resolved by the split augmented Lagrangian shrinkage algorithm (SALSA). The applications of the proposed method to speech, electroencephalo-graph (EEG), and electrocardiograph (ECG) signals are included. 展开更多
关键词 Morphological COMPONENT analysis (MCA) OSCILLATORY COMPONENT split AUGMENTED LAGRANGIAN shrinkage algorithm (SALSA) transient COMPONENT tunable Q-factor wavelet transform (TQWT)
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Design of an augmented reality display based on polarization grating
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作者 夏人杰 王长顺 +3 位作者 潘雨佳 陈天宇 吕子瑶 孙丽丽 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第7期216-221,共6页
A new optical system for an augmented reality(AR) display is proposed in this paper.The optical system mainly includes a ray deflector, coupling input grating, optical waveguide, and coupling output grating.Both the r... A new optical system for an augmented reality(AR) display is proposed in this paper.The optical system mainly includes a ray deflector, coupling input grating, optical waveguide, and coupling output grating.Both the ray deflector and the coupling input grating are designed based on the diffraction characteristics of the polarization grating, and the coupling output grating is the Bragg reflection grating.Compared with other AR schemes, this AR optical system not only reduces the number of projections from two to one, but also improves the efficiency of light coupling into the optical waveguides.The energy loss is reduced by utilizing the single-order diffraction characteristics of the polarization grating in its coupling input structure.The light deflector uses the polarization selectivity of the polarization grating and the characteristics of the rotating light of the twisted nematic liquid crystal layer to realize beam deflection.The working principle of the optical system is experimentally and theoretically demonstrated. 展开更多
关键词 AUGMENTED REALITY POLARIZATION GRATING AZO liquid crystal
Application and Prospect of Mixed Reality Technology in Medical Field 预览
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作者 Hong-zhi HU Xiao-bo FENG +4 位作者 Zeng-wu SHAO Mao XIE Song XU Xing-huo WU Zhe-wei YE 《当代医学科学(英文)》 SCIE CAS 2019年第1期1-6,共6页
Mixed reality(MR)technology is a new digital holographic image technology,which appears in the field of graphics after virtual reality(VR)and augmented reality(AR)technology,a new interdisciplinary frontier.As a new g... Mixed reality(MR)technology is a new digital holographic image technology,which appears in the field of graphics after virtual reality(VR)and augmented reality(AR)technology,a new interdisciplinary frontier.As a new generation of technology,MR has attracted great attention of clinicians in recent years.The emergence of MR will bring about revolutionary changes in medical education training,medical research,medical communication,and clinical treatment.At present,MR technology has become the popular frontline information technology for medical applications.With the popularization of digital technology in the medical field,the development prospects of MR are inestimable.The purpose of this review article is to introduce the application of MR technology in the medical field and prospect its trend in the future. 展开更多
关键词 MIXED REALITY AUGMENTED REALITY VIRTUAL REALITY education SURGERY
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Mobile Web Augmented Reality in 5G and Beyond:Challenges,Opportunities,and Future Directions 预览
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作者 Xiuquan Qiao Pei Ren +3 位作者 Guoshun Nan Ling Liu Schahram Dustdar Junliang Chen 《中国通信:英文版》 SCIE CSCD 2019年第9期141-154,共14页
The popularity of wearable devices and smartphones has fueled the development of Mobile Augmented Reality(MAR),which provides immersive experiences over the real world using techniques,such as computer vision and deep... The popularity of wearable devices and smartphones has fueled the development of Mobile Augmented Reality(MAR),which provides immersive experiences over the real world using techniques,such as computer vision and deep learning.However,the hardware-specific MAR is costly and heavy,and the App-based MAR requires an additional download and installation and it also lacks cross-platform ability.These limitations hamper the pervasive promotion of MAR.This paper argues that mobile Web AR(MWAR)holds the potential to become a practical and pervasive solution that can effectively scale to millions of end-users because MWAR can be developed as a lightweight,cross-platform,and