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PREPROCESSING AND POSTPROCESSING SYSTEM FOR FINITE ELEMENT COMPUTATION
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作者 李俊 潘梅园 陈钟鸣 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1998年第2期108-112,共5页
This paper discusses some aspects of finite element computation,such as the automatic generation of finite element ,refinement of mesh,process of node density, distribution of load,optimum design and the drawing o... This paper discusses some aspects of finite element computation,such as the automatic generation of finite element ,refinement of mesh,process of node density, distribution of load,optimum design and the drawing of stress contour, and describes the developing process of software for a planar 8 node element. 展开更多
关键词 finite element method optimum design stress CONTOUR preprocessing and post processing load distribution
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Adaptive preprocessing algorithms of corneal topography in polar coordinate system 被引量:1
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作者 郭雁文 《Journal of Central South University》 SCIE EI CAS 2014年第12期4571-4576,共6页
New adaptive preprocessing algorithms based on the polar coordinate system were put forward to get high-precision corneal topography calculation results. Adaptive locating algorithms of concentric circle center were c... New adaptive preprocessing algorithms based on the polar coordinate system were put forward to get high-precision corneal topography calculation results. Adaptive locating algorithms of concentric circle center were created to accurately capture the circle center of original Placido-based image, expand the image into matrix centered around the circle center, and convert the matrix into the polar coordinate system with the circle center as pole. Adaptive image smoothing treatment was followed and the characteristics of useful circles were extracted via horizontal edge detection, based on useful circles presenting approximate horizontal lines while noise signals presenting vertical lines or different angles. Effective combination of different operators of morphology were designed to remedy data loss caused by noise disturbances, get complete image about circle edge detection to satisfy the requests of precise calculation on follow-up parameters. The experimental data show that the algorithms meet the requirements of practical detection with characteristics of less data loss, higher data accuracy and easier availability. 展开更多
关键词 corneal topography Placido disk polar coordinate self-adoption preprocessing algorithms
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Effect of preprocessing on performances of machine learning-based mineral composition analysis on gas hydrate sediments,Ulleung Basin,East Sea 被引量:1
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作者 Hongkeun Jin Ju Young Park +3 位作者 Sun Young Park Byeong-Kook Son Baehyun Min Kyungbook Lee 《Petroleum Science》 2025年第1期151-162,共12页
Gas hydrate(GH)is an unconventional resource estimated at 1000-120,000 trillion m^(3)worldwide.Research on GH is ongoing to determine its geological and flow characteristics for commercial produc-tion.After two large-... Gas hydrate(GH)is an unconventional resource estimated at 1000-120,000 trillion m^(3)worldwide.Research on GH is ongoing to determine its geological and flow characteristics for commercial produc-tion.After two large-scale drilling expeditions to study the GH-bearing zone in the Ulleung Basin,the mineral composition of 488 sediment samples was analyzed using X-ray diffraction(XRD).Because the analysis is costly and dependent on experts,a machine learning model was developed to predict the mineral composition using XRD intensity profiles as input data.However,the model’s performance was limited because of improper preprocessing of the intensity profile.Because preprocessing was applied to each feature,the intensity trend was not preserved even though this factor is the most important when analyzing mineral composition.In this study,the profile was preprocessed for each sample using min-max scaling because relative intensity is critical for mineral analysis.For 49 test data among the 488 data,the convolutional neural network(CNN)model improved the average absolute error and coefficient of determination by 41%and 46%,respectively,than those of CNN model with feature-based pre-processing.This study confirms that combining preprocessing for each sample with CNN is the most efficient approach for analyzing XRD data.The developed model can be used for the compositional analysis of sediment samples from the Ulleung Basin and the Korea Plateau.In addition,the overall procedure can be applied to any XRD data of sediments worldwide. 展开更多
关键词 Sample-based preprocessing X-ray diffraction(XRD) Machine learning Mineral composition Gas hydrate(GH) Ulleung basin
