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A novel speech emotion recognition algorithm based on combination of emotion data field and ant colony search strategy 被引量:3
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作者 查诚 陶华伟 +3 位作者 张昕然 周琳 赵力 杨平 《Journal of Southeast University(English Edition)》 EI CAS 2016年第2期158-163,共6页
In order to effectively conduct emotion recognition from spontaneous, non-prototypical and unsegmented speech so as to create a more natural human-machine interaction; a novel speech emotion recognition algorithm base... In order to effectively conduct emotion recognition from spontaneous, non-prototypical and unsegmented speech so as to create a more natural human-machine interaction; a novel speech emotion recognition algorithm based on the combination of the emotional data field (EDF) and the ant colony search (ACS) strategy, called the EDF-ACS algorithm, is proposed. More specifically, the inter- relationship among the turn-based acoustic feature vectors of different labels are established by using the potential function in the EDF. To perform the spontaneous speech emotion recognition, the artificial colony is used to mimic the turn- based acoustic feature vectors. Then, the canonical ACS strategy is used to investigate the movement direction of each artificial ant in the EDF, which is regarded as the emotional label of the corresponding turn-based acoustic feature vector. The proposed EDF-ACS algorithm is evaluated on the continueous audio)'visual emotion challenge (AVEC) 2012 dataset, which contains the spontaneous, non-prototypical and unsegmented speech emotion data. The experimental results show that the proposed EDF-ACS algorithm outperforms the existing state-of-the-art algorithm in turn-based speech emotion recognition. 展开更多
关键词 speech emotion recognition emotional data field ant colony search human-machine interaction
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VISUALIZATION OF THREE-DIMENSIONAL DATA FIELD AND ITS APPLICATION IN MACHINE TESTING
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作者 YIN Aijun QIN Shuren TANG Baoping 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第1期81-84,共4页
In order to realize visualization of three-dimensional data field (TDDF) in instrument, two methods of visualization of TDDF and the usual manner of quick graphic and image processing are analyzed. And how to use Op... In order to realize visualization of three-dimensional data field (TDDF) in instrument, two methods of visualization of TDDF and the usual manner of quick graphic and image processing are analyzed. And how to use OpenGL technique and the characteristic of analyzed data to construct a TDDF, the ways of reality processing and interactive processing are described. Then the medium geometric element and a related realistic model are constructed by means of the first algorithm. Models obtained for attaching the third dimension in three-dimensional data field are presented. An example for TDDF realization of machine measuring is provided. The analysis of resultant graphic indicates that the three-dimensional graphics built by the method developed is featured by good reality, fast processing and strong interaction 展开更多
关键词 Visualization in scientific computing Three-dimensional data field (TDDF) Test
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Battery pack capacity estimation for electric vehicles based on enhanced machine learning and field data
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作者 Qingguang Qi Wenxue Liu +3 位作者 Zhongwei Deng Jinwen Li Ziyou Song Xiaosong Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期605-618,共14页
Accurate capacity estimation is of great importance for the reliable state monitoring,timely maintenance,and second-life utilization of lithium-ion batteries.Despite numerous works on battery capacity estimation using... Accurate capacity estimation is of great importance for the reliable state monitoring,timely maintenance,and second-life utilization of lithium-ion batteries.Despite numerous works on battery capacity estimation using laboratory datasets,most of them are applied to battery cells and lack satisfactory fidelity when extended to real-world electric vehicle(EV)battery packs.The challenges intensify for large-sized EV battery packs,where unpredictable operating profiles and low-quality data acquisition hinder precise capacity estimation.To fill the gap,this study introduces a novel data-driven battery pack capacity estimation method grounded in field data.The proposed approach begins by determining labeled capacity through an innovative combination of the inverse ampere-hour integral,open circuit voltage-based,and resistance-based correction methods.Then,multiple health features are extracted from incremental capacity curves,voltage curves,equivalent circuit model parameters,and operating temperature to thoroughly characterize battery aging behavior.A feature selection procedure is performed to determine the optimal feature set