low-cost solution for end-to-end delivery of MAR.The main challenges for making MWAR a reality lie in the low efficiency for dense computing in Web browsers,a large delay for real-time interactions over mobile networks,and the lack of standardization.The good news is that the newly emerging 5G and Beyond 5G(B5G)cellular networks can mitigate these issues to some extent via techniques such as network slicing,device-to-device communication,and mobile edge computing.In this paper,we first give an overview of the challenges and opportunities of MWAR in the 5G era.Then we describe our design and development of a generic service-oriented framework(called MWAR5)to provide a scalable,flexible,and easy to deploy MWAR solution.We evaluate the performance of our MWAR5 system in an actually deployed 5G trial network under the collaborative configurations,which shows encouraging results.Moreover,we also share the experiences and insights from our development and deployment,including some exciting future directions of MWAR over 5G and B5G networks. 展开更多
关键词 5G edge computing augmentedreality mobile augmented reality Web augmentedreality
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Inverse design of low boom configurations using proper orthogonal decomposition and augmented Burgers equation
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作者 Yidian ZHANG Jiangtao HUANG +2 位作者 Zhenghong GAO Chao WANG Bowen SHU 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第6期1380-1389,共10页
Mitigation of sonic boom to an acceptable stage is a key point for the next generation of supersonic transports. Meanwhile, designing a supersonic aircraft with an ideal ground signature is always the focus of researc... Mitigation of sonic boom to an acceptable stage is a key point for the next generation of supersonic transports. Meanwhile, designing a supersonic aircraft with an ideal ground signature is always the focus of research on sonic boom reduction. This paper presents an inverse design approach to optimize the near-field signature of an aircraft, making it close to the shaped ideal ground signature after the propagation in the atmosphere. Using the Proper Orthogonal Decomposition(POD) method, a guessed input of augmented Burgers equation is inversely achieved. By multiple POD iterations, the guessed ground signatures successively approach the target ground signature until the convergence criteria is reached. Finally, the corresponding equivalent area distribution is calculated from the optimal near-field signature through the classical Whitham F-function theory. To validate this method, an optimization example of Lockheed Martin 1021 is demonstrated. The modified configuration has a fully shaped ground signature and achieves a drop of perceived loudness by 7.94 PLdB. This improvement is achieved via shaping the original near-field signature into wiggles and damping it by atmospheric attenuation. At last, a nonphysical ground signature is set as the target to test the robustness of this inverse design method and shows that this method is robust enough for various inputs. 展开更多
关键词 Aeroacoustics AUGMENTED BURGERS equation LOW BOOM configuration Optimization Supersonic AERODYNAMICS
Plug-and-Play Based Optimization Algorithm for New Crime Density Estimation
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作者 Xiang-Chu Feng Chen-Ping Zhao +2 位作者 Si-Long Peng Xi-Yuan Hu Zhao-Wei Ouyang 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第2期476-493,共18页
Different from a general density estimation,the crime density estimation usually has one important factor:the geographical constraint.In this paper,a new crime density estimation model is formulated,in which the regio... Different from a general density estimation,the crime density estimation usually has one important factor:the geographical constraint.In this paper,a new crime density estimation model is formulated,in which the regions where crime is impossible to happen,such as mountains and lakes,are excluded.To further optimize the estimation method,a learning-based algorithm,named Plug-and-Play,is implanted into the augmented Lagrangian scheme,which involves an off-the-shelf filtering operator.Different selections of the filtering operator make the algorithm correspond to several classical estimation models.Therefore,the proposed Plug-and-Play optimization based estimation algorithm can be regarded as the extended version and general form of several classical methods.In the experiment part,synthetic examples with different invalid regions and samples of various distributions are first tested.Then under complex geographic constraints,we apply the proposed method with a real crime dataset to recover the density estimation.The state-of-the-art results show the feasibility of the proposed model. 展开更多
