With tissue cultured-seedlings of Rhododendron chrysanthum Pall. in Changbai Mountain as test material, the effect of EMS treatment on the heat toler- ance of R. chrysanthum, as well as the possible heat tolerance mec...With tissue cultured-seedlings of Rhododendron chrysanthum Pall. in Changbai Mountain as test material, the effect of EMS treatment on the heat toler- ance of R. chrysanthum, as well as the possible heat tolerance mechanism, was in- vestigated in this study so as to lay a foundation for the popularization, application and germplasm resource innovation of R. chrysanthum. The results showed that when the leaves of the tissue cultured seedlings were treated with medium with 0.1% of EMS for 2 d, the survival rate of the leaves was 48.92%, thus the con- centration of EMS was close to the semi-lethal dose, and the EMS concentration and treatment time could be used as screening conditions for heat-tolerant mutants. The plantlets regenerated from EMS-treated leaves were treated with different tem- peratures, and related physiological indicators were determined. The results showed that the chlorophyll content, MDA content, Pro content, SOD activity, POD activity and soluble sugar content of regeneration plantlets in the treatment group were sig- nificantly different from those in the control group. At the same temperature, the chlorophyll content, soluble sugar content, Pro content, SOD activity and POD ac- tivity were significantly higher and the MDA content was significantly lower in the treatment group compared with the control. In conclusion, EMS treatment improved the heat tolerance of tissue-cultured R. chrysanthum seedlings.展开更多
This paper reports the rationale and methods of DNA extraction and purification from nine species of Compositae and four commercial drugs of corresponding plant Elephantopus scaber. The comparison of three methods: Cs...This paper reports the rationale and methods of DNA extraction and purification from nine species of Compositae and four commercial drugs of corresponding plant Elephantopus scaber. The comparison of three methods: CsCl gradient, CTAB/CsCl gradient and CTAB miniprep extraction by yield, purity and factors affecting PCR was carried out. In conclusion, CTAB miniprep method provides a rapid, effective, economic approach for isolating genomic DNA for Chinese drug identification by genomic fingerprints.展开更多
In the non-contact measurement using the linear structured light(LSL),the extraction precision of the light stripe center directly affects the measurement accuracy of the whole detection system.To solve the problem th...In the non-contact measurement using the linear structured light(LSL),the extraction precision of the light stripe center directly affects the measurement accuracy of the whole detection system.To solve the problem that general algorithms cannot accurately extract the center of the light stripe with the uneven width and unstable greyvalue distribution,an adaptive optimization method is proposed.In this method,the stripe region is firstly segmented,and the widths of the laser stripe are calculated by boundary detection.The initial stripe center points are computed by the quadratic weighted grayscale centroid method based on the self-adaptive stripe width.After that,these center points are optimized according to the determined slope threshold.The sub-pixel coordinates of these center points are recalculated.Detailed analysis is also performed in line with the proposed evaluation index of the extraction algorithm.The experimental results show that the mean square error of extracted center points is only 0.1 pixel,meaning that the accuracy of laser stripe center extraction is improved significantly by the method.Furthermore,the method can run effectively at a relatively low computational time cost,and can demonstrate great robustness as well.展开更多
This paper introduces a new concept of "State Representation Methodology (SRM)" which is a kind of bridge condition assessment method for structural health monitoring system (SHM). There are many methods for sys...This paper introduces a new concept of "State Representation Methodology (SRM)" which is a kind of bridge condition assessment method for structural health monitoring system (SHM). There are many methods for system identification from the simplicity comparison of damage index to the complicated statistical pattern recognition algorithms in SHM. In these methods, modal analysis and parameters identification or many defined indices are common-used for extracting the dynamic or static characteristics of a system. However, there is a common problem: due to the complexity of a large size system with high-order nonlinear characteristics and severe environment interference, it is impossible to extract and quantify exactly these modal parameters or system parameters or indices as the feature vectors of a system in damage detection in an easy way. The SRM considered a more general theory for the non-parametric description of system state.展开更多