based on the Pearson correlation coefficient.Moreover,a convolutional neural network and bidirectional gated recurrent unit,enhanced by an attention mechanism,are employed to estimate the battery pack capacity in real-world EV applications.Finally,the proposed method is validated with a field dataset from two EVs,covering approximately 35,000 kilometers.The results demonstrate that the proposed method exhibits better estimation performance with an error of less than 1.1%compared to existing methods.This work shows great potential for accurate large-sized EV battery pack capacity estimation based on field data,which provides significant insights into reliable labeled capacity calculation,effective features extraction,and machine learning-enabled health diagnosis. 展开更多
关键词 Electricvehicle Lithium-ion battery pack Capacity estimation Machine learning field data
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Structural Setting of the South-West Cameroon Using Satellite Potential Field Derived from SGG-UGM-2 Gravity Data
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作者 Jean Aimé Mono 《Journal of Geoscience and Environment Protection》 2024年第8期43-61,共19页
This study aims to improve knowledge of the structure of southwest Cameroon based on the analysis and interpretation of gravity data derived from the SGG-UGM-2 model. A residual anomaly map was first calculated from t... This study aims to improve knowledge of the structure of southwest Cameroon based on the analysis and interpretation of gravity data derived from the SGG-UGM-2 model. A residual anomaly map was first calculated from the Bouguer anomaly map, which is strongly affected by a regional gradient. The residual anomaly map generated provides information on the variation in subsurface density, but does not provide sufficient information, hence the interest in using filtering with the aim of highlighting the structures affecting the area of south-west Cameroon. Three interpretation methods were used: vertical gradient, horizontal gradient coupled with upward continuation and Euler deconvolution. The application of these treatments enabled us to map a large number of gravimetric lineaments materializing density discontinuities. These lineaments are organized along main preferential directions: NW-SE, NNE-SSW, ENE-WSW and secondary directions: NNW-SSE, NE-SW, NS and E-W. Euler solutions indicate depths of up to 7337 m. Thanks to the results of this research, significant information has been acquired, contributing to a deeper understanding of the structural composition of the study area. The resulting structural map vividly illustrates the major tectonic events that shaped the geological framework of the study area. It also serves as a guide for prospecting subsurface resources (water and hydrocarbons). . 展开更多
关键词 SGG-UGM-2 Model Horizontal Gradient Bouguer Anomalies Potential field data
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Full-Scale Numerical Simulation of the Local Scour Under Combined Current and Wave Conditions Based on Field Data 被引量:1
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作者 SUI Shu-huan ZHAO Xue-liang +2 位作者 CHEN Xin-rui DENG Wen-ni SHEN Kan-min 《China Ocean Engineering》 SCIE EI CSCD 2023年第6期1032-1043,共12页
The monopile is the most common foundation to support offshore wind turbines.In the marine environment,local scour due to combined currents and waves is a significant issue that must be considered in the design of win... The monopile is the most common foundation to support offshore wind turbines.In the marine environment,local scour due to combined currents and waves is a significant issue that must be considered in the design of wind turbine foundations.In this paper,a full-scale numerical model was developed and validated based on field data from Rudong,China.The scour development around monopiles was investigated,and the effects of waves and the Reynolds number Re were analyzed.Several formulas for predicting the scour depth in the literature have been evaluated.It is found that waves can accelerate scour development even if the KC number is small(0.78<KC<1.57).The formula obtained from small-scale model tests may be unsafe or wasteful when it is applied in practical design due to the scale effect.A new equation for predicting the scour depth based on the average pile Reynolds number(Rea)is proposed and validated with field data.The equilibrium scour depth predicted using the proposed equation is evaluated and compared with those from nine equations in the literature.It is demonstrated that the values predicted from the proposed equation and from the S/M(Sheppard/Melville)equation are closer to the field data. 展开更多
关键词 full-scale numerical simulation field data scale effect Reynolds number effects local scour
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Application of Image Enhancement Techniques to Potential Field Data 被引量:6
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作者 张丽莉 郝天珧 +1 位作者 吴健生 王家林 《Applied Geophysics》 SCIE CSCD 2005年第3期145-152,i0001,共9页