关键词 CRIME density estimation AUGMENTED LAGRANGIAN strategy Plug-and-Play filtering operator
Up-to-date intraoperative computer assisted solutions for liver surgery 预览
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作者 Apollon Zygomalas Ioannis Kehagias 《世界胃肠外科杂志:英文版(电子版)》 2019年第1期1-10,共10页
Computer assisted surgical planning allowed for a better selection of patients,evaluation of operative strategy,appropriate volumetric measurements,identification of anatomical risks,definition of tumour resection mar... Computer assisted surgical planning allowed for a better selection of patients,evaluation of operative strategy,appropriate volumetric measurements,identification of anatomical risks,definition of tumour resection margins and choice of surgical approach in liver oncologic resections and living donor liver transplantations.Although preoperative computer surgical analysis has been widely used in daily clinical practice,intraoperative computer assisted solutions for risk analysis and navigation in liver surgery are not widely available or still under clinical evaluation.Computer science technology can efficiently assist modern surgeons during complex liver operations,mainly by providing image guidance with individualized 2D images and 3D models of the various anatomical and pathological structures of interest.Intraoperative computer assisted liver surgery is particularly useful in complex parenchyma-sparing hepatectomies,for intraoperative risk analysis and for the effective treatment of colorectal metastases after neoadjuvant therapy or when they are multiple.In laparoscopic liver surgery,intraoperative computer aid is definitively more important as,apart from a restricted field of view,there is also loss of the fine haptic feedback.Intraoperative computer assisted developments face challenges that prevent their application in daily clinical practice.There is a vast variety of studies regarding intraoperative computer assisted liver surgery but there are no clear objective measurements in order to compare them and select the most effective solutions.An overview of up-to-date intraoperative computer assisted solutions for liver surgery will be discussed. 展开更多
关键词 Computer assisted SURGERY Liver INTRAOPERATIVE 3D models Navigation Image guidance AUGMENTED REALITY Hepatic SURGERY HEPATECTOMY
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Implementing Augmented Reality in Learning 预览
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作者 Ajit Singh 《心理学研究:英文版》 2019年第4期172-177,共6页
Technologies are changing and ever growing.One of the newest developing technologies is augmented reality(AR),which can be applied to many different existing technologies,such as computers,tablets,and smartphones.AR t... Technologies are changing and ever growing.One of the newest developing technologies is augmented reality(AR),which can be applied to many different existing technologies,such as computers,tablets,and smartphones.AR technology can also be utilized through wearable components,for example,glasses.Throughout this paper review on AR,the following aspects are discussed at length:research explored,theoretical foundations,applications in education,challenges,reactions,and implications.Several different types of AR devices and applications are discussed at length,and an in-depth analysis is done on several studies that have implemented AR technology in an educational setting. 展开更多
关键词 AUGMENTED REALITY LEARNING and development EDUCATOR flow theory JUST-IN-TIME LEARNING
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Launching a paradigm for first and redo-surgery in primary congenital glaucoma: institutional experience
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作者 Tharwat H. Mokbel Eman M. El Hefney +5 位作者 Sherein M. Hagras Amani E. Badawi Manal A. Kasem Ahmed A. Al Nagdy Sherief E. El Khouly Walid M. Gaafar 《国际眼科杂志:英文版》 SCIE CAS 2019年第2期226-234,共9页
