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Novel registration algorithm for 3-D images captured from multiple views of object surface
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作者 衡伟 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期411-413,共3页
A novel algorithm of 3-D surface image registration is proposed. It makes use of the array information of 3-D points and takes vector/vertex-like features as the basis of the matching. That array information of 3-D po... A novel algorithm of 3-D surface image registration is proposed. It makes use of the array information of 3-D points and takes vector/vertex-like features as the basis of the matching. That array information of 3-D points can be easily obtained when capturing original 3-D images. The iterative least-mean-squared (LMS) algorithm is applied to optimizing adaptively the transformation matrix parameters. These can effectively improve the registration performance and hurry up the matching process. Experimental results show that it can reach a good subjective impression on aligned 3-D images. Although the algorithm focuses primarily on the human head model, it can also be used for other objects with small modifications. 展开更多
关键词 image alignment 3-D image 3-D capture image registration iterative least-mean-squared algorithm
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The parallel 3D magnetotelluric forward modeling algorithm 被引量:28
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作者 Tan Handong Tong Tuo Lin Changhong 《Applied Geophysics》 SCIE CSCD 2006年第4期197-202,共6页
The workload of the 3D magnetotelluric forward modeling algorithm is so large that the traditional serial algorithm costs an extremely large compute time. However, the 3D forward modeling algorithm can process the dat... The workload of the 3D magnetotelluric forward modeling algorithm is so large that the traditional serial algorithm costs an extremely large compute time. However, the 3D forward modeling algorithm can process the data in the frequency domain, which is very suitable for parallel computation. With the advantage of MPI and based on an analysis of the flow of the 3D magnetotelluric serial forward algorithm, we suggest the idea of parallel computation and apply it. Three theoretical models are tested and the execution efficiency is compared in different situations. The results indicate that the parallel 3D forward modeling computation is correct and the efficiency is greatly improved. This method is suitable for large size geophysical computations. 展开更多
关键词 Magnetotelluric 3D forward modeling MPI parallel programming design 3D staggered-grid finite difference method parallel algorithm.
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Unfolding analysis of LaBr3:Ce gamma spectrum with a detector response matrix constructing algorithm based on energy resolution calibration 被引量:12
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作者 Rui Shi Xian-Guo Tuo +4 位作者 Huai-Liang Li Yang-Yang Xu Fan-Rong Shi Jian-Bo Yang Yong Luo 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第1期23-31,共9页
With respect to the gamma spectrum, the energy resolution improves with increase in energy. The counts of full energy peak change with energy, and this approximately complies with the Gaussian distribution. This study... With respect to the gamma spectrum, the energy resolution improves with increase in energy. The counts of full energy peak change with energy, and this approximately complies with the Gaussian distribution. This study mainly examines a method to deconvolve the LaBr_3:Ce gamma spectrum with a detector response matrix constructing algorithm based on energy resolution calibration.In the algorithm, the full width at half maximum(FWHM)of full energy peak was calculated by the cubic spline interpolation algorithm and calibrated by a square root of a quadratic function that changes with the energy. Additionally, the detector response matrix was constructed to deconvolve the gamma spectrum. Furthermore, an improved SNIP algorithm was proposed to eliminate the background. In the experiment, several independent peaks of ^(152)Eu,^(137)Cs, and ^(60)Co sources were detected by a LaBr_3:Ce scintillator that were selected to calibrate the energy resolution. The Boosted Gold algorithm was applied to deconvolve the gamma spectrum. The results showed that the peak position difference between the experiment and the deconvolution was within ± 2 channels and the relative error of peak area was approximately within 0.96–6.74%. Finally, a ^(133) Ba spectrum was deconvolved to verify the efficiency and accuracy of the algorithm in unfolding the overlapped peaks. 展开更多