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Hybrid Teaching Reform and Practice in Big Data Collection and Preprocessing Courses Based on the Bosi Smart Learning Platform 被引量:1
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作者 Yang Wang Xuemei Wang Wanyan Wang 《Journal of Contemporary Educational Research》 2025年第2期96-100,共5页
This study examines the Big Data Collection and Preprocessing course at Anhui Institute of Information Engineering,implementing a hybrid teaching reform using the Bosi Smart Learning Platform.The proposed hybrid model... This study examines the Big Data Collection and Preprocessing course at Anhui Institute of Information Engineering,implementing a hybrid teaching reform using the Bosi Smart Learning Platform.The proposed hybrid model follows a“three-stage”and“two-subject”framework,incorporating a structured design for teaching content and assessment methods before,during,and after class.Practical results indicate that this approach significantly enhances teaching effectiveness and improves students’learning autonomy. 展开更多
关键词 Big Data Collection and preprocessing Bosi smart learning platform Hybrid teaching Teaching reform
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Swiftly accessible retinomorphic hardware for in-sensor image preprocessing and recognition:IGZO-based neuro-inspired optical image sensor arrays with metallic sensitization island
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作者 Kyungmoon Kwak Kyungho Park +7 位作者 Jae Seong Han Byung Ha Kang Dong Hyun Choi Kunho Moon Seok Min Hong Gwan In Kim Ju Hyun Lee Hyun Jae Kim 《International Journal of Extreme Manufacturing》 2025年第6期494-510,共17页
In-optical-sensor computing architectures based on neuro-inspired optical sensor arrays have become key milestones for in-sensor artificial intelligence(AI)technology,enabling intelligent vision sensing and extensive ... In-optical-sensor computing architectures based on neuro-inspired optical sensor arrays have become key milestones for in-sensor artificial intelligence(AI)technology,enabling intelligent vision sensing and extensive data processing.These architectures must demonstrate potential advantages in terms of mass production and complementary metal oxide semiconductor compatibility.Here,we introduce a visible-light-driven neuromorphic vision system that integrates front-end retinomorphic photosensors with a back-end artificial neural network(ANN),employing a single neuro-inspired indium-g allium-zinc-oxide photo transistor(NIP)featuring an aluminum sensitization layer(ASL).By methodically adjusting the ASL coverage on IGZO phototransistors,a fast-switching response-type and a synaptic response-type of IGZO photo transistors are successfully developed.Notably,the fabricated NIP shows a remarkable retina-like photoinduced synaptic plasticity under wavelengths up to 635 nm,with over256-states,weight update nonlinearity below 0.1,and a dynamic range of 64.01.Owing to this technology,a 6×6 neuro-inspired optical image sensor array with the NIP can perform highly integrated sensing,memory,and preprocessing functions,including contrast enhancement,and handwritten digit image recognition.The demonstrated prototype highlights the potential for efficient hardware implementations in in-sensor AI technologies. 展开更多
关键词 retinomorphic hardware in-sensor preprocessing image recognition neuro-inspired optical sensors indium-gallium-zinc-oxide metallic sensitization layer
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TBM big data preprocessing method in machine learning and its application to tunneling
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作者 Xinyue Zhang Xiaoping Zhang +3 位作者 Quansheng Liu Weiqiang Xie Shaohui Tang Zengmao Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第8期4762-4783,共22页
The big data generated by tunnel boring machines(TBMs)are widely used to reveal complex rock-machine interactions by machine learning(ML)algorithms.Data preprocessing plays a crucial role in improving ML accuracy.For ... The big data generated by tunnel boring machines(TBMs)are widely used to reveal complex rock-machine interactions by machine learning(ML)algorithms.Data preprocessing plays a crucial role in improving ML accuracy.For this,a TBM big data preprocessing method in ML was proposed in the present study.It emphasized the accurate division of TBM tunneling cycle and the optimization method of feature extraction.Based on the data collected from a TBM water conveyance tunnel in China,its effectiveness was demonstrated by application in predicting TBM performance.Firstly,the Score-Kneedle(S-K)method was proposed to divide a TBM tunneling cycle into five phases.Conducted on 500 TBM tunneling cycles,the S-K method accurately divided all five phases in 458 cycles(accuracy of 91.6%),which is superior to the conventional duration division method(accuracy of 74.2%).Additionally,the S-K method accurately divided the stable phase in 493 cycles(accuracy of 98.6%),which is superior to two state-of-the-art division methods,namely the