The problem of combined radar imagery from multiple sparse frequency subbands initially incoherent to each other is of practical importance for radar target discrimination.A new coherent processing technique based on ...The problem of combined radar imagery from multiple sparse frequency subbands initially incoherent to each other is of practical importance for radar target discrimination.A new coherent processing technique based on probability density analysis of the subband data is proposed,which is applicable for radar imaging from measurements of two or more initially incoherent radar subbands.The coherence parameters for both amplitude and phase are obtained by combining modern spectral analysis with probability density estimation.The major advantage of the proposed technique lies in that it enables much more robust cohering for the sparse subband data of real-world complex targets.展开更多
A method to detect airports in large space-borne synthetic aperture radar(SAR) imagery is studied.First,the large SAR imagery is segmented according to amplitude characteristics using maximum a posteriori(MAP) est...A method to detect airports in large space-borne synthetic aperture radar(SAR) imagery is studied.First,the large SAR imagery is segmented according to amplitude characteristics using maximum a posteriori(MAP) estimator based on the heavytailed Rayleigh model.The attention is then paid on the object of interest(OOI) extracted from the large images.The minimumarea enclosing rectangle(MER) of OOI is created via a rotating calipers algorithm.The projection histogram(PH) of MER for OOI is then computed and the scale and rotation invariant feature for OOI are extracted from the statistical characteristics of PH.A support vector machine(SVM) classifier is trained using those feature parameters and the airport is detected by the SVM classifier and Hough transform.The application in space-borne SAR images demonstrates the effectiveness of the proposed method.展开更多
Phrasal verbs,such as look after,look forward to,look through,etc.,account for a large per-centage in English vocabulary,and they are even more difficult than single words for.English learn-ers to learn.For one reason...Phrasal verbs,such as look after,look forward to,look through,etc.,account for a large per-centage in English vocabulary,and they are even more difficult than single words for.English learn-ers to learn.For one reason,they are of a large quantity by formation.By looking throughWebster’s Third New International Dictionary(1961),we can see how colorful the forms of展开更多
"Nineteen",a poem by Elizabeth Alexander,is more than a story of a gir's "first summer away from home." Through the use of carefully chosen imagery and diction,the development of characters,the..."Nineteen",a poem by Elizabeth Alexander,is more than a story of a gir's "first summer away from home." Through the use of carefully chosen imagery and diction,the development of characters,the use of details,the variation in meters and the use of enjambment,the poet has parallels both the story of the speaker and that of her lover.More importantly,the lesson the speaker learns through her experience is especially rewarding.展开更多
Compared with Spenser's Sonnet 15 in which the speaker praises his beautiful lover by comparing her to various precious things such as Saphyres,Rubies,pearles,yvory,gold and silver,the speaker in Shakespeare's...Compared with Spenser's Sonnet 15 in which the speaker praises his beautiful lover by comparing her to various precious things such as Saphyres,Rubies,pearles,yvory,gold and silver,the speaker in Shakespeare's Sonnet 130 denies that his lover is as perfect as such wonderful things as the sun,coral,snow,roses,perfume,music and goddess,and thus portrays a more human and believable beauty.In addition,he describes his lovers in four senses-the visual sense,the sense of smell,the sense of sound,and the sense of motion.As a result,he creates a vivid and genuine beauty.展开更多
Shakespeare's sonnet 73 impresses the readers with its rich images,metaphors,and profound diction.A study of the form that the poem has taken,of its imagery and its diction,we can conclude that the poem is not mer...Shakespeare's sonnet 73 impresses the readers with its rich images,metaphors,and profound diction.A study of the form that the poem has taken,of its imagery and its diction,we can conclude that the poem is not merely a cry of personal fear for and anxiety about aging and dying.Instead,it reflects the poet's sentimental attachment to life and resistance to death.展开更多
For anomaly detection,anomalies existing in the background will affect the detection performance.Accordingly,a background refinement method based on the local density is proposed to remove the anomalies from thebackgr...For anomaly detection,anomalies existing in the background will affect the detection performance.Accordingly,a background refinement method based on the local density is proposed to remove the anomalies from thebackground.In this work,the local density is measured by its spectral neighbors through a certain radius which is obtained by calculating the mean median of the distance matrix.Further,a two-step segmentation strategy is designed.The first segmentation step divides the original background into two subsets,a large subset composed by background pixels and a small subset containing both background pixels and anomalies.The second segmentation step employing Otsu method with an aim to obtain a discrimination threshold is conducted on the small subset.Then the pixels whose local densities are lower than the threshold are removed.Finally,to validate the effectiveness of the proposed method,it combines Reed-Xiaoli detector and collaborative-representation-based detector to detect anomalies.Experiments are conducted on two real hyperspectral datasets.Results show that the proposed method achieves better detection performance.展开更多