关键词 Detector response MATRIX Energy resolution CALIBRATION LaBr3:Ce scintillator SNIP background elimination Boosted Gold DECONVOLUTION algorithm
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基于LS-SVR的RFID 3D-LANDMARC定位算法 被引量:1
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作者 肖杰 万振刚 《福建电脑》 2018年第5期104-106,共3页
针对当前RFID定位系统的LANDMARC定位算法在三维空间中定位精度不高的问题,提出一种基于LS-SVR的RFID 3D-LANDMARC定位算法。首先采用滑动防脉冲干扰平均滤波的方法对获取到的信号强度指示RSSI值进行滤波预处理,减少环境因素对信号的干... 针对当前RFID定位系统的LANDMARC定位算法在三维空间中定位精度不高的问题,提出一种基于LS-SVR的RFID 3D-LANDMARC定位算法。首先采用滑动防脉冲干扰平均滤波的方法对获取到的信号强度指示RSSI值进行滤波预处理,减少环境因素对信号的干扰。其次,通过SVR算法构建RSSI值与距离之间关系,然后根据LS算法求解出待定位标签的坐标。最后采用误差校正的方法对待定位标签的坐标进行校正。实验结果表明,该算法可有效提高3D-LANDMARC定位精度。 展开更多
关键词 RFID 3d-landmarc RSSI LS-SVR
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Optimization algorithm for rapid 3D gravity inversion 被引量:2
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作者 Jing Lei Yao Chang-Li +3 位作者 Yang Ya-Bin Xu Meng-Long Zhang Guang-Zhi Ji Ruo-Ye 《Applied Geophysics》 SCIE CSCD 2019年第4期507-518,561,共13页
The practical application of 3D inversion of gravity data requires a lot of computation time and storage space.To solve this problem,we present an integrated optimization algorithm with the following components:(1)tar... The practical application of 3D inversion of gravity data requires a lot of computation time and storage space.To solve this problem,we present an integrated optimization algorithm with the following components:(1)targeting high accuracy in the space domain and fast computation in the wavenumber domain,we design a fast 3D forward algorithm with high precision;and(2)taking advantage of the symmetry of the inversion matrix,the main calculation in gravity conjugate gradient inversion is decomposed into two forward calculations,thus optimizing the computational efficiency of 3D gravity inversion.We verify the calculation accuracy and efficiency of the optimization algorithm by testing various grid-number models through numerical simulation experiments. 展开更多
关键词 GRAVITY 3D inversion optimization algorithm high efficiency massive data
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Using MC Algorithm to Implement 3D Image Reconstruction for Yunnan Weather Radar Data 被引量:2
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作者 Zhongneng Liu Zhenzhong Shi +4 位作者 Murong Jiang Jie Zhang Liqing Chen Tian Zhang Gongqin Liu 《Journal of Computer and Communications》 2017年第5期50-61,共12页
3D image reconstruction for weather radar data can not only help the weatherman to improve the forecast efficiency and accuracy, but also help people to understand the weather conditions easily and quickly. Marching C... 3D image reconstruction for weather radar data can not only help the weatherman to improve the forecast efficiency and accuracy, but also help people to understand the weather conditions easily and quickly. Marching Cubes (MC) algorithm in the surface rendering has more excellent applicability in 3D reconstruction for the slice images;it may shorten the time to find and calculate the isosurface from raw volume data, reflect the shape structure more accurately. In this paper, we discuss a method to reconstruct the 3D weather cloud image by using the proposed Cube Weighting Interpolation (CWI) and MC algorithm. Firstly, we detail the steps of CWI, apply it to project the raw radar data into the cubes and obtain the equally spaced cloud slice images, then employ MC algorithm to draw the isosurface. Some experiments show that our method has a good effect and simple operation, which may provide an intuitive and effective reference for realizing the 3D surface reconstruction and meteorological image stereo visualization. 展开更多
关键词 WEATHER RADAR Data 3D Reconstruction MC algorithm CUBE Weighting INTERPOLATION
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Simple Insulin Dose Adjustment Using 3-3-1 Algorithm in Japanese Patients with Type 2 Diabetes: Start Kanazawa Study (Self-Titration Aggressive Algorithm with Glargine Trial) 被引量:1
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作者 Kenji D. Furukawa Naoto Yamaaki +2 位作者 Aya Fujimoto Kiminori Ohyama Hiroaki Muramoto 《Journal of Diabetes Mellitus》 2016年第3期197-203,共7页