In this paper the application of image enhancement techniques to potential field data is briefly described and two improved enhancement methods are introduced. One method is derived from the histogram equalization tec... In this paper the application of image enhancement techniques to potential field data is briefly described and two improved enhancement methods are introduced. One method is derived from the histogram equalization technique and automatically determines the color spectra of geophysical maps. Colors can be properly distributed and visual effects and resolution can be enhanced by the method. The other method is based on the modified Radon transform and gradient calculation and is used to detect and enhance linear features in gravity and magnetic images. The method facilites the detection of line segments in the transform domain. Tests with synthetic images and real data show the methods to be effective in feature enhancement. 展开更多
关键词 image enhancement histogram equalization Radon transform and potential field data
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Spectral-spatial target detection based on data field modeling for hyperspectral data 被引量:4
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作者 Da LIU Jianxun LI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第4期795-805,共11页
Target detection is always an important application in hyperspectral image processing field. In this paper, a spectral-spatial target detection algorithm for hyperspectral data is proposed.The spatial feature and spec... Target detection is always an important application in hyperspectral image processing field. In this paper, a spectral-spatial target detection algorithm for hyperspectral data is proposed.The spatial feature and spectral feature were unified based on the data filed theory and extracted by weighted manifold embedding. The novelties of the proposed method lie in two aspects. One is the way in which the spatial features and spectral features were fused as a new feature based on the data field theory, and the other is that local information was introduced to describe the decision boundary and explore the discriminative features for target detection. The extracted features based on data field modeling and manifold embedding techniques were considered for a target detection task.Three standard hyperspectral datasets were considered in the analysis. The effectiveness of the proposed target detection algorithm based on data field theory was proved by the higher detection rates with lower False Alarm Rates(FARs) with respect to those achieved by conventional hyperspectral target detectors. 展开更多
关键词 data field modeling Feature extraction Hyperspectral data Spectral-spatial Target detection
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Behavior Mining of Spatial Objects with Data Field 被引量:2
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作者 王树良 伍爵博 +2 位作者 程峰 金红 曾寔 《Geo-Spatial Information Science》 2009年第3期202-211,共10页
The advanced data mining technologies and the large quantities of remotely sensed Imagery provide a data mining opportunity with high potential for useful results. Extracting interesting patterns and rules from data s... The advanced data mining technologies and the large quantities of remotely sensed Imagery provide a data mining opportunity with high potential for useful results. Extracting interesting patterns and rules from data sets composed of images and associated ground data can be of importance in object identification, community planning, resource discovery and other areas. In this paper, a data field is presented to express the observed spatial objects and conduct behavior mining on them. First, most of the important aspects are discussed on behavior mining and its implications for the future of data mining. Furthermore, an ideal framework of the behavior mining system is proposed in the network environment. Second, the model of behavior mining is given on the observed spatial objects, including the objects described by the first feature data field and the main feature data field by means of the potential function. Finally, a case study about object identification in public is given and analyzed. The experimental results show that the new model is feasible in behavior mining. 展开更多
关键词 behavior mining data field spatial object identification spatial data mining
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A new edge recognition technology based on the normalized vertical derivative of the total horizontal derivative for potential field data 被引量:94
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作者 Wang Wanyin Pan Yu Qiu Zhiyun 《Applied Geophysics》 SCIE CSCD 2009年第3期226-233,299,共9页