AIM:To evaluate the outcome of the initial and the redo-surgeries for primary congenital glaucoma(PCG) correlated to its degree of severity. METHODS:A retrospective study involved patients with PCG presented between 2... AIM:To evaluate the outcome of the initial and the redo-surgeries for primary congenital glaucoma(PCG) correlated to its degree of severity. METHODS:A retrospective study involved patients with PCG presented between 2010 and 2018. Medical records were reviewed to assess the degree of the preoperative severity according to the intraocular pressure(IOP), corneal diameter and corneal edema. Success and failure rates were calculated for both first and redo-surgeries at 6 and 12 mo respectively then correlated to the severity of the cases. RESULTS:Complete records were retrieved for 272 eyes(153 patients) with PCG:43 eyes were mild, 136 moderate and 93 severe. Combined trabeculotomy and trabeculectomy(CTT) had the highest success rate in moderate(96.4%) and severe cases(59.3%) while trabeculotomy had the highest success rate in mild cases(96.3%). Medical records of 88 eyes(63 patients) with recurrent PCG were analyzed, most with severe presentation(59 eyes). Ahmed glaucoma valve(AGV) was used in 67(76%) eyes and augmented trabeculectomy in 21(24%) eyes. At 12 mo, there was no statistically significant difference between both surgeries in total success rate(P=0.256). For mild cases, success rate was 100% for both surgeries. Severe cases had higher success rates following AGV(87%) than augmented trabeculectomy(20%). Preoperative severity of the disease was an independent factor affecting the failure rate in secondary trabeculectomy but not in AGV. Patients younger than 24 mo had higher probabilities of failure following both redo-surgeries with hazard ratio =1.325 and 0.37 for augmented trabeculectomy and AGV respectively. CONCLUSION:Preoperative assessment of the severity of eyes with PCG helps in the selecting the optimal primary and secondary surgery. For first surgery, trabeculotomy is more effective in mild cases whereas;CTT and augmented subscleral trabeculectomy(SST) are appropriate for moderate and severe cases. AGV proved to be superior to augmented SST in severe recurrent cases. 展开更多
关键词 AHMED GLAUCOMA valve AUGMENTED TRABECULECTOMY Egypt primary congenital GLAUCOMA
Augmented reality technology for preoperative planning and intraoperative navigation during hepatobiliary surgery:A review of current methods 预览
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作者 Rui Tang Long-Fei Ma +5 位作者 Zhi-Xia Rong Mo-Dan Li Jian-Ping Zeng Xue-Dong Wang Hong-En Liao Jia-Hong Dong 《国际肝胆胰疾病杂志:英文版》 SCIE CAS CSCD 2018年第2期101-112,共12页
Background:Augmented reality(AR)technology is used to reconstruct three-dimensional(3D)images of hepatic and biliary structures from computed tomography and magnetic resonance imaging data,and to superimpose the virtu... Background:Augmented reality(AR)technology is used to reconstruct three-dimensional(3D)images of hepatic and biliary structures from computed tomography and magnetic resonance imaging data,and to superimpose the virtual images onto a view of the surgical field.In liver surgery,these superimposed virtual images help the surgeon to visualize intrahepatic structures and therefore,to operate precisely and to improve clinical outcomes.Data Sources:The keywords“augmented reality”,“liver”,“laparoscopic”and“hepatectomy”were used for searching publications in the PubMed database.The primary source of literatures was from peer-reviewed journals up to December 2016.Additional articles were identified by manual search of references found in the key articles.Results:In general,AR technology mainly includes 3D reconstruction,display,registration as well as tracking techniques and has recently been adopted gradually for liver surgeries including laparoscopy and laparotomy with video-based AR assisted laparoscopic resection as the main technical application.By applying AR technology,blood vessels and tumor structures in the liver can be displayed during surgery,which permits precise navigation during complex surgical procedures.Liver transformation and registration errors during surgery were the main factors that limit the application of AR technology.Conclusions:With recent advances,AR technologies have the potential to improve hepatobiliary surgical procedures.However,additional clinical studies will be required to evaluate AR as a tool for reducing postoperative morbidity and mortality and for the improvement of long-term clinical outcomes.Future research is needed in the fusion of multiple imaging modalities,improving biomechanical liver modeling,and enhancing image data processing and tracking technologies to increase the accuracy of current AR methods.. 展开更多
关键词 AUGMENTED REALITY IMAGE-GUIDED SURGERY LIVER SURGERY 3D TECHNOLOGY
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Existence and Stability of Steady State in an Augmented Solow Model with Multiple Capital Goods