We implemented a 3-3-1 algorithm in order to provide safe and simple self-titration in patients who newly initiated BOT as well as who were already on BOT and evaluated its utility in clinical setting. A total of 46 p... We implemented a 3-3-1 algorithm in order to provide safe and simple self-titration in patients who newly initiated BOT as well as who were already on BOT and evaluated its utility in clinical setting. A total of 46 patients, 21 patients in the newly-initiated group and 25 patients in the existing BOT group performed dose adjustment using 3-3-1 algorithm. HbA1c was significantly improved 4 weeks after the initiation from 8.5% ± 1.2% at baseline to 7.3% ± 0.7% at the final evaluation (p  0.01, vs. Baseline). The average daily insulin units increased throughout the study period from 10.1 ± 6.7 at baseline to 14.6 ± 8.9 units at the final evaluation. Weight didn’t significantly change throughout the study (p = 0.12). The incidents of hypoglycemia were 0.8/month during the insulin dose self-adjustment period and 0.4/month during the follow-up period. The 3-3-1 algorithm using insulin glargine provided a safe and simple dose adjustment and demonstrated its utility in patients who were newly introduced to insulin treatment as well as who were already on BOT. 展开更多
关键词 GLARGINE Self-Titration BOT T2DM INSULIN 3-3-1 algorithm
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An improved 3D shape haptic rendering algorithm for finger mounted vibrotactile device 被引量:1
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作者 Wu Juan Han Xiao Yang Huaining 《Journal of Southeast University(English Edition)》 EI CAS 2018年第3期317-322,共6页
To improve the sense of reality on perception, an improved algorithm of 3D shape haptic rendering is put forward based on a finger mounted vibrotactile device. The principle is that the interactive information and the... To improve the sense of reality on perception, an improved algorithm of 3D shape haptic rendering is put forward based on a finger mounted vibrotactile device. The principle is that the interactive information and the shape information are conveyed to users when they touch virtual objects at mobile terminals by attaching the vibrotactile feedback on a fingertip. The extraction of shape characteristics, the interactive information and the mapping of shape in formation of vibration stimulation are key parts of the proposed algorithm to realize the real tactile rendering. The contact status of the interaction process, the height information and local gradient of the touch point are regarded as shape information and used to control the vibration intension, rhythm and distribution of the vibrators. With different contact status and shape information, the vibration pattern can be adjusted in time to imitate the outlines of virtual objects. Finally, the effectiveness of the algorithm is verified by shape perception experiments. The results show that the improved algorithm is effective for 3D shape haptic rendering. 展开更多
关键词 finger mounted vibrotactile device 3D shapehaptic rendering algorithm contact status local gradient
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Improvement of Binocular Reconstruction Algorithm for Measuring 3D Pavement Texture Using a Single Laser Line Scanning Constraint 被引量:1
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作者 Yuanyuan Wang RuiWang +1 位作者 Xiaofeng Ren Junan Lei 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第8期1951-1972,共22页
The dense and accurate measurement of 3D texture is helpful in evaluating the pavement function.To form dense mandatory constraints and improve matching accuracy,the traditional binocular reconstruction technology was... The dense and accurate measurement of 3D texture is helpful in evaluating the pavement function.To form dense mandatory constraints and improve matching accuracy,the traditional binocular reconstruction technology was improved threefold.First,a single moving laser line was introduced to carry out global scanning constraints on the target,which would well overcome the difficulty of installing and recognizing excessive laser lines.Second,four kinds of improved algorithms,namely,disparity replacement,superposition synthesis,subregion segmentation,and subregion segmentation centroid enhancement,were established based on different constraint mechanism.Last,the improved binocular reconstruction test device was developed to realize the dual functions of 3D texture measurement and precision self-evaluation.Results show that compared with traditional algorithms,the introduction of a single laser line scanning constraint is helpful in improving the measurement’s accuracy.Among various improved algorithms,the improvement effect of the subregion segmentation centroid enhancement method is the best.It has a good effect on both overall measurement and single pointmeasurement,which can be considered to be used in pavement function evaluation. 展开更多
关键词 3D pavement texture binocular reconstruction algorithm single laser line scanning constraint improved stereo matching
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Adaptive Window Based 3-D Feature Selection for Multispectral Image Classification Using Firefly Algorithm 被引量:1
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作者 M.Rajakani R.J.Kavitha A.Ramachandran 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期265-280,共16页