Edge detection and enhancement techniques are commonly used in recognizing the edge of geologic bodies using potential field data. We present a new edge recognition technology based on the normalized vertical derivati... Edge detection and enhancement techniques are commonly used in recognizing the edge of geologic bodies using potential field data. We present a new edge recognition technology based on the normalized vertical derivative of the total horizontal derivative which has the functions of both edge detection and enhancement techniques. First, we calculate the total horizontal derivative (THDR) of the potential-field data and then compute the n-order vertical derivative (VDRn) of the THDR. For the n-order vertical derivative, the peak value of total horizontal derivative (PTHDR) is obtained using a threshold value greater than 0. This PTHDR can be used for edge detection. Second, the PTHDR value is divided by the total horizontal derivative and normalized by the maximum value. Finally, we used different kinds of numerical models to verify the effectiveness and reliability of the new edge recognition technology. 展开更多
关键词 potential field data edge recognition edge enhancement total horizontal derivative normalized vertical derivative
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On the Efficiency of a CFD-Based Full Convolution Neural Network for the Post-Processing of Field Data 被引量:3
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作者 Sheng Bai Feng Bao Fengzhi Zhao 《Fluid Dynamics & Materials Processing》 EI 2021年第1期39-47,共9页
The present study aims to improve the efficiency of typical procedures used for post-processing flow field data by applying a neural-network technology.Assuming a problem of aircraft design as the workhorse,a regressi... The present study aims to improve the efficiency of typical procedures used for post-processing flow field data by applying a neural-network technology.Assuming a problem of aircraft design as the workhorse,a regression calculation model for processing the flow data of a FCN-VGG19 aircraft is elaborated based on VGGNet(Visual Geometry Group Net)and FCN(Fully Convolutional Network)techniques.As shown by the results,the model displays a strong fitting ability,and there is almost no over-fitting in training.Moreover,the model has good accuracy and convergence.For different input data and different grids,the model basically achieves convergence,showing good performances.It is shown that the proposed simulation regression model based on FCN has great potential in typical problems of computational fluid dynamics(CFD)and related data processing. 展开更多
关键词 CFD aircraft design FCN processing of flow field data regression calculation model
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Research of Methods for Lost Data Reconstruction in Erasure Codes over Binary Fields 被引量:2
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作者 Dan Tang 《Journal of Electronic Science and Technology》 CAS CSCD 2016年第1期43-48,共6页
In the process of encoding and decoding,erasure codes over binary fields,which just need AND operations and XOR operations and therefore have a high computational efficiency,are widely used in various fields of inform... In the process of encoding and decoding,erasure codes over binary fields,which just need AND operations and XOR operations and therefore have a high computational efficiency,are widely used in various fields of information technology.A matrix decoding method is proposed in this paper.The method is a universal data reconstruction scheme for erasure codes over binary fields.Besides a pre-judgment that whether errors can be recovered,the method can rebuild sectors of loss data on a fault-tolerant storage system constructed by erasure codes for disk errors.Data reconstruction process of the new method has simple and clear steps,so it is beneficial for implementation of computer codes.And more,it can be applied to other non-binary fields easily,so it is expected that the method has an extensive application in the future. 展开更多
关键词 Binary fields data reconstruction decoding erasure codes
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Ensembling Neural Networks for User’s Indoor Localization Using Magnetic Field Data from Smartphones 被引量:1
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作者 Imran Ashraf Soojung Hur +1 位作者 Yousaf Bin Zikria Yongwan Park 《Computers, Materials & Continua》 SCIE EI 2021年第8期2597-2620,共24页
Predominantly the localization accuracy of the magnetic field-based localization approaches is severed by two limiting factors:Smartphone heterogeneity and smaller data lengths.The use of multifarioussmartphones cripp... Predominantly the localization accuracy of the magnetic field-based localization approaches is severed by two limiting factors:Smartphone heterogeneity and smaller data lengths.The use of multifarioussmartphones cripples the performance of such approaches owing to the variability of the magnetic field data.In the same vein,smaller lengths of magnetic field data decrease the localization accuracy substantially.The current study proposes the use of multiple neural networks like deep neural network(DNN),long short term memory network(LSTM),and gated recurrent unit network(GRN)to perform indoor localization