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作者 Jian Li Yao Lu 《中国经济学前沿:英文版》 2018年第4期685-702,共18页
This paper relaxes two assumptions on the traditional augmented Solow model:strict concavity of production functions and dual capital goods.It generalizes traditional conclusions of the Solow model by demonstrating th... This paper relaxes two assumptions on the traditional augmented Solow model:strict concavity of production functions and dual capital goods.It generalizes traditional conclusions of the Solow model by demonstrating that neoclassical properties of a production function are sufficient for the existence and global stability of the steady state in the augmented Solow model with multiple capital goods.Moreover,we prove necessity of essentiality of inputs for a neoclassical production function and generalize the golden rule of capital accumulation. 展开更多
关键词 MULTIPLE capital goods AUGMENTED Solow model ESSENTIALITY of inputs steady state STRICT CONCAVITY
A Geometry-Based Point Cloud Reduction Method for MobileAugmented Reality System
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作者 Hao-Ren Wang Juan Lei +1 位作者 Ao Li Yi-Hong Wu 《计算机科学技术学报:英文版》 SCIE EI CSCD 2018年第6期1164-1177,共14页
In this paper, a geometry-based point cloud reduction method is proposed, and a real-time mobile augmentedreality system is explored for applications in urban environments. We formulate a new objective function which ... In this paper, a geometry-based point cloud reduction method is proposed, and a real-time mobile augmentedreality system is explored for applications in urban environments. We formulate a new objective function which combinesthe point reconstruction errors and constraints on spatial point distribution. Based on this formulation, a mixed integerprogramming scheme is utilized to solve the points reduction problem. The mobile augmented reality system explored inthis paper is composed of the ofttine and online stages. At the offline stage, we build up the localization database usingstructure from motion and compress the point cloud by the proposed point cloud reduction method. While at the onlinestage, we compute the camera pose in real time by combining an image-based localization algorithm and a continuous posetracking algorithm. Experimental results on benchmark and real data show that compared with the existing methods, thisgeometry-based point cloud reduction method selects a point cloud subset which helps the image-based localization methodto achieve higher success rate. Also, the experiments conducted on a mobile platform show that the reduced point cloud notonly reduces the time consuming for initialization and re-initialization, but also makes the memory footprint small, resultinga scalable and real-time mobile augmented reality system. 展开更多
关键词 MOBILE PLATFORM AUGMENTED REALITY point CLOUD reduction structure from MOTION
基于改进平方根UKF双向滤波的单站无源定位算法 预览 被引量:2
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作者 张智 姜秋喜 孙志勇 《火力与指挥控制》 CSCD 北大核心 2015年第3期116-120,共5页
针对单站无源定位可观测性弱、观测噪声大而导致的定位精度低、稳定性差和收敛速度慢等问题,在结合平方根无迹卡尔曼滤波(Square~Root Unscented Kalman Filter,SRUKF)以及后向平滑思想的基础上,提出了一种改进SRUKF的双向滤波算... 针对单站无源定位可观测性弱、观测噪声大而导致的定位精度低、稳定性差和收敛速度慢等问题,在结合平方根无迹卡尔曼滤波(Square~Root Unscented Kalman Filter,SRUKF)以及后向平滑思想的基础上,提出了一种改进SRUKF的双向滤波算法。该算法采用Q—R分解的形式,使用误差协方差的平方根代替协方差参与递推运算,提高了算法的稳定性与运算效率。同时,该算法对状态向量进行扩维,将过程噪声与观测噪声通过非线性系统传播,降低了噪声对滤波精度的影响,并利用当前时刻滤波结果通过Rauch—Tung—Striebel(RTS)后向平滑得到再次前向滤波更高精度的起始值,提高了算法的定位精度与收敛速度。仿真结果表明,新算法在保证实时性的基础上改善了单站无源定位的性能。 展开更多
关键词 单站无源定位 平方根无迹卡尔曼滤波 后向平滑 Q—R分解 扩维
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Some modifications to the process of discontinuous deformationanalysis
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作者 Yong Yu Jianmin Yin 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2015年第1期95-100,共6页
This paper presents a modified method of discontinuous deformation analysis (DDA). In the presentedmethod, open-close iteration may not be needed, small penetration is permitted among blocks, andsprings are added be... This paper presents a modified method of discontinuous deformation analysis (DDA). In the presentedmethod, open-close iteration may not be needed, small penetration is permitted among blocks, andsprings are added between contacting block pairs only when a penetration takes place. The three contactpatterns (i.e. sliding, locking and opening) in original DDA method are not involved, and the recognitionof these contact patterns and treatment of transformation among patterns are not required either,significantly