Feature extraction is the most critical step in classification of multispectral image.The classification accuracy is mainly influenced by the feature sets that are selected to classify the image.In the past,handcrafte... Feature extraction is the most critical step in classification of multispectral image.The classification accuracy is mainly influenced by the feature sets that are selected to classify the image.In the past,handcrafted feature sets are used which are not adaptive for different image domains.To overcome this,an evolu-tionary learning method is developed to automatically learn the spatial-spectral features for classification.A modified Firefly Algorithm(FA)which achieves maximum classification accuracy with reduced size of feature set is proposed to gain the interest of feature selection for this purpose.For extracting the most effi-cient features from the data set,we have used 3-D discrete wavelet transform which decompose the multispectral image in all three dimensions.For selecting spatial and spectral features we have studied three different approaches namely overlapping window(OW-3DFS),non-overlapping window(NW-3DFS)adaptive window cube(AW-3DFS)and Pixel based technique.Fivefold Multiclass Support Vector Machine(MSVM)is used for classification purpose.Experiments con-ducted on Madurai LISS IV multispectral image exploited that the adaptive win-dow approach is used to increase the classification accuracy. 展开更多
关键词 Multispectral image modifiedfirefly algorithm 3-D feature extraction feature selection multiclass support vector machine CLASSIFICATION
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Adaptive tracking algorithm based on 3D variable turn model 被引量:1
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作者 Xiaohua Nie Fuming Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第5期851-860,共10页
Satisfactory results cannot be obtained when three-dimensional (3D) targets with complex maneuvering characteristics are tracked by the commonly used two-dimensional coordinated turn (2DCT) model. To address the probl... Satisfactory results cannot be obtained when three-dimensional (3D) targets with complex maneuvering characteristics are tracked by the commonly used two-dimensional coordinated turn (2DCT) model. To address the problem of 3D target tracking with strong maneuverability, on the basis of the modified three-dimensional variable turn (3DVT) model, an adaptive tracking algorithm is proposed by combining with the cubature Kalman filter (CKF) in this paper. Through ideology of real-time identification, the parameters of the model are changed to adjust the state transition matrix and the state noise covariance matrix. Therefore, states of the target are matched in real-time to achieve the purpose of adaptive tracking. Finally, four simulations are analyzed in different settings by the Monte Carlo method. All results show that the proposed algorithm can update parameters of the model and identify motion characteristics in real-time when targets tracking also has a better tracking accuracy. 展开更多
关键词 maneuvering target tracking adaptive tracking algorithm modified three-dimensional variable turn (3DVT) model cubature Kalman filter (CKF)
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Estimation of Crop Biomass Using GF-3 Polarization SAR Data Based on Genetic Algorithm Feature Selection 被引量:5
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作者 Kunpeng XU Lei ZHAO +3 位作者 Kun LI Erxue CHEN Wangfei ZHANG Hao YANG 《Journal of Geodesy and Geoinformation Science》 2020年第4期126-136,共11页
In recent years,Polarization SAR(PolSAR)has been widely used in the filed of crop biomass estimation.However,high dimensional features extracted from PolSAR data will lead to information redundancy which will result i... In recent years,Polarization SAR(PolSAR)has been widely used in the filed of crop biomass estimation.However,high dimensional features extracted from PolSAR data will lead to information redundancy which will result in low accuracy and poor transfer ability of the estimation model.Aiming at this problem,we proposed a estimation method of crop biomass based on automatic feature selection method using genetic algorithm(GA).Firstly,the backscattering coefficient,the polarization parameters and texture features were extracted from PolSAR data.Then,these features were automatically pre-selected by GA to obtain the optimal feature subset.Finally,based on this subset,a support vector regression machine(SVR)model was applied to estimate crop biomass.The proposed method was validated using the GaoFen-3(GF-3)QPSΙ(C-band,quad-polarization)SAR data.Based on wheat and rape biomass samples acquired from a synchronous field measurement campaign,the proposed method achieve relative high validation accuracy(over 80%)in both crop types.For further analyzing the improvement of proposed method,validation accuracies of biomass estimation models based on several different feature selection methods were compared.Compared with feature selection based on linear correlation,GA method has increased by 5.77%in wheat biomass estimation and 11.84%in rape biomass estimation.Compared with the method of recursive feature elimination(RFE)selection,the proposed method has improved crops biomass estimation accuracy by 3.90%and 5.21%,respectively. 展开更多