histogram discriminant method(accuracy of 94.6%)and the cumulative sum change point detection method(accuracy of 92.8%).Secondly,features were extracted from the divided phases.Specifically,TBM tunneling resistances were extracted from the free rotating phase and free advancing phase.The resistances were subtracted from the total forces to represent the true rock-fragmentation forces.The secant slope and the mean value were extracted as features of the increasing phase and stable phase,respectively.Finally,an ML model integrating a deep neural network and genetic algorithm(GA-DNN)was established to learn the preprocessed data.The GA-DNN used 6 secant slope features extracted from the increasing phase to predict the mean field penetration index(FPI)and torque penetration index(TPI)in the stable phase,guiding TBM drivers to make better decisions in advance.The results indicate that the proposed TBM big data preprocessing method can improve prediction accuracy significantly(improving R2s of TPI and FPI on the test dataset from 0.7716 to 0.9178 and from 0.7479 to 0.8842,respectively). 展开更多
关键词 Tunnel boring machine Big data preprocessing Division of tunneling cycle Tunneling resistance Machine learning
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The Application of Machine Vision in Defect Detection Systems
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作者 Peihang Zhong Jiawei Lin Muling Wang 《Journal of Electronic Research and Application》 2025年第2期191-196,共6页
With the rapid development of computer vision technology,artificial intelligence algorithms,and high-performance computing platforms,machine vision technology has gradually shown its great potential in automated produ... With the rapid development of computer vision technology,artificial intelligence algorithms,and high-performance computing platforms,machine vision technology has gradually shown its great potential in automated production lines,especially in defect detection.Machine vision technology can be applied in many industries such as semiconductor,automobile manufacturing,aerospace,food,and drugs,which can significantly improve detection efficiency and accuracy,reduce labor costs,improve product quality,enhance market competitiveness,and provide strong support for the arrival of Industry 4.0 era.In this article,the concept,advantages,and disadvantages of machine vision and the algorithm framework of machine vision in the defect detection system are briefly described,aiming to promote the rapid development of industry and strengthen China’s industry. 展开更多
关键词 Machine vision Defect detection system Image preprocessing
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Screening of Preprocessing Method of Biolog for Soil Microbial Community Functional Diversity 被引量:2
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作者 党雯 郜春花 +4 位作者 张强 李建华 卢朝东 靳东升 卢晋晶 《Agricultural Science & Technology》 CAS 2015年第10期2247-2251,2255,共6页
As one of the main methods of microbial community functional diversity measurement, biolog method was favored by many researchers for its simple oper- ation, high sensitivity, strong resolution and rich data. But the ... As one of the main methods of microbial community functional diversity measurement, biolog method was favored by many researchers for its simple oper- ation, high sensitivity, strong resolution and rich data. But the preprocessing meth- ods reported in the literatures were not the same. In order to screen the best pre- processing method, this paper took three typical treatments to explore the effect of different preprocessing methods on soil microbial community functional diversity. The results showed that, method B's overall trend of AWCD values was better than A and C's. Method B's microbial utilization of six carbon sources was higher, and the result was relatively stable. The Simpson index, Shannon richness index and Car- bon source utilization richness index of the two treatments were B〉C〉A, while the Mclntosh index and Shannon evenness were not very stable, but the difference of variance analysis was not significant, and the method B was always with a smallest variance. Method B's principal component analysis was better than A and C's. In a word, the method using 250 r/min shaking for 30 minutes and cultivating at 28 ℃ was the best one, because it was simple, convenient, and with good repeatability. 展开更多
关键词 Biolog method preprocessing method Soil microbial community Func- tional diversity AWCD values
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Collaborative Area Coverage Method for UAV Swarm Under Complex Boundary Conditions:A Region Partitioning Approach
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作者 Jiabin Yu Haocun Wang +4 位作者 Bingyi Wang Yang Lu Xin Zhang Qian Sun Zhiyao Zhao 《Journal of Bionic Engineering》 2026年第1期524-548,共25页