based on the embedded magnetic sensor of the smartphone.A voting scheme is introduced that takes predictions from neural networks into consideration to estimate the current location of the user.Contrary to conventional magnetic field-based localization approaches that rely on the magnetic field data intensity,this study utilizes the normalized magnetic field data for this purpose.Training of neural networks is carried out using Galaxy S8 data while the testing is performed with three devices,i.e.,LG G7,Galaxy S8,and LG Q6.Experiments are performed during different times of the day to analyze the impact of time variability.Results indicate that the proposed approach minimizes the impact of smartphone variability and elevates the localization accuracy.Performance comparison with three approaches reveals that the proposed approach outperforms them in mean,50%,and 75%error even using a lesser amount of magnetic field data than those of other approaches. 展开更多
关键词 Indoor localization magnetic field data long short term memory network data normalization gated recurrent unit network deep learning
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Nonlinear Inversion of Potential-Field Data Using an Improved Genetic Algorithm 被引量:1
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作者 FengGangding ChenChao 《Journal of China University of Geosciences》 SCIE CSCD 2004年第4期420-424,共5页
The genetic algorithm is useful for solving an inversion of complex nonlinear geophysical equations. The multi-point search of the genetic algorithm makes it easier to find a globally optimal solution and avoid fall... The genetic algorithm is useful for solving an inversion of complex nonlinear geophysical equations. The multi-point search of the genetic algorithm makes it easier to find a globally optimal solution and avoid falling into a local extremum. The search efficiency of the genetic algorithm is a key to producing successful solutions in a huge multi-parameter model space. The encoding mechanism of the genetic algorithm affects the searching processes in the evolution. Not all genetic operations perform perfectly in a search under either a binary or decimal encoding system. As such, a standard genetic algorithm (SGA) is sometimes unable to resolve an optimization problem such as a simple geophysical inversion. With the binary encoding system the operation of the crossover may produce more new individuals. The decimal encoding system, on the other hand, makes the mutation generate more new genes. This paper discusses approaches of exploiting the search potentials of genetic operations with different encoding systems and presents a hybrid-encoding mechanism for the genetic algorithm. This is referred to as the hybrid-encoding genetic algorithm (HEGA). The method is based on the routine in which the mutation operation is executed in decimal code and other operations in binary code. HEGA guarantees the birth of better genes by mutation processing with a high probability, so that it is beneficial for resolving the inversions of complicated problems. Synthetic and real-world examples demonstrate the advantages of using HEGA in the inversion of potential-field data. 展开更多
关键词 INVERSION genetic algorithm potential-field data.
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Information Science Roles in the Emerging Field of Data Science 被引量:1
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作者 Gary Marchionini 《Journal of Data and Information Science》 2016年第2期1-6,共6页
There has long been discussion about the distinctions of library science,information science,and informatics,and how these areas differ and overlap with computer science.Today the term data science is emerging that ge... There has long been discussion about the distinctions of library science,information science,and informatics,and how these areas differ and overlap with computer science.Today the term data science is emerging that generates excitement and questions about how it relates to and differs from these other areas of study. 展开更多
关键词 Information Science Roles in the Emerging field of data Science
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Pure q P-wave least-squares reverse time migration invertically transverse isotropic media and its application to field data
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作者 Huang Jian-Ping Mu Xin-Ru +3 位作者 Li Zhen-Chun Li Qing-Yang Yuan Shuang-Qi Guo Yun-Dong 《Applied Geophysics》 SCIE CSCD 2020年第2期208-220,315,共14页