关键词 Polarization SAR estimation of crop biomass genetic algorithm feature selection GaoFen-3
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Generating Decision Trees Method Based on Improved ID3 Algorithm
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作者 杨明 郭树旭 王隽 《China Communications》 SCIE CSCD 2011年第5期151-156,共6页
The ID3 algorithm is a classical learning algorithm of decision tree in data mining.The algorithm trends to choosing the attribute with more values,affect the efficiency of classification and prediction for building a... The ID3 algorithm is a classical learning algorithm of decision tree in data mining.The algorithm trends to choosing the attribute with more values,affect the efficiency of classification and prediction for building a decision tree.This article proposes a new approach based on an improved ID3 algorithm.The new algorithm introduces the importance factor λ when calculating the information entropy.It can strengthen the label of important attributes of a tree and reduce the label of non-important attributes.The algorithm overcomes the flaw of the traditional ID3 algorithm which tends to choose the attributes with more values,and also improves the efficiency and flexibility in the process of generating decision trees. 展开更多
关键词 decision tree ID3 algorithm importance factor attribute value
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A New 3D Wireless Directional Sensing Model and Coverage Enhancement Algorithm
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作者 Xiaojun Bi Pengfei Diao 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第1期41-45,共5页
Coverage control for each sensor is based on a 2D directional sensing model in directional sensor networks conventionally. But the 2D model cannot accurately characterize the real environment. In order to solve this p... Coverage control for each sensor is based on a 2D directional sensing model in directional sensor networks conventionally. But the 2D model cannot accurately characterize the real environment. In order to solve this problem,a new 3D directional sensor model and coverage enhancement algorithm is proposed. We can adjust the pitch angle and deviation angle to enhance the coverage rate. And the coverage enhancement algorithm is based on an improved gravitational search algorithm. In this paper the two improved strategies of GSA are directional mutation strategy and individual evolution strategy. A set of simulations show that our coverage enhancement algorithm has a good performance to improve the coverage rate of the wireless directional sensor network on different number of nodes,different virtual angles and different sensing radius. 展开更多
关键词 3D WIRELESS directional sensor network COVERAGE ENHANCEMENT GRAVITATIONAL SEARCH algorithm
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Fragile Watermarking of 3D Models Using Genetic Algorithms
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作者 Mukesh Motwani Rakhi Motwani Frederick Harris 《Journal of Electronic Science and Technology》 CAS 2010年第3期244-250,共7页
This paper describes a novel algorithm for fragile watermarking of 3D models. Fragile watermarking requires detection of even minute intentional changes to the 3D model along with the location of the change. This pose... This paper describes a novel algorithm for fragile watermarking of 3D models. Fragile watermarking requires detection of even minute intentional changes to the 3D model along with the location of the change. This poses a challenge since inserting random amount of watermark in all the vertices of the model would generally introduce perceptible distortion. The proposed algorithm overcomes this challenge by using genetic algorithm to modify every vertex location in the model so that there is no perceptible distortion. Various experimental results are used to justify the choice of the genetic algorithm design parameters. Experimental results also indicate that the proposed algorithm can accurately detect location of any mesh modification. 展开更多
关键词 3D mesh models fragile water- marking genetic algorithms SNR.