saving the computing time. In a convex to concave contact, there are two candidate entranceedges which may cause uncertainty. In this case, we propose the angle bisector criterion to determine theentrance edge. The spring stiffness is much larger than Young's modulus in the original DDA, however wefind that the correct results can still be obtained when it is much smaller than Young's modulus. Finally,the penetrations by using penalty method and augmented Lagrangian method are compared. Penetrationof the latter is 1/4 of the former. The range of spring stiffness for the latter is wider than the former,being 0.01e1 of the former. Both methods can lead to correct contact forces. 2015 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved. 展开更多
关键词 Discontinuous deformation ANALYSIS (DDA) Open-close ITERATION CONTACT force Vertexevertex CONTACT Angle BISECTOR AUGMENTED Lagrangian method (ALM)
Unscented Kalman filtering in the additive noise case 被引量:3
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《中国科学:技术科学英文版》 SCIE EI CAS 2010年第4期929-941,共13页
The unscented Kalman filter(UKF) has four implementations in the additive noise case,according to whether the state is augmented with noise vectors and whether a new set of sigma points is redrawn from the predicted ... The unscented Kalman filter(UKF) has four implementations in the additive noise case,according to whether the state is augmented with noise vectors and whether a new set of sigma points is redrawn from the predicted state(which is so-called resampling) for the observation prediction.This paper concerns the differences of performances for those implementations,such as accuracy,adaptability,computational complexity,etc.The conditionally equivalent relationships between the augmented and non-augmented unscented transforms(UTs) are proved for several sampling strategies that are commonly used.Then,we find that the augmented and non-augmented UKFs have the same filter results with the additive measurement noise,but only have the same state predictions with the additive process noise.Resampling is not believed to be necessary in some researches.However,we find out that resampling can be helpful for an adaptive Kalman gain.This will improve the convergence and accuracy of the filter when the large scale state modeling bias or unknown maneuvers occur.Finally,some universal designing principles for a practical UKF are given as follows:1) for the additive observation noise case,it’s better to use the non-augmented UKF;2) for the additive process noise case,when the small state modeling bias or maneuvers are involved,the non-resampling algorithms with state whether augmented or not are candidates for filters;3) the resampling and non-augmented algorithm is the only choice while the large state modeling bias or maneuvers are latent. 展开更多
关键词 unscented KALMAN filter ADDITIVE noise unscented TRANSFORMATION AUGMENTED redraw SIGMA POINTS adaptive
一种扩维无迹卡尔曼滤波 预览 被引量:4
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作者 黄铫 张天骐 +1 位作者 李越雷 刘燕丽 《电子测量与仪器学报》 CSCD 2009年第S1期56-60,共5页
本文讨论了一种基于扩维的无迹卡尔曼滤波(A-UKF)。通过无迹变换(UT),引出了无迹卡尔曼滤波(UKF)的算法描述,进一步深入研究了扩维无迹卡尔曼滤波,它把非线性系统中的过程噪声和测量噪声引入到采样点中,当采样点通过非线性系统传播时,... 本文讨论了一种基于扩维的无迹卡尔曼滤波(A-UKF)。通过无迹变换(UT),引出了无迹卡尔曼滤波(UKF)的算法描述,进一步深入研究了扩维无迹卡尔曼滤波,它把非线性系统中的过程噪声和测量噪声引入到采样点中,当采样点通过非线性系统传播时,有效的削弱了噪声的影响,并在算法上进行了比较,说明了A-UKF比UKF的精确性要高。最后通过仿真进行了验证。 展开更多
关键词 无迹卡尔曼滤波(UKF) 无迹变换(UT) 扩维(Augmented)
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基于增强型GPS的自适应UKF实时星间相对定位方法 预览 被引量:6
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作者 刘洋 潘晓刚 +1 位作者 王正明 易东云 《测绘学报》 EI CSCD 北大核心 2008年第1期 15-22,29,共9页
高精度的星间实时相对定位是卫星编队飞行的一项关键技术。本文以双星编队为例,提出一种基于GPS双频P码、双频载波相位以及星间距离观测信息的自适应UKF实时相对定位方法。仿真结果表明:相比传统的EKF方法,该算法能有效地提高滤波稳... 高精度的星间实时相对定位是卫星编队飞行的一项关键技术。本文以双星编队为例,提出一种基于GPS双频P码、双频载波相位以及星间距离观测信息的自适应UKF实时相对定位方法。仿真结果表明:相比传统的EKF方法,该算法能有效地提高滤波稳定性及相对定位精度,而且,星间测距信息的引入能大大减少整周模糊度判定所需的历元数。 展开更多
关键词 编队飞行 实时相对定位 增强型 双频GPS 自适应UKF
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光学透视式增强现实显示系统虚实遮挡问题研究 预览 被引量:3
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作者 王红 周雅 +1 位作者 马晋涛 刘宪鹏 《中国图象图形学报》 CSCD 北大核心 2008年第8期 1566-1569,共4页
鉴于增强现实系统中,虚拟物体与真实环境之间是否具有正确的遮挡关系会影响到虚实融合能否取得逼真的效果,为此根据一种新型光学透视式头盔显示器,提出了一种利用OpenGL来绘制虚拟网格遮挡平面,以便使虚拟物体呈现被裁剪的形态,而... 鉴于增强现实系统中,虚拟物体与真实环境之间是否具有正确的遮挡关系会影响到虚实融合能否取得逼真的效果,为此根据一种新型光学透视式头盔显示器,提出了一种利用OpenGL来绘制虚拟网格遮挡平面,以便使虚拟物体呈现被裁剪的形态,而与真实物体融合后可呈现出实挡虚效果的方法。这种方法,在程序实现方面相对较为容易,且计算量较低,因而更适宜实时系统的使用。通过实验可以看出,采用OpenGL对虚拟物体与真实场景的深度数组进行逐点深度比较来绘制遮挡平面的方法是可行的。 展开更多
关键词 增强现实 光学透视式头盔显示器 虚实遮挡
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