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  1. Dissertation / Habilitation ; Online: Synthetic Studies of Mn(III) Dipyrromethene Peroxynitrite Decomposition Catalysts by Maryam Imani Nejad, Doctor of Pharmacy

    Imani Nejad, Maryam

    2013  

    Abstract: One of the key contributors to the pathogenesis of various diseases is "nitroxidative stress," a condition caused by the overproduction of peroxynitrite (PN). Redox-active transition metal complexes, which function as PN decomposition catalysts (PNDCs), ... ...

    Abstract One of the key contributors to the pathogenesis of various diseases is "nitroxidative stress," a condition caused by the overproduction of peroxynitrite (PN). Redox-active transition metal complexes, which function as PN decomposition catalysts (PNDCs), can redirect oxidative potential of PN and are therefore able to reduce nitroxidative stress. Herein, synthetic methods for making polyfunctional trianionic dipyrromethene (DPM) ligand systems with an X-conjugation site for biomolecule coupling were studied. In addition, derivatives of PNDCs with electron donating groups were synthesized to vary the physicochemical properties and study the catalytic activity. Cross coupling of aryl bromide analogues of PNDCs with amines under Buchwald-Hartwig reaction conditions were investigated. Post-chelate conjugation of a variety of acetylene derivatives with an aryl bromide of the DPM backbone under Sonogashira coupling conditions was also studied. Finally, a succesful Suzuki cross-coupling of the key PNDC aryl bromide with a functionalized aryl boronic acid was demonstrated. Since both PNDCs and S1P antagonists are effective in treating inflammatory and neuropathic pain, hypothesized that a conjugate of our Mn(III)-DPM and a functional antagonist (FTY-720) of the sphingosine-1-phosphate receptor(s) may have synergistic activity. Synthetic routes for preparing two prototype analogues via the X-conjugation site chemistry were also developed.
    Schlagwörter Organic chemistry|Pharmacy sciences
    Thema/Rubrik (Code) 540
    Sprache ENG
    Erscheinungsdatum 2013-01-01 00:00:01.0
    Verlag Southern Illinois University at Edwardsville
    Erscheinungsland us
    Dokumenttyp Dissertation / Habilitation ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  2. Artikel ; Online: Two-step discriminant analysis based multi-view polarimetric SAR image classification with high confidence.

    Imani, Maryam

    Scientific reports

    2022  Band 12, Heft 1, Seite(n) 5984

    Abstract: Polarimetric synthetic aperture radar (PolSAR) image classification is a hot topic in remote sensing field. Although recently many deep learning methods such as convolutional based networks have provided great success in PolSAR image classification, but ... ...

    Abstract Polarimetric synthetic aperture radar (PolSAR) image classification is a hot topic in remote sensing field. Although recently many deep learning methods such as convolutional based networks have provided great success in PolSAR image classification, but they need a high volume of labeled samples, which are not usually available in practice, or they cause a high computational burden for implementation. In this work, instead of spending cost for network training, the inherent nature of PolSAR image is used for generation of convolutional kernels for extraction of deep and robust features. Moreover, extraction of diverse scattering characteristics contained in the coherency matrix of PolSAR and fusion of their output classification results with a high confidence have high impact in providing a reliable classification map. The introduced method called discriminative features based high confidence classification (DFC) utilizes several approaches to deal with difficulties of PolSAR image classification. It uses a multi-view analysis to generate diverse classification maps with different information. It extracts deep polarimetric-spatial features, consistent and robust with respect to the original PolSAR data, by applying several pre-determined convolutional filters selected from the important regions of image. Convolutional kernels are fixed without requirement to be learned. The important regions are determined with selecting the key points of image. In addition, a two-step discriminant analysis method is proposed to reduce dimensionality and result in a feature space with minimum overlapping and maximum class separability. Eventually, a high confidence decision fusion is implemented to find the final classification map. Impact of multi-view analysis, selection of important regions as fixed convolutional kernels, two-step discriminant analysis and high confidence decision fusion are individually assessed on three real PolSAR images in different sizes of training sets. For example, the proposed method achieves 96.40% and 98.72% overall classification accuracy by using 10 and 100 training samples per class, respectively in L-band Flevoland image acquired by AIRSAR. Generally, the experiments show high efficiency of DFC compared to several state-of-the-art methods especially for small sample size situations.
    Sprache Englisch
    Erscheinungsdatum 2022-04-08
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-022-09871-w
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  3. Artikel ; Online: Two-step discriminant analysis based multi-view polarimetric SAR image classification with high confidence

