MATLAB software and optimal complete subgraph algorithm were used to extract and reveal the microsatellite distribution features in the complete genomes of the tobacco vein clearing virus （NC-003 378.1） from the NCB...MATLAB software and optimal complete subgraph algorithm were used to extract and reveal the microsatellite distribution features in the complete genomes of the tobacco vein clearing virus （NC-003 378.1） from the NCBI database.The results showed that the repetitions number and their location of the N-base group has been extracted and displayed.The largest repetitions of N-base group in the complete genomes of the tobacco vein clearing virus was decreased as the exponential function with the increasing of N.The method used in this study could be applied to the extraction and revealing of the microsatellite distribution features in the complete genomes of other viruses,thereby provided a basis for the research of the structure and the law of function,inheritance and variation by the using of the microsatellite distribution features.展开更多
Content-based satellite image registration is a difficult issue in the fields of remote sensing and image processing. The difficulty is more significant in the case of matching multisource remote sensing images which ...Content-based satellite image registration is a difficult issue in the fields of remote sensing and image processing. The difficulty is more significant in the case of matching multisource remote sensing images which suffer from illumination, rotation, and source differences. The scale-invariant feature transform （SIFT） algorithm has been used successfully in satellite image registration problems. Also, many researchers have applied a local SIFT descriptor to improve the image retrieval process. Despite its robustness, this algorithm has some difficulties with the quality and quantity of the extracted local feature points in multisource remote sensing. Furthermore, high dimensionality of the local features extracted by SIFT results in time-consuming computational processes alongside high storage requirements for saving the relevant information, which are important factors in content-based image retrieval （CBIR） applications. In this paper, a novel method is introduced to transform the local SIFT features to global features for multisource remote sensing. The quality and quantity of SIFT local features have been enhanced by applying contrast equalization on images in a pre-processing stage. Considering the local features of each image in the reference database as a separate class, linear discriminant analysis （LDA） is used to transform the local features to global features while reducing di- mensionality of the feature space. This will also significantly reduce the computational time and storage required. Applying the trained kernel on verification data and mapping them showed a successful retrieval rate of 91.67% for test feature points.展开更多
A study of[S Ⅲ]λλ9096,9532 emitters at z=1.34 and 1.23 is presented using our deep narrow-band H2S 1(centered at 2.13μm)imaging survey of the Extended Chandra Deep Field South(ECDFS).We combine our data with multi...A study of[S Ⅲ]λλ9096,9532 emitters at z=1.34 and 1.23 is presented using our deep narrow-band H2S 1(centered at 2.13μm)imaging survey of the Extended Chandra Deep Field South(ECDFS).We combine our data with multi-wavelength data of ECDFS to build up spectral energy distributions(SEDs)from the U to the Ks-band for emitter candidates selected with strong excess in H2S 1 Ks and derive photometric redshifts,line luminosities,stellar masses and extinction.A sample of 14[S Ⅲ]emitters are identified with H2S 1<22.8 and Ks<24.8(AB)over 381 arcmin2area,having[S Ⅲ]line luminosity L[S Ⅲ]=~1041.5 42.6erg s 1.None of the[S Ⅲ]emitters is found to have X-ray counterpart in the deepest Chandra 4 Ms observation,suggesting that they are unlikely powered by AGNs.The HST/ACS F606W and HST/WFC3 F160W images show their rest-frame UV and optical morphologies.About half of the[S Ⅲ]emitters are mergers and at least one third are disk-type galaxies.Nearly all[S Ⅲ]emitters exhibit a prominent Balmer break in their SEDs,indicating the presence of a significant post-starburst component.Taken together,our results imply that both shock heating in post-starburst and photoionization caused by young massive stars are likely to excite strong[S Ⅲ]emission lines.We conclude that the[S Ⅲ]emitters in our sample are dominated by star-forming galaxies(SFGs)with stellar mass 8.7<log(M/M⊙)<9.9.展开更多
基金Supported by the Eleventh Five-year Development Planning Project for Instructional Science in Hubei Province (2006B131)~~
文摘MATLAB software and optimal complete subgraph algorithm were used to extract and reveal the microsatellite distribution features in the complete genomes of the tobacco vein clearing virus （NC-003 378.1） from the NCBI database.The results showed that the repetitions number and their location of the N-base group has been extracted and displayed.The largest repetitions of N-base group in the complete genomes of the tobacco vein clearing virus was decreased as the exponential function with the increasing of N.The method used in this study could be applied to the extraction and revealing of the microsatellite distribution features in the complete genomes of other viruses,thereby provided a basis for the research of the structure and the law of function,inheritance and variation by the using of the microsatellite distribution features.
文摘Content-based satellite image registration is a difficult issue in the fields of remote sensing and image processing. The difficulty is more significant in the case of matching multisource remote sensing images which suffer from illumination, rotation, and source differences. The scale-invariant feature transform （SIFT） algorithm has been used successfully in satellite image registration problems. Also, many researchers have applied a local SIFT descriptor to improve the image retrieval process. Despite its robustness, this algorithm has some difficulties with the quality and quantity of the extracted local feature points in multisource remote sensing. Furthermore, high dimensionality of the local features extracted by SIFT results in time-consuming computational processes alongside high storage requirements for saving the relevant information, which are important factors in content-based image retrieval （CBIR） applications. In this paper, a novel method is introduced to transform the local SIFT features to global features for multisource remote sensing. The quality and quantity of SIFT local features have been enhanced by applying contrast equalization on images in a pre-processing stage. Considering the local features of each image in the reference database as a separate class, linear discriminant analysis （LDA） is used to transform the local features to global features while reducing di- mensionality of the feature space. This will also significantly reduce the computational time and storage required. Applying the trained kernel on verification data and mapping them showed a successful retrieval rate of 91.67% for test feature points.
基金This research uses data obtained through the Telescope Access Program(TAP),which is funded by the National Astronomical Observatories and the Special Fund for Astronomy from the Ministry of Financesupported by the National Basic Research Program of China(GrantNo.2013CB834900)the National Natural Science Foundation of China(Grant No.11063002)
文摘A study of[S Ⅲ]λλ9096,9532 emitters at z=1.34 and 1.23 is presented using our deep narrow-band H2S 1(centered at 2.13μm)imaging survey of the Extended Chandra Deep Field South(ECDFS).We combine our data with multi-wavelength data of ECDFS to build up spectral energy distributions(SEDs)from the U to the Ks-band for emitter candidates selected with strong excess in H2S 1 Ks and derive photometric redshifts,line luminosities,stellar masses and extinction.A sample of 14[S Ⅲ]emitters are identified with H2S 1<22.8 and Ks<24.8(AB)over 381 arcmin2area,having[S Ⅲ]line luminosity L[S Ⅲ]=~1041.5 42.6erg s 1.None of the[S Ⅲ]emitters is found to have X-ray counterpart in the deepest Chandra 4 Ms observation,suggesting that they are unlikely powered by AGNs.The HST/ACS F606W and HST/WFC3 F160W images show their rest-frame UV and optical morphologies.About half of the[S Ⅲ]emitters are mergers and at least one third are disk-type galaxies.Nearly all[S Ⅲ]emitters exhibit a prominent Balmer break in their SEDs,indicating the presence of a significant post-starburst component.Taken together,our results imply that both shock heating in post-starburst and photoionization caused by young massive stars are likely to excite strong[S Ⅲ]emission lines.We conclude that the[S Ⅲ]emitters in our sample are dominated by star-forming galaxies(SFGs)with stellar mass 8.7<log(M/M⊙)<9.9.