Unmanned aerial vehicles(UAVs)are widely utilized in area coverage tasks due to their flexibility and efficiency in geo-graphic information acquisition.However,complex boundary conditions in actual water area maps oft... Unmanned aerial vehicles(UAVs)are widely utilized in area coverage tasks due to their flexibility and efficiency in geo-graphic information acquisition.However,complex boundary conditions in actual water area maps often reduce coverage efficiency.To address this issue,this paper proposes a map preprocessing algorithm that linearizes boundary lines and processes concave areas into concave polygons,followed by gridding the map.Additionally,a collaborative area coverage method for UAV swarms is introduced based on region partitioning,which considers the comprehensive cost of energy consumption and time.An improved Hungarian algorithm is utilized for region partitioning,and a Dubins-A*-based plow-ing area full coverage path planning method is proposed to achieve path smoothing and collaborative coverage of each partition.Two sets of simulation experiments are conducted.The first experiment verifies the effectiveness of the map preprocessing algorithm,and the second compares the proposed collaborative area coverage algorithm with other methods,demonstrating its performance advantages. 展开更多
关键词 Complex boundaries UAV swarm Collaborative area coverage Map preprocessing Region partitioning
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A Systematic Review on the Internet of Medical Things:Techniques,Open Issues,and Future Directions 被引量:3
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作者 Apurva Sonavane Aditya Khamparia Deepak Gupta 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第11期1525-1550,共26页
IoT usage in healthcare is one of the fastest growing domains all over the world which applies to every age group.Internet of Medical Things(IoMT)bridges the gap between the medical and IoT field where medical devices... IoT usage in healthcare is one of the fastest growing domains all over the world which applies to every age group.Internet of Medical Things(IoMT)bridges the gap between the medical and IoT field where medical devices communicate with each other through a wireless communication network.Advancement in IoMT makes human lives easy and better.This paper provides a comprehensive detailed literature survey to investigate different IoMT-driven applications,methodologies,and techniques to ensure the sustainability of IoMT-driven systems.The limitations of existing IoMTframeworks are also analyzed concerning their applicability in real-time driven systems or applications.In addition to this,various issues(gaps),challenges,and needs in the context of such systems are highlighted.The purpose of this paper is to interpret a rigorous review concept related to IoMT and present significant contributions in the field across the research fraternity.Lastly,this paper discusses the opportunities and prospects of IoMT and discusses various open research problems. 展开更多
关键词 Internet ofMedical Things(IoMT) healthcare systems sensors preprocessing RFID remote monitoring devices networks
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Land 3D-Seismic Data: Preprocessing Quality Control Utilizing Survey Design Specifications, Noise Properties, Normal Moveout, First Breaks, and Offset 被引量:2
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作者 Abdelmoneam Raef 《Journal of China University of Geosciences》 SCIE CSCD 2009年第3期640-648,共9页
The recent proliferation of the 3D reflection seismic method into the near-surface area of geophysical applications, especially in response to the emergence of the need to comprehensively characterize and monitor near... The recent proliferation of the 3D reflection seismic method into the near-surface area of geophysical applications, especially in response to the emergence of the need to comprehensively characterize and monitor near-surface carbon dioxide sequestration in shallow saline aquifers around the world, justifies the emphasis on cost-effective and robust quality control and assurance (QC/QA) workflow of 3D seismic data preprocessing that is suitable for near-surface applications. The main purpose of our seismic data preprocessing QC is to enable the use of appropriate header information, data that are free of noise-dominated traces, and/or flawed vertical stacking in subsequent processing steps. In this article, I provide an account of utilizing survey design specifications, noise properties, first breaks, and normal moveout for rapid and thorough graphical QC/QA diagnostics, which are easy to apply and efficient in the diagnosis of inconsistencies. A correlated vibroseis time-lapse 3D-seismic data set from a CO2-flood monitoring survey is used for demonstrating QC diagnostics. An important by-product of the QC workflow is establishing the number of layers for a refraction statics model in a data-driven graphical manner that capitalizes on the spatial coverage of the 3D seismic data. 展开更多
关键词 preprocessing quality control 3D seismic 4D seismic trace header geometry vertical stacking.