    Maryam Imani

    Scientific Reports, Vol 12, Iss 1, Pp 1-

    2022  Band 13

    Abstract: Abstract Polarimetric synthetic aperture radar (PolSAR) image classification is a hot topic in remote sensing field. Although recently many deep learning methods such as convolutional based networks have provided great success in PolSAR image ... ...

    Abstract Abstract Polarimetric synthetic aperture radar (PolSAR) image classification is a hot topic in remote sensing field. Although recently many deep learning methods such as convolutional based networks have provided great success in PolSAR image classification, but they need a high volume of labeled samples, which are not usually available in practice, or they cause a high computational burden for implementation. In this work, instead of spending cost for network training, the inherent nature of PolSAR image is used for generation of convolutional kernels for extraction of deep and robust features. Moreover, extraction of diverse scattering characteristics contained in the coherency matrix of PolSAR and fusion of their output classification results with a high confidence have high impact in providing a reliable classification map. The introduced method called discriminative features based high confidence classification (DFC) utilizes several approaches to deal with difficulties of PolSAR image classification. It uses a multi-view analysis to generate diverse classification maps with different information. It extracts deep polarimetric-spatial features, consistent and robust with respect to the original PolSAR data, by applying several pre-determined convolutional filters selected from the important regions of image. Convolutional kernels are fixed without requirement to be learned. The important regions are determined with selecting the key points of image. In addition, a two-step discriminant analysis method is proposed to reduce dimensionality and result in a feature space with minimum overlapping and maximum class separability. Eventually, a high confidence decision fusion is implemented to find the final classification map. Impact of multi-view analysis, selection of important regions as fixed convolutional kernels, two-step discriminant analysis and high confidence decision fusion are individually assessed on three real PolSAR images in different sizes of training sets. For example, the proposed method ...
    Schlagwörter Medicine ; R ; Science ; Q
    Thema/Rubrik (Code) 006
    Sprache Englisch
    Erscheinungsdatum 2022-04-01T00:00:00Z
    Verlag Nature Portfolio
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  4. Artikel: Automatic diagnosis of coronavirus (COVID-19) using shape and texture characteristics extracted from X-Ray and CT-Scan images.

    Imani, Maryam

    Biomedical signal processing and control

    2021  Band 68, Seite(n) 102602

    Abstract: Automatic diagnosis of coronavirus (COVID-19) is studied in this research. Deep learning methods especially convolutional neural networks (CNNs) have shown great success in COVID-19 diagnosis in recent works. But they are efficient when the depth of ... ...