Multifrequency polarimetric SAR imagery provides a very convenient approach for signal processing and acquisition of radar image. However, the amount of information is scattered in several images, and redundancies exi...Multifrequency polarimetric SAR imagery provides a very convenient approach for signal processing and acquisition of radar image. However, the amount of information is scattered in several images, and redundancies exist between different bands and polarizations. Similar to signal-polarimetric SAR image, multifrequency polarimetric SAR image is corrupted with speckle noise at the same time. A method of information compression and speckle reduction for multifrequency polarimetric SAR imagery is presented based on kernel principal component analysis (KPCA). KPCA is a nonlinear generalization of the linear principal component analysis using the kernel trick. The NASA/JPL polarimetric SAR imagery of P, L, and C bands quadpolarizations is used for illustration. The experimental results show that KPCA has better capability in information compression and speckle reduction as compared with linear PCA.展开更多
As a promising technique to enhance the spatial reso- lution of remote sensing imagery, sub-pixel mapping is processed based on the spatial dependence theory with the assumption that the land cover is spatially depend...As a promising technique to enhance the spatial reso- lution of remote sensing imagery, sub-pixel mapping is processed based on the spatial dependence theory with the assumption that the land cover is spatially dependent both within pixels and be- tween them. The spatial attraction is used as a tool to describe the dependence. First, the spatial attractions between pixels, sub- pixel/pixel spatial attraction model (SPSAM), are described by the modified SPSAM (MSPSAM) that estimates the attractions accord- ing to the distribution of sub-pixels within neighboring pixels. Then a mixed spatial attraction model (MSAM) for sub-pixel mapping is proposed that integrates the spatial attractions both within pix- els and between them. According to the expression of the MSAM maximumising the spatial attraction, the genetic algorithm is em- ployed to search the optimum solution and generate the sub-pixel mapping results. Experiments show that compared with SPSAM, MSPSAM and pixel swapping algorithm modified by initialization from SPSAM (MPS), MSAM can provide higher accuracy and more rational sub-pixel mapping results.展开更多
Segmentation is the key step in auto-interpretation of high-resolution spaceborne synthetic aperture radar(SAR) images. A novel method is proposed based on integrating the geometric active contour(GAC) and the sup...Segmentation is the key step in auto-interpretation of high-resolution spaceborne synthetic aperture radar(SAR) images. A novel method is proposed based on integrating the geometric active contour(GAC) and the support vector machine(SVM)models. First, the images are segmented by using SVM and textural statistics. A likelihood measurement for every pixel is derived by using the initial segmentation. The Chan-Vese model then is modified by adding two items: the likelihood and the distance between the initial segmentation and the evolving contour. Experimental results using real SAR images demonstrate the good performance of the proposed method compared to several classic GAC models.展开更多
In the history of Chinese literature,Tz's of Song Dynasty abounds in lyrics infused with sentimental gracefulness,whose most distinctive feature is the employment of rich and varied imagery.This paper is to analyz...In the history of Chinese literature,Tz's of Song Dynasty abounds in lyrics infused with sentimental gracefulness,whose most distinctive feature is the employment of rich and varied imagery.This paper is to analyze the imagery of three Tz'u lyrics of profound lamentation so as to show how the extraordinary manipulation of imagery makes the three lyrics the master pieces of their kind.展开更多
Scholarly research regarding Ruan Ji 阮籍 has predom inantly revolved either around his five-word Yonghuai Poetry( Poems from my Heart,詠懷詩). From the perspective of Escape and Escapism,the paper we call the imagery...Scholarly research regarding Ruan Ji 阮籍 has predom inantly revolved either around his five-word Yonghuai Poetry( Poems from my Heart,詠懷詩). From the perspective of Escape and Escapism,the paper we call the imagery in Ruan Ji's poetry,including his Fu-Poetry,four-word Poems as well as five-word poems,is escapist imagery. Ruan Ji has a kind of escapism complex which the paper talks over by case studies,i. e."Dongping fu"东平赋,four-word Poem IX and Poem XIII,and five-word Poem I and Poem LX X IX to find a new perspective to read Ruan Ji. This escapism complex is closely connected to Ruan Ji's unique mode of existence.展开更多
文摘The problem of combined radar imagery from multiple sparse frequency subbands initially incoherent to each other is of practical importance for radar target discrimination.A new coherent processing technique based on probability density analysis of the subband data is proposed,which is applicable for radar imaging from measurements of two or more initially incoherent radar subbands.The coherence parameters for both amplitude and phase are obtained by combining modern spectral analysis with probability density estimation.The major advantage of the proposed technique lies in that it enables much more robust cohering for the sparse subband data of real-world complex targets.