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Implementation System of Human Eye Tracking Algorithm Based on FPGA 被引量:2
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作者 Zhong Liu Xin’an Wang +1 位作者 Chengjun Sun Ken Lu 《Computers, Materials & Continua》 SCIE EI 2019年第3期653-664,共12页
With the high-speed development of transportation industry,highway traffic safety has become a considerable problem.Meanwhile,with the development of embedded system and hardware chip,in recent years,human eye detecti... With the high-speed development of transportation industry,highway traffic safety has become a considerable problem.Meanwhile,with the development of embedded system and hardware chip,in recent years,human eye detection eye tracking and positioning technology have been more and more widely used in man-machine interaction,security access control and visual detection.In this paper,the high parallelism of FPGA was utilized to realize an elliptical approximate real-time human eye tracking system,which was achieved by the series register structure and random sample consensus(RANSAC),thus improving the speed of image processing without using external memory.Because eye images acquired by the camera often generate a lot of noises due to uneven light and dark background,the preprocessing technologies such as color conversion,image filtering,histogram modification and image sharpening were adopted.In terms of feature extraction of images,the eye tracking algorithm in this paper adopted seven-section rectangular eye tracking characteristic method,which increased a section between the mouth and the nose on the basis of the traditional six-section method,so its recognition accuracy is much higher.It is convenient for the realization of hardware parallel system in FPGA.Finally,aiming at the accuracy and real-time performance of the design system,a more comprehensive simulation test was carried out.The human eye tracking system was verified on DE2-115 multimedia development platform,and the performance of VGA(resolution:640×480)images of 8-bit grayscale was tested.The results showed that the detection speed of this system was about 47 frames per second under the condition that the detection rate of human face(front face,no inclination)was 93%,which reached the real-time detection level.Additionally,the accuracy of eye tracking based on FPGA system was more than 95%,and it has achieved ideal results in real-time performance and robustness. 展开更多
关键词 Human eye tracking FPGA real-time performance preprocessing elliptic approximation.
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Power Data Preprocessing Method of Mountain Wind Farm Based on POT-DBSCAN 被引量:2
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作者 Anfeng Zhu Zhao Xiao Qiancheng Zhao 《Energy Engineering》 EI 2021年第3期549-563,共15页
Due to the frequent changes of wind speed and wind direction,the accuracy of wind turbine(WT)power prediction using traditional data preprocessing method is low.This paper proposes a data preprocessing method which co... Due to the frequent changes of wind speed and wind direction,the accuracy of wind turbine(WT)power prediction using traditional data preprocessing method is low.This paper proposes a data preprocessing method which combines POT with DBSCAN(POT-DBSCAN)to improve the prediction efficiency of wind power prediction model.Firstly,according to the data of WT in the normal operation condition,the power prediction model ofWT is established based on the Particle Swarm Optimization(PSO)Arithmetic which is combined with the BP Neural Network(PSO-BP).Secondly,the wind-power data obtained from the supervisory control and data acquisition(SCADA)system is preprocessed by the POT-DBSCAN method.Then,the power prediction of the preprocessed data is carried out by PSO-BP model.Finally,the necessity of preprocessing is verified by the indexes.This case analysis shows that the prediction result of POT-DBSCAN preprocessing is better than that of the Quartile method.Therefore,the accuracy of data and prediction model can be improved by using this method. 展开更多
关键词 Wind turbine SCADA data data preprocessing method power prediction
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Improvement and application of preprocessing technique for multitrace seismic impedance inversion 被引量:1
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作者 Zhong Fei-Yan Zhou Lu +3 位作者 Dai Rong-Huo Yin Cheng Zhao Hu Xu Liang-Jun 《Applied Geophysics》 SCIE CSCD 2021年第1期54-62,129,共10页
The conventional poststack inversion uses standard recursion formulas to obtain impedance in a single trace.It cannot allow for lateral regularization.In this paper,ID edge-preserving smoothing(EPS)fi lter is extended... The conventional poststack inversion uses standard recursion formulas to obtain impedance in a single trace.It cannot allow for lateral regularization.In this paper,ID edge-preserving smoothing(EPS)fi lter is extended to 2D/3D for setting precondition of impedance model in impedance inversion.The EPS filter incorporates a priori knowledge into the seismic inversion.The a priori knowledge incorporated from EPS filter preconditioning relates to the blocky features of the impedance model,which makes the formation interfaces and geological edges precise and keeps the inversion procedure robust.Then,the proposed method is performed on two 2D models to show its feasibility and stability.Last,the proposed method is performed on a real 3D seismic work area from Southwest China to predict reef reservoirs in practice. 展开更多