    Abstract Automatic diagnosis of coronavirus (COVID-19) is studied in this research. Deep learning methods especially convolutional neural networks (CNNs) have shown great success in COVID-19 diagnosis in recent works. But they are efficient when the depth of network is high enough. However, the use of a deep network requires a sufficiently large training set, which is not available in practice. From the other hand, the use of a shallow CNN may not provide superior results because it is not able to rich feature extraction due to lacking enough convolutional layers. To deal with this difficulty, the contextual features reduced by convolutional filters (CFRCF) is proposed in this work. CFRCF extracts shape and textural features as contextual feature maps from the chest X-ray radiographs and abdominal computed tomography (CT) images. Morphological operators, Gabor filter banks and attribute filters are used for contextual feature extraction. Then, two convolutional filters are applied to the contextual feature cube to extract the nonlinear sub-features and hidden relationships among the contextual features. Finally, a fully connected layer is used to produce a reduced feature vector which is fed to a classifier. Support vector machine and random forest are used as classifier. The experimental results show the superior performance of the proposed method from the recognition accuracy and running time point of view using limited training samples. More than 76% and 94% overall classification accuracy is obtained by the proposed method in CT scan and X-ray images datasets, respectively.
    Sprache Englisch
    Erscheinungsdatum 2021-04-02
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 2241886-6
    ISSN 1746-8108 ; 1746-8094
    ISSN (online) 1746-8108
    ISSN 1746-8094
    DOI 10.1016/j.bspc.2021.102602
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  5. Artikel ; Online: PolSAR Classification Using Contextual Based Locality Preserving Projection and Guided Filtering

    Maryam Imani

    International Journal of Information and Communication Technology Research, Vol 13, Iss 2, Pp 29-

    2021  Band 38

    Abstract: Contextual feature extraction is studied for polarimetric synthetic aperture radar (PolSAR) image classification in this work. The contextual locality preserving projection (CLPP) method is proposed for generation of contextual feature cubes using ... ...

    Abstract Contextual feature extraction is studied for polarimetric synthetic aperture radar (PolSAR) image classification in this work. The contextual locality preserving projection (CLPP) method is proposed for generation of contextual feature cubes using limited training samples. The local information in neighborhood regions is used to extend the training set by including the spatial information. Then, a supervised transform is applied to the polarimetric-contextual feature cube to reduce the data dimensionality while preserves the local structures and settles the samples belonging to the same class close together. Finally, a guided filter is applied to the classification map to degrade the speckle noise. The classification results on two real L-band PolSAR data from AIRSAR show superior performance of CLPP for PolSAR classification in small sample size situations.
    Schlagwörter locality preserving projection ; spatial feature extraction ; classification ; polarization ; guided filter ; Information technology ; T58.5-58.64 ; Telecommunication ; TK5101-6720 ; Electronic computers. Computer science ; QA75.5-76.95
    Thema/Rubrik (Code) 004
    Sprache Englisch
    Erscheinungsdatum 2021-06-01T00:00:00Z
    Verlag Iran Telecom Research Center
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  6. Artikel: Nearest polarimetric and spatial neighbours for feature space projection and guidance image-based spatial filtering for PolSAR image classification

    Imani, Maryam

    Remote sensing letters. 2022 Apr. 03, v. 13, no. 4

    2022  

    Abstract: A feature space projection based on the nearest polarimetric and spatial neighbours is proposed for polarimetric synthetic aperture radar (PolSAR) images. The objective function is designed such that increases the class discrimination while preserves the ...

    Abstract A feature space projection based on the nearest polarimetric and spatial neighbours is proposed for polarimetric synthetic aperture radar (PolSAR) images. The objective function is designed such that increases the class discrimination while preserves the contextual properties. Each polarimetric or spatial neighbour is contributed proportional to with its Wishart distance to the given pixel. A guidance image, which involves all polarimetric channels, is also introduced for spatial filtering of the initial classification map, which is efficient for improving the final classification map. The proposed method shows high performance for PolSAR image classification using limited training samples.
    Schlagwörter image analysis ; polarimetry ; synthetic aperture radar
    Sprache Englisch
    Erscheinungsverlauf 2022-0403
    Umfang p. 406-417.
    Erscheinungsort Taylor & Francis
    Dokumenttyp Artikel
    ISSN 2150-7058
    DOI 10.1080/2150704X.2022.2033873
    Datenquelle NAL Katalog (AGRICOLA)

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  7. Artikel: Median-mean line based collaborative representation for PolSAR terrain classification

    Imani, Maryam

    National Authority of Remote Sensing & Space Science The Egyptian Journal of Remote Sensing and Space Sciences (Online). 2022 Feb., v. 25, no. 1

    2022  

    Abstract: A collaborative representation (CR) based method is proposed for polarimetric synthetic aperture radar (PolSAR) data classification in this work. Although CR can well smooth the PolSAR data and remove the speckle noise but it may degrade the class ... ...