文摘A method to detect airports in large space-borne synthetic aperture radar(SAR) imagery is studied.First,the large SAR imagery is segmented according to amplitude characteristics using maximum a posteriori(MAP) estimator based on the heavytailed Rayleigh model.The attention is then paid on the object of interest(OOI) extracted from the large images.The minimumarea enclosing rectangle(MER) of OOI is created via a rotating calipers algorithm.The projection histogram(PH) of MER for OOI is then computed and the scale and rotation invariant feature for OOI are extracted from the statistical characteristics of PH.A support vector machine(SVM) classifier is trained using those feature parameters and the airport is detected by the SVM classifier and Hough transform.The application in space-borne SAR images demonstrates the effectiveness of the proposed method.
文摘Phrasal verbs,such as look after,look forward to,look through,etc.,account for a large per-centage in English vocabulary,and they are even more difficult than single words for.English learn-ers to learn.For one reason,they are of a large quantity by formation.By looking throughWebster’s Third New International Dictionary(1961),we can see how colorful the forms of
文摘"Nineteen",a poem by Elizabeth Alexander,is more than a story of a gir's "first summer away from home." Through the use of carefully chosen imagery and diction,the development of characters,the use of details,the variation in meters and the use of enjambment,the poet has parallels both the story of the speaker and that of her lover.More importantly,the lesson the speaker learns through her experience is especially rewarding.
文摘Compared with Spenser's Sonnet 15 in which the speaker praises his beautiful lover by comparing her to various precious things such as Saphyres,Rubies,pearles,yvory,gold and silver,the speaker in Shakespeare's Sonnet 130 denies that his lover is as perfect as such wonderful things as the sun,coral,snow,roses,perfume,music and goddess,and thus portrays a more human and believable beauty.In addition,he describes his lovers in four senses-the visual sense,the sense of smell,the sense of sound,and the sense of motion.As a result,he creates a vivid and genuine beauty.
文摘Shakespeare's sonnet 73 impresses the readers with its rich images,metaphors,and profound diction.A study of the form that the poem has taken,of its imagery and its diction,we can conclude that the poem is not merely a cry of personal fear for and anxiety about aging and dying.Instead,it reflects the poet's sentimental attachment to life and resistance to death.
基金Projects(61405041,61571145)supported by the National Natural Science Foundation of ChinaProject(ZD201216)supported by the Key Program of Heilongjiang Natural Science Foundation,China+1 种基金Project(RC2013XK009003)supported by Program Excellent Academic Leaders of Harbin,ChinaProject(HEUCF1508)supported by the Fundamental Research Funds for the Central Universities,China
文摘For anomaly detection,anomalies existing in the background will affect the detection performance.Accordingly,a background refinement method based on the local density is proposed to remove the anomalies from thebackground.In this work,the local density is measured by its spectral neighbors through a certain radius which is obtained by calculating the mean median of the distance matrix.Further,a two-step segmentation strategy is designed.The first segmentation step divides the original background into two subsets,a large subset composed by background pixels and a small subset containing both background pixels and anomalies.The second segmentation step employing Otsu method with an aim to obtain a discrimination threshold is conducted on the small subset.Then the pixels whose local densities are lower than the threshold are removed.Finally,to validate the effectiveness of the proposed method,it combines Reed-Xiaoli detector and collaborative-representation-based detector to detect anomalies.Experiments are conducted on two real hyperspectral datasets.Results show that the proposed method achieves better detection performance.