The anisotropic properties of subsurface media cause waveform distortions in seismic wave propagation,resulting in a negative infl uence on seismic imaging.In addition,wavefields simulated by the conventional coupled ... The anisotropic properties of subsurface media cause waveform distortions in seismic wave propagation,resulting in a negative infl uence on seismic imaging.In addition,wavefields simulated by the conventional coupled pseudo-acoustic equation are not only aff ected by SV-wave artifacts but are also limited by anisotropic parameters.We propose a least-squares reverse time migration(LSRTM)method based on the pure q P-wave equation in vertically transverse isotropic media.A fi nite diff erence and fast Fourier transform method,which can improve the effi ciency of the numerical simulation compared to a pseudo-spectral method,is used to solve the pure q P-wave equation.We derive the corresponding demigration operator,migration operator,and gradient updating formula to implement the LSRTM.Numerical tests on the Hess model and field data confirm that the proposed method has a good correction eff ect for the travel time deviation caused by underground anisotropic media.Further,it signifi cantly suppresses the migration noise,balances the imaging amplitude,and improves the imaging resolution. 展开更多
关键词 Pure qP-wave equation vertically transverse isotropic media LSRTM finite difference and fast Fourier transform field data
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Web-based GIS System for Real-time Field Data Collection Using Personal Mobile Phone 被引量:2
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作者 Ko Ko Lwin Yuji Murayama 《Journal of Geographic Information System》 2011年第4期382-389,共8页
Recently, use of mobile communicational devices in field data collection is increasing such as smart phones and cellular phones due to emergence of embedded Global Position System GPS and Wi-Fi Internet access. Accura... Recently, use of mobile communicational devices in field data collection is increasing such as smart phones and cellular phones due to emergence of embedded Global Position System GPS and Wi-Fi Internet access. Accurate timely and handy field data collection is required for disaster management and emergency quick responses. In this article, we introduce web-based GIS system to collect the field data by personal mobile phone through Post Office Protocol POP3 mail server. The main objective of this work is to demonstrate real-time field data collection method to the students using their mobile phone to collect field data by timely and handy manners, either individual or group survey in local or global scale research. 展开更多
关键词 WEB-BASED GIS System REAL-TIME field data Collection PERSONAL Mobile PHONE POP3 MAIL Server
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Crop Calendar Mapping of Bangladesh Rice Paddy Field with ALOS-2 ScanSAR Data
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作者 Md. Rahedul Islam 《Advances in Remote Sensing》 2021年第3期115-129,共15页
Rice paddy mapping with optical remote sensing is challenging in Bangladesh due to the heterogeneous cropping pattern, fragmented field size and cloud </span><span style="font-family:Verdana;">co... Rice paddy mapping with optical remote sensing is challenging in Bangladesh due to the heterogeneous cropping pattern, fragmented field size and cloud </span><span style="font-family:Verdana;">cover during the growing period. The high-resolution Synthetic Aperture</span><span style="font-family:Verdana;"> Radar (SAR) sensor is the potential alternate to mapping rice area in Bangla</span><span style="font-family:Verdana;">desh. The L-band SAR sensor onboard Advanced Land Observing Satellit</span><span style="font-family:Verdana;">e (</span><span style="font-family:Verdana;">ALOS) acquires multi-polarization and multi-temporal images are </span><span style="font-family:Verdana;">a very useful tool for rice area mapping. In this study, we used ALOS-2 ScanSAR dual (HH</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">+</span><span style="font-family:""> </span><span style="font-family:Verdana;">HV) polarized time series data in the study area. We used orthorectification and slope corrected backscatter (sigma-naught) images and median filtering (3 × 3) window for image processing. The unsupervised classification with the k-means++ algorithm is used for initial clustering (20 categories) of images over the study area. The GPS location of rice paddy field with cropping pattern over study area uses for classifying the different rice-growing season from the k-means clustering data. The result is compared with the moderate resolution imaging spectroradiometer (MODIS) based rice area and national statistical agricultural yearbook statistics. The results show that, based on the MODIS based rice map, the rice fields can be mapped with a conditional Kappa value of 0.68 and at user’s and producer’s accuracies of 86% and 90%, respectively. The large commission error primarily came from confusion between wet season Aus rice and others crop, Aus-Amon and Boro-Aus-Amon cropping pattern because of their similar backscatter amplitudes and temporal similarities in the rice growing season. The relatively high rice mapping accuracy in this study indicates that the ALOS/PALSAR-2 data could provide useful information in rice cropping management in subtropical regions such Bangladesh. 展开更多
关键词 K-Means++ Unsupervised Classification Moderate Resolution Imaging Spectroradiometer (MODIS) Backscatter Co-Efficient field data