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A Study on Parallel Computation Based on 3D Forward Algorithm of Gravity
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作者 Mao Wang Yuanman Zheng Changli Yao 《International Journal of Geosciences》 2017年第9期1073-1079,共7页
Interpretation of geophysical material is the prospecting method. Interpretation of Gravity-megnetic data is based on data processing and inversion. When the grid is divided into several million cells, the computing t... Interpretation of geophysical material is the prospecting method. Interpretation of Gravity-megnetic data is based on data processing and inversion. When the grid is divided into several million cells, the computing task is heavy and time-consuming. In order to increase efficiency of the 3D forward modeling, the paper will adopt MPI parallel algorithm and the several processes will deal with data in the method. Finally, we can gather the result. Through comparing the result of sequence algorithm with the result of MPI parallel algorithm, we can see the result is the same. When the number of processes is 2 to 8, the speed-up ratio is 1.97 to 5. The MPI parallel algorithm is very efficient. 展开更多
关键词 GRAVITY 3D FORWARD MODELING PARALLEL algorithm MPI
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Research on a bifurcation location algorithm of a drainage tube based on 3D medical images
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作者 Qiuling Pan Wei Zhu +2 位作者 Xiaolin Zhang Jincai Chang Jianzhong Cui 《Visual Computing for Industry,Biomedicine,and Art》 2020年第1期7-17,共11页
Based on patient computerized tomography data,we segmented a region containing an intracranial hematoma using the threshold method and reconstructed the 3D hematoma model.To improve the efficiency and accuracy of iden... Based on patient computerized tomography data,we segmented a region containing an intracranial hematoma using the threshold method and reconstructed the 3D hematoma model.To improve the efficiency and accuracy of identifying puncture points,a point-cloud search arithmetic method for modified adaptive weighted particle swarm optimization is proposed and used for optimal external axis extraction.According to the characteristics of the multitube drainage tube and the clinical needs of puncture for intracranial hematoma removal,the proposed algorithm can provide an optimal route for a drainage tube for the hematoma,the precise position of the puncture point,and preoperative planning information,which have considerable instructional significance for clinicians. 展开更多
关键词 Multitube drainage tube Bifurcation localization algorithm 3D medical image Path planning Intracranial hematoma
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An improved bicubic imaging fitting algorithm for 3D radar detection target
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作者 Li Fan-Ruo Yang Feng +3 位作者 Yan Rui Qiao Xu Li Yi-Jin Xing Hong-Jia 《Applied Geophysics》 SCIE CSCD 2022年第4期553-562,604,共11页
3D ground-penetrating radar has been widely used in urban road underground disease detection due to its nondestructive,efficient,and intuitive results.However,the 3D imaging of the underground target body presents the... 3D ground-penetrating radar has been widely used in urban road underground disease detection due to its nondestructive,efficient,and intuitive results.However,the 3D imaging of the underground target body presents the edge plate phenomenon due to the space between the 3D radar array antennas.Consequently,direct 3D imaging using detection results cannot reflect underground spatial distribution characteristics.Due to the wide-beam polarization of the ground-penetrating radar antenna,the emission of electromagnetic waves with a specific width decreases the strong middle energy on both sides gradually.Therefore,a bicubic high-precision 3D target body slice-imaging fitting algorithm with changing trend characteristics is constructed by combining the subsurface target characteristics with