    Abstract A collaborative representation (CR) based method is proposed for polarimetric synthetic aperture radar (PolSAR) data classification in this work. Although CR can well smooth the PolSAR data and remove the speckle noise but it may degrade the class boundaries in heterogeneous regions. To deal with this difficulty, a weighted CR with considering the edge information is proposed. In addition, to further utilize the contextual information, the residual terms of CR are smoothed while the misfitting terms are minimized. Moreover, the median-mean line metric is used to degrade the outlier effects with involving interpolation or extrapolation of mean and median values. The proposed method called median-mean line based CR (MMLCR) leads to superior PolSAR classification results particularly when a limited number of training samples is available. For example, 94.79% overall classification accuracy is achieved for classification of the Flevoland dataset containing 15 classes with just using 10 training samples per class.
    Schlagwörter data collection ; landscapes ; polarimetry ; synthetic aperture radar
    Sprache Englisch
    Erscheinungsverlauf 2022-02
    Umfang p. 281-288.
    Erscheinungsort Elsevier B.V.
    Dokumenttyp Artikel
    ISSN 1110-9823
    DOI 10.1016/j.ejrs.2022.01.011
    Datenquelle NAL Katalog (AGRICOLA)

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  8. Artikel ; Online: Entropy/anisotropy/alpha based 3DGabor filter bank for PolSAR image classification

    Imani, Maryam

    Geocarto International. 2022 Dec. 13, v. 37, no. 27 p.18491-18519

    2022  

    Abstract: There are two types of features in a polarimetric synthetic aperture radar (PolSAR) image: 1-physical scattering characteristics of radar, and 2-geometric and texture properties. To handle the 3D nature of PolSAR image, a revised 3DGabor filter bank is ... ...

    Abstract There are two types of features in a polarimetric synthetic aperture radar (PolSAR) image: 1-physical scattering characteristics of radar, and 2-geometric and texture properties. To handle the 3D nature of PolSAR image, a revised 3DGabor filter bank is proposed here. Although the 3DGabor filter can explore the interaction between three dimensions of the PolSAR cube, but it does not utilize the physical information of radar including the scattering mechanism. To deal with this issue, the physical parameters of the entropy/anisotropy/alpha decomposition theory are used to revise the 3DGabor filter. The output is joint texture and physical features of the PolSAR cube. These features are highly discriminative such that they can provide high accurate classification maps specially by using limited training samples. The experimental results on three PolSAR images show better performance of the proposed method with respect to several competitors with a significant difference from the statistical point of view.
    Schlagwörter anisotropy ; entropy ; image analysis ; polarimetry ; synthetic aperture radar ; texture ; Entropy/anisotropy/alpha ; 3DGabor filter ; classification ; PolSAR
    Sprache Englisch
    Erscheinungsverlauf 2022-1213
    Umfang p. 18491-18519.
    Erscheinungsort Taylor & Francis
    Dokumenttyp Artikel ; Online
    ISSN 1752-0762
    DOI 10.1080/10106049.2022.2142963
    Datenquelle NAL Katalog (AGRICOLA)

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  9. Artikel: Low frequency and radar’s physical based features for improvement of convolutional neural networks for PolSAR image classification

    Imani, Maryam

    National Authority of Remote Sensing & Space Science The Egyptian Journal of Remote Sensing and Space Sciences (Online). 2022 Feb., v. 25, no. 1

    2022  

    Abstract: Although various deep neural networks such as convolutional neural networks (CNNs) have been suggested for classification of polarimetric synthetic aperture radar (PolSAR) images, but, they have several deficiencies. CNNs have weakness in producing ... ...