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The Regional Surface Heating Field over the Heterogeneous Landscape of the Tibetan Plateau Using MODIS and In Situ Data 被引量:5
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作者 MA Yaoming WANG Binbin +1 位作者 ZHONG Lei MA Weiqiang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第1期47-53,共7页
In this study, a parameterization scheme based on Moderate Resolution Imaging Spectroradiometer (MODIS) data and in-situ data was tested for deriving the regional surface heating field over a heterogeneous landscape... In this study, a parameterization scheme based on Moderate Resolution Imaging Spectroradiometer (MODIS) data and in-situ data was tested for deriving the regional surface heating field over a heterogeneous landscape. As a case study, the methodology was applied to the whole Tibetan Plateau (TP) area. Four images of MODIS data (i.e., 30 January 2007, 15 April 2007, 1 August 2007, and 25 October 2007) were used in this study for comparison among winter, spring, summer, and autumn. The results were validated using the observations measured at the stations of the Tibetan Observation and Research Platform (TORP). The results show the following: (1) The derived surface heating field for the TP area was in good accord with the land-surface status, showing a wide range of values due to the strong contrast of surface features in the area. (2) The derived surface heating field for the TP was very close to the field measurements (observations). The APD (absolute percent difference) between the derived results and the field observations was 〈10%. (3) The mean surface heating field over the TP increased from January to April to August, and decreased in October. Therefore, the reasonable regional distribution of the surface heating field over a heterogeneous landscape can be obtained using this methodology. The limitations and further improvement of this method are also discussed. 展开更多
关键词 regional surface heating field Tibetan Plateau MODIS in-situ data
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UNIQUENESS OF INVERSE TRANSMISSION SCATTERING WITH A CONDUCTIVE BOUNDARY CONDITION BY PHASELESS FAR FIELD PATTERN
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作者 向建立 严国政 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期450-468,共19页
In this paper,we establish the unique determination result for inverse acoustic scattering of a penetrable obstacle with a general conductive boundary condition by using phaseless far field data at a fixed frequency.I... In this paper,we establish the unique determination result for inverse acoustic scattering of a penetrable obstacle with a general conductive boundary condition by using phaseless far field data at a fixed frequency.It is well-known that the modulus of the far field pattern is invariant under translations of the scattering obstacle if only one plane wave is used as the incident field,so it is impossible to reconstruct the location of the underlying scatterers.Based on some new research results on the impenetrable obstacle and inhomogeneous isotropic medium,we consider different types of superpositions of incident waves to break the translation invariance property. 展开更多
关键词 conductive boundary condition UNIQUENESS phaseless far field data inverse scattering
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Data field for mining big data 被引量:1
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作者 Shuliang Wang Ying Li Dakui Wang 《Geo-Spatial Information Science》 CSCD 2016年第2期中插2-中插2,106-118,共14页
Big data is a highlighted challenge for many fields with the rapid expansion of large-volume, complex, and fast-growing sources of data. Mining from big data is required for exploring the essence of data and providing... Big data is a highlighted challenge for many fields with the rapid expansion of large-volume, complex, and fast-growing sources of data. Mining from big data is required for exploring the essence of data and providing meaningful information. To this end, we have previously introduced the theory of physical field to explore relations between objects in data space and proposed a framework of data field to discover the underlying distribution of big data. This paper concerns an overview of big data mining by the use of data field. It mainly discusses the theory of data field and different aspects of applications including feature selection for high-dimensional data, clustering, and the recognition of facial expression in human-computer interaction. In these applications, data field is employed to capture the intrinsic distribution of data objects for selecting meaningful features, fast clustering, and describing variation of facial expression. It is expected that our contributions would help overcome the problems in accordance with big data. 展开更多
关键词 Physical field data field BIG data MINING FEATURE selection hierarchical clustering recognition of FACE expression
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