关键词 Multitrace impedance inversion edge-preserving smoothing preprocessing of inversion reef reservoirs
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Data preprocessing and preliminary results of the Moon-based Ultraviolet Telescope on the CE-3 lander 被引量:4
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作者 Wei-Bin Wen Fang Wang +8 位作者 Chun-Lai Li Jing Wang Li Cao Jian-Jun Liu Xu Tan Yuan Xiao Qiang Fu Yan Su Wei Zuo 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1674-1681,共8页
The Moon-based Ultraviolet Telescope (MUVT) is one of the payloads on the Chang'e-3 (CE-3) lunar lander. Because of the advantages of having no at- mospheric disturbances and the slow rotation of the Moon, we can... The Moon-based Ultraviolet Telescope (MUVT) is one of the payloads on the Chang'e-3 (CE-3) lunar lander. Because of the advantages of having no at- mospheric disturbances and the slow rotation of the Moon, we can make long-term continuous observations of a series of important celestial objects in the near ultra- violet band (245-340 nm), and perform a sky survey of selected areas, which can- not be completed on Earth. We can find characteristic changes in celestial brightness with time by analyzing image data from the MUVT, and deduce the radiation mech- anism and physical properties of these celestial objects after comparing with a phys- ical model. In order to explain the scientific purposes of MUVT, this article analyzes the preprocessing of MUVT image data and makes a preliminary evaluation of data quality. The results demonstrate that the methods used for data collection and prepro- cessing are effective, and the Level 2A and 2B image data satisfy the requirements of follow-up scientific researches. 展开更多
关键词 Chang'e-3 mission -- the Moon-based Ultraviolet Telescope -- data preprocessing -- near ultraviolet band
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Diabetes Type 2: Poincaré Data Preprocessing for Quantum Machine Learning 被引量:1
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作者 Daniel Sierra-Sosa Juan D.Arcila-Moreno +1 位作者 Begonya Garcia-Zapirain Adel Elmaghraby 《Computers, Materials & Continua》 SCIE EI 2021年第5期1849-1861,共13页
Quantum Machine Learning(QML)techniques have been recently attracting massive interest.However reported applications usually employ synthetic or well-known datasets.One of these techniques based on using a hybrid appr... Quantum Machine Learning(QML)techniques have been recently attracting massive interest.However reported applications usually employ synthetic or well-known datasets.One of these techniques based on using a hybrid approach combining quantum and classic devices is the Variational Quantum Classifier(VQC),which development seems promising.Albeit being largely studied,VQC implementations for“real-world”datasets are still challenging on Noisy Intermediate Scale Quantum devices(NISQ).In this paper we propose a preprocessing pipeline based on Stokes parameters for data mapping.This pipeline enhances the prediction rates when applying VQC techniques,improving the feasibility of solving classification problems using NISQ devices.By including feature selection techniques and geometrical transformations,enhanced quantum state preparation is achieved.Also,a representation based on the Stokes parameters in the PoincaréSphere is possible for visualizing the data.Our results show that by using the proposed techniques we improve the classification score for the incidence of acute comorbid diseases in Type 2 Diabetes Mellitus patients.We used the implemented version of VQC available on IBM’s framework Qiskit,and obtained with two and three qubits an accuracy of 70%and 72%respectively. 展开更多
关键词 Quantum machine learning data preprocessing stokes parameters Poincarésphere
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An improved adaptive preprocessing method for TDI CCD images 被引量:1
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作者 郑亮亮 金光 +1 位作者 徐伟 曲宏松 《Optoelectronics Letters》 EI 2018年第1期76-80,共5页
In order to achieve high quality images with time-delayed integration(TDI) charge-coupled device(CCD) imaging system, an improved adaptive preprocessing method is proposed with functions of both denoising and edge enh... In order to achieve high quality images with time-delayed integration(TDI) charge-coupled device(CCD) imaging system, an improved adaptive preprocessing method is proposed with functions of both denoising and edge enhancement. It is a weighted average filter integrating the average filter and the improved range filter. The weighted factors are deduced in terms of a cost function, which are adjustable to different images. To validate the proposed method, extensive tests are carried out on a developed TDI CCD imaging system. The experimental results confirm that this preprocessing method can fulfill the noise removal and edge sharpening simultaneously, which can play an important role in remote sensing field. 展开更多
关键词 CCD An improved adaptive preprocessing method for TDI CCD images TDI