    Abstract Although various deep neural networks such as convolutional neural networks (CNNs) have been suggested for classification of polarimetric synthetic aperture radar (PolSAR) images, but, they have several deficiencies. CNNs have weakness in producing classification maps with reduced noise and also are disabled in extraction of polarimetric/scattering information to explore the physical characteristics of the radar image. A deep neural network based on convolutional blocks is proposed for PolSAR image classification in this work that deals with the above difficulties. The low frequency components of the PolSAR image are added to the output of convolutional blocks to help the network to learn noise reduction. Moreover, eight fuzzy clustering maps obtained by the polarimetric entropy and averaged alpha angle are extracted as radar’s physical feature maps which concatenated with the spatial features extracted by convolutional blocks. So, the proposed network while learns to reduce the speckle noise, learns to simultaneously extract the spatial-physical characteristics of the PolSAR cube. The experiments on two real PolSAR datasets show superior performance of the proposed network compared to CNN, residual network and some other well-done networks.
    Schlagwörter data collection ; entropy ; image analysis ; polarimetry ; synthetic aperture radar
    Sprache Englisch
    Erscheinungsverlauf 2022-02
    Umfang p. 55-62.
    Erscheinungsort Elsevier B.V.
    Dokumenttyp Artikel
    ISSN 1110-9823
    DOI 10.1016/j.ejrs.2021.12.007
    Datenquelle NAL Katalog (AGRICOLA)

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  10. Artikel ; Online: Scattering and contextual features fusion using a complex multi-scale decomposition for polarimetric SAR image classification

    Imani, Maryam

    Geocarto International. 2022 Dec. 13, v. 37, no. 27 p.17216-17241

    2022  

    Abstract: Polarimetric synthetic aperture radar (PolSAR) images contain rich information about back-scattering and physical characteristics of targets. So, they have high ability for discrimination of different land cover classes. The aim of this research is to ... ...

    Abstract Polarimetric synthetic aperture radar (PolSAR) images contain rich information about back-scattering and physical characteristics of targets. So, they have high ability for discrimination of different land cover classes. The aim of this research is to introduce an efficient method for PolSAR image classification. Extraction of both scattering and contextual features is important for class discrimination. Therefore, the scattering and contextual feature fusion (SCF) method is proposed to fuse the extracted polarimetric and morphological features through applying a complex multi-scale decomposition. The dual tree complex wavelet transform is used to decompose each scattering feature map into its details and approximate components. The contextual feature maps are decomposed in a similar way. Then, details of two kinds of feature maps are fused region by region. This process is also done for the approximation components containing the low frequency information. The result will be a high dimensional fused feature space. The principal discriminant analysis (PDA) is proposed to reduce the data dimensionality with discarding noisy components and increasing the class discrimination. The extracted features are then fed into a simple classifier to obtain the classification map. Three L-band PolSAR images acquired by airborne synthetic aperture radar (AIRSAR) and electronically steered array radar (ESAR) are used for doing experiments. The SCF method shows superior classification results with respect to several state-of-the-art PolSAR classifiers. For example, for the Flevoland dataset containing 15 classes, without applying post processing, the SCF method results in 95.22% overall accuracy compared to 2DCNN with 91.84% and 3DCNN with 93.94% overall accuracy. With applying post processing, the classification results of SCF, 2DCNN and 3DCNN are increased to 99.55%, 98.61% and 99.09%, respectively.
    Schlagwörter data collection ; discriminant analysis ; image analysis ; land cover ; polarimetry ; synthetic aperture radar ; trees ; wavelet ; Dual tree complex wavelet transform ; feature fusion ; polarimetric SAR ; classification
    Sprache Englisch
    Erscheinungsverlauf 2022-1213
    Umfang p. 17216-17241.
    Erscheinungsort Taylor & Francis
    Dokumenttyp Artikel ; Online
    ISSN 1752-0762
    DOI 10.1080/10106049.2022.2123961
    Datenquelle NAL Katalog (AGRICOLA)

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