the changing spatial morphology trends.Using the wide-angle polarization antenna’s characteristics in the algorithm to build the trend factor between the measurement lines,the target body change trend and the edge detail portrayal achieve a 3D ground-penetrating radar-detection target high-precision fitting.Compared with other traditional fitting techniques,the fitting error is small.This paper conducts experiments and analyses on GpaMax 3D forward modeling and 3D ground-penetrating measured radar data.The experiments show that the improved bicubic fitting algorithm can eff ectively improve the accuracy of underground target slice imaging and the 3D ground-penetrating radar’s anomaly interpretation. 展开更多
关键词 urban underground space safety 3D ground-penetrating radar detection of the abnormal bicubic fitting algorithm high-precision imaging
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A New Three-Dimensional(3D)Printing Prepress Algorithm for Simulation of Planned Surgery for Congenital Heart Disease
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作者 Vitaliy Suvorov Olga Loboda +1 位作者 Maria Balakina Igor Kulczycki 《Congenital Heart Disease》 SCIE 2023年第5期491-505,共15页
Background:Three-dimensional printing technology may become a key factor in transforming clinical practice and in significant improvement of treatment outcomes.The introduction of this technique into pediatric cardiac... Background:Three-dimensional printing technology may become a key factor in transforming clinical practice and in significant improvement of treatment outcomes.The introduction of this technique into pediatric cardiac surgery will allow us to study features of the anatomy and spatial relations of a defect and to simulate the optimal surgical repair on a printed model in every individual case.Methods:We performed the prospective cohort study which included 29 children with congenital heart defects.The hearts and the great vessels were modeled and printed out.Measurements of the same cardiac areas were taken in the same planes and points at multislice computed tomography images(group 1)and on printed 3D models of the hearts(group 2).Pre-printing treatment of the multislice computed tomography data and 3D model preparation were performed according to a newly developed algorithm.Results:The measurements taken on the 3D-printed cardiac models and the tomographic images did not differ significantly,which allowed us to conclude that the models were highly accurate and informative.The new algorithm greatly simplifies and speeds up the preparation of a 3D model for printing,while maintaining high accuracy and level of detail.Conclusions:The 3D-printed models provide an accurate preoperative assessment of the anatomy of a defect in each case.The new algorithm has several important advantages over other available programs.They enable the development of customized preliminary plans for surgical repair of each specific complex congenital heart disease,predict possible issues,determine the optimal surgical tactics,and significantly improve surgical outcomes. 展开更多
关键词 3D printing imaging in cardiac surgery congenital heart disease modelling in cardiac surgery pediatric cardiology algorithmic modelling of the heart medical imaging 3D modelling
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RP-3航空煤油/O_(2)的简化反应机理优化与验证
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作者 曾文 徐紫馨 +2 位作者 张鑫炜 胡斌 常亚超 《燃烧科学与技术》 CAS CSCD 北大核心 2024年第6期539-549,共11页
采用RP-3航空煤油的简化反应机理对多工况条件下RP-3航空煤油/氧气混合物的氧化、着火延迟与层流燃烧特性进行了数值计算,并与相应试验数据进行了对比验证;同时,采用敏感性分析方法对该简化反应机理中燃料相关骨架反应机理中的基元反应... 采用RP-3航空煤油的简化反应机理对多工况条件下RP-3航空煤油/氧气混合物的氧化、着火延迟与层流燃烧特性进行了数值计算,并与相应试验数据进行了对比验证;同时,采用敏感性分析方法对该简化反应机理中燃料相关骨架反应机理中的基元反应进行了敏感性分析;采用遗传算法,对重要的基元反应速率常数进行优化,形成了优化后的RP-3航空煤油/氧气混合物的简化反应机理.结果表明,大部分工况条件下初始简化反应机理对RP-3航空煤油/氧气混合物氧化过程中主要组分浓度、着火延迟时间以及层流燃烧速度的预测值与相应试验值存在较大误差.同时,优化后的简化反应机理对多工况条件下RP-3航空煤油/氧气混合物氧化过程中的主要组分浓度、着火延迟时间及层流燃烧速度的预测值与相应试验值吻合较好. 展开更多
关键词 RP-3航空煤油 简化反应机理 敏感性分析 遗传算法 燃烧特性
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