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AN LBP-BASED MULTI-SCALE ILLUMINATION PREPROCESSING METHOD FOR FACE RECOGNITION 被引量:1
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作者 Jiang Guoxing Cheng Yanfang 《Journal of Electronics(China)》 2009年第4期509-516,共8页
It is one of the major challenges for face recognition to minimize the disadvantage of il- lumination variations of face images in different scenarios. Local Binary Pattern (LBP) has been proved to be successful for f... It is one of the major challenges for face recognition to minimize the disadvantage of il- lumination variations of face images in different scenarios. Local Binary Pattern (LBP) has been proved to be successful for face recognition. However, it is still very rare to take LBP as an illumination preprocessing approach. In this paper, we propose a new LBP-based multi-scale illumination pre- processing method. This method mainly includes three aspects: threshold adjustment, multi-scale addition and symmetry restoration/neighborhood replacement. Our experiment results show that the proposed method performs better than the existing LBP-based methods at the point of illumination preprocessing. Moreover, compared with some face image preprocessing methods, such as histogram equalization, Gamma transformation, Retinex, and simplified LBP operator, our method can effectively improve the robustness for face recognition against illumination variation, and achieve higher recog- nition rate. 展开更多
关键词 Face recognition Illumination preprocessing Local Binary Pattern (LBP)
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Systematic review of data-centric approaches in artificial intelligence and machine learning 被引量:5
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作者 Prerna Singh 《Data Science and Management》 2023年第3期144-157,共14页
Artificial intelligence(AI)relies on data and algorithms.State-of-the-art(SOTA)AI smart algorithms have been developed to improve the performance of AI-oriented structures.However,model-centric approaches are limited ... Artificial intelligence(AI)relies on data and algorithms.State-of-the-art(SOTA)AI smart algorithms have been developed to improve the performance of AI-oriented structures.However,model-centric approaches are limited by the absence of high-quality data.Data-centric AI is an emerging approach for solving machine learning(ML)problems.It is a collection of various data manipulation techniques that allow ML practitioners to systematically improve the quality of the data used in an ML pipeline.However,data-centric AI approaches are not well documented.Researchers have conducted various experiments without a clear set of guidelines.This survey highlights six major data-centric AI aspects that researchers are already using to intentionally or unintentionally improve the quality of AI systems.These include big data quality assessment,data preprocessing,transfer learning,semi-supervised learning,machine learning operations(MLOps),and the effect of adding more data.In addition,it highlights recent data-centric techniques adopted by ML practitioners.We addressed how adding data might harm datasets and how HoloClean can be used to restore and clean them.Finally,we discuss the causes of technical debt in AI.Technical debt builds up when software design and implementation decisions run into“or outright collide with”business goals and timelines.This survey lays the groundwork for future data-centric AI discussions by summarizing various data-centric approaches. 展开更多
关键词 DATA-CENTRIC Machine learning Semi-supervised learning Data preprocessing MLOps Data management Technical debt
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A Novel Efficient and Effective Preprocessing Algorithm for Text Classification 被引量:1
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作者 Lijie Zhu Difan Luo 《Journal of Computer and Communications》 2023年第3期1-14,共14页
Text classification is an essential task of natural language processing. Preprocessing, which determines the representation of text features, is one of the key steps of text classification architecture. It proposed a ... Text classification is an essential task of natural language processing. Preprocessing, which determines the representation of text features, is one of the key steps of text classification architecture. It proposed a novel efficient and effective preprocessing algorithm with three methods for text classification combining the Orthogonal Matching Pursuit algorithm to perform the classification. The main idea of the novel preprocessing strategy is that it combined stopword removal and/or regular filtering with tokenization and lowercase conversion, which can effectively reduce the feature dimension and improve the text feature matrix quality. Simulation tests on the 20 newsgroups dataset show that compared with the existing state-of-the-art method, the new method reduces the number of features by 19.85%, 34.35%, 26.25% and 38.67%, improves accuracy by 7.36%, 8.8%, 5.71% and 7.73%, and increases the speed of text classification by 17.38%, 25.64%, 23.76% and 33.38% on the four data, respectively. 展开更多
关键词 Text Classification preprocessing Feature Dimension Orthogonal Matching Pursuit
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