基金the Specialized Research Found for the Doctoral Program of Higher Education (20070699013)the Natural Science Foundation of Shaanxi Province (2006F05)the Aeronautical Science Foundation (05I53076).
文摘Multifrequency polarimetric SAR imagery provides a very convenient approach for signal processing and acquisition of radar image. However, the amount of information is scattered in several images, and redundancies exist between different bands and polarizations. Similar to signal-polarimetric SAR image, multifrequency polarimetric SAR image is corrupted with speckle noise at the same time. A method of information compression and speckle reduction for multifrequency polarimetric SAR imagery is presented based on kernel principal component analysis (KPCA). KPCA is a nonlinear generalization of the linear principal component analysis using the kernel trick. The NASA/JPL polarimetric SAR imagery of P, L, and C bands quadpolarizations is used for illustration. The experimental results show that KPCA has better capability in information compression and speckle reduction as compared with linear PCA.
基金supported by the National Natural Science Foundation of China (60802059)the Foundation for the Doctoral Program of Higher Education of China (200802171003)
文摘As a promising technique to enhance the spatial reso- lution of remote sensing imagery, sub-pixel mapping is processed based on the spatial dependence theory with the assumption that the land cover is spatially dependent both within pixels and be- tween them. The spatial attraction is used as a tool to describe the dependence. First, the spatial attractions between pixels, sub- pixel/pixel spatial attraction model (SPSAM), are described by the modified SPSAM (MSPSAM) that estimates the attractions accord- ing to the distribution of sub-pixels within neighboring pixels. Then a mixed spatial attraction model (MSAM) for sub-pixel mapping is proposed that integrates the spatial attractions both within pix- els and between them. According to the expression of the MSAM maximumising the spatial attraction, the genetic algorithm is em- ployed to search the optimum solution and generate the sub-pixel mapping results. Experiments show that compared with SPSAM, MSPSAM and pixel swapping algorithm modified by initialization from SPSAM (MPS), MSAM can provide higher accuracy and more rational sub-pixel mapping results.
基金supported by the National Natural Science Foundation of China(4117132741301361)+2 种基金the National Key Basic Research Program of China(973 Program)(2012CB719903)the Science and Technology Project of Ministry of Transport of People’s Republic of China(2012-364-X11-803)the Shanghai Municipal Natural Science Foundation(12ZR1433200)
文摘Segmentation is the key step in auto-interpretation of high-resolution spaceborne synthetic aperture radar(SAR) images. A novel method is proposed based on integrating the geometric active contour(GAC) and the support vector machine(SVM)models. First, the images are segmented by using SVM and textural statistics. A likelihood measurement for every pixel is derived by using the initial segmentation. The Chan-Vese model then is modified by adding two items: the likelihood and the distance between the initial segmentation and the evolving contour. Experimental results using real SAR images demonstrate the good performance of the proposed method compared to several classic GAC models.
文摘In the history of Chinese literature,Tz's of Song Dynasty abounds in lyrics infused with sentimental gracefulness,whose most distinctive feature is the employment of rich and varied imagery.This paper is to analyze the imagery of three Tz'u lyrics of profound lamentation so as to show how the extraordinary manipulation of imagery makes the three lyrics the master pieces of their kind.
文摘Scholarly research regarding Ruan Ji 阮籍 has predom inantly revolved either around his five-word Yonghuai Poetry( Poems from my Heart,詠懷詩). From the perspective of Escape and Escapism,the paper we call the imagery in Ruan Ji's poetry,including his Fu-Poetry,four-word Poems as well as five-word poems,is escapist imagery. Ruan Ji has a kind of escapism complex which the paper talks over by case studies,i. e."Dongping fu"东平赋,four-word Poem IX and Poem XIII,and five-word Poem I and Poem LX X IX to find a new perspective to read Ruan Ji. This escapism complex is closely connected to Ruan Ji's unique mode of existence.