The amplified fragment length polymorphic DNA (AFLP) technique was adopted to estimate the population genetic polymorphism among 30 sporophytes of Laminaria japonica collected from a cultivating farm in Rongcheng,Chin...The amplified fragment length polymorphic DNA (AFLP) technique was adopted to estimate the population genetic polymorphism among 30 sporophytes of Laminaria japonica collected from a cultivating farm in Rongcheng,China.Three methods were used for genomic DNA extraction from Laminaria japonica sporophyte and only the products obtained using the improved genomic DNA extraction kit method proved qualified for AFLP analysis.The parameters of the method were optimized.Samples of forty milligrams and the cell lysis time of 120 min were suggested to replace the parameters recommended by the manufacturer.Thirty individuals of Laminaria japonica from the same cultivating site were investigated using one pair of selective primers.A total of 21 loci were obtained and 17 of them were polymorphic.The mean percent age of polymorphic loci of this population was 80.95%.The Nei's gene diversity (H) within this population was 0.3028 and the average Shannon's Information index (I) was 0.4498.A genetic distance matrix among different individuals was constructed as well.Through this study,an applicable AFLP genetic analysis working system for Laminaria japonica sporophyte was established.The results of this research also revealed a high level of genetic diversity within the studied population.展开更多
MODIS-EVI time series data from 2000 to 2009 in Chongqing were selected for this study.By the use of best index slope extraction (BISE) method for cloud elimination,analysis on the change vector of EVI time series d...MODIS-EVI time series data from 2000 to 2009 in Chongqing were selected for this study.By the use of best index slope extraction (BISE) method for cloud elimination,analysis on the change vector of EVI time series data were conducted to investigate the EVI response on drought; then,four typical regions were selected to study the relationship between precipitation,temperature and EVI when the sever drought occurred in 2006; finally,based on the time series of vegetation condition index (VCI) and precipitation abnormity percentage,the temporal and spatial distributions of drought were studied.The results showed that,the EVI value of the summer in 2006 was significantly lower than the average EVI at the corresponding period of the other years in Chongqing.In addition,summer drought occurred mainly during the hot and dry weather.Except the southeast area,most of the other regions in Chongqing were all under severe drought.展开更多
Distribution of monsoon forests is important for the research of carbon and water cycles in the tropical regions. In this paper, a simple approach is proposed to map monsoon forests using the Normalized Difference Veg...Distribution of monsoon forests is important for the research of carbon and water cycles in the tropical regions. In this paper, a simple approach is proposed to map monsoon forests using the Normalized Difference Vegetation lndex (NDVI) derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) data. Owing to the high contrast of greenness between wet season and dry season, the monsoon forest can be easily discriminated from other forests by combining the maximum and minimum annual NDVI. The MODIS-based monsoon forest maps (MODMF) from 2000 to 2009 are derived and evaluated using the ground-truth dataset. The MODMF achieves an average producer accuracy of 80.0% and the Kappa statistic of 0.719. The variability of MODMF among different years is compared with that calculated from MODIS land cover products (MCD 12Q 1). The results show that the coefficient of variation of total monsoon forest area in MODMF is 7.3%, which is far lower than that in MCD12Q1 with 24.3%. Moreover, the pixels in MODMv which can be identified for 7 to 9 times between 200l and 2009 account for 53.1%, while only 7.9% ofMCD12QI pixels have this frequency. Additionally, the monsoon forest areas estimated in MODMF, Global Land Cover 2000 (GLC2000), MCDI2Q1 and University of Maryland (UMD) products are compared with the statistical dataset at national level, which reveals that MODMv has the highest R^2 of 0.95 and the lowest RMSE of 14 014 km^2. This algorithm is simple but reliable for mapping the monsoon forests without complex classification techniques.展开更多
Remotely sensing images are now available for monitoring vegetation dynamics over large areas.In this paper,an improved logistic model that combines double logistic model and global function was developed.Using this m...Remotely sensing images are now available for monitoring vegetation dynamics over large areas.In this paper,an improved logistic model that combines double logistic model and global function was developed.Using this model with SPOT/NDVI data,three key vegetation phenology metrics,the start of growing season (SOS),the end of growing season (EOS) and the length of growing season (LOS),were extracted and mapped in the Changbai Mountains,and the relationship between the key phenology metrics and elevation were established.Results show that average SOS of forest,cropland and grassland in the Changbai Mountains are on the 119th,145th,and 133rd day of year,respectively.The EOS of forest and grassland are similar,with the average on the 280th and 278th,respectively.In comparison,average EOS of the cropland is relatively earlier.The LOS of forest is mainly from the 160th to 180th,that of the grassland extends from the 140th to the 160th,and that of cropland stretches from the 110th to the 130th.As the latitude increases for the same land cover in the study area,the SOS significantly delays and the EOS becomes earlier.The SOS delays approximately three days as the elevation increases 100 m in the areas with elevation higher than 900 m above sea level (a.s.l.).The EOS is slightly earlier as the elevation increases especially in the areas with elevation below 1200 m a.s.l.The LOS shortens approximately four days as the elevation increases 100 m in the areas with elevation higher than 900 m a.s.l.The relationships between vegetation phenology metrics and elevation may be greatly influenced by the land covers.Validation by comparing with the field data and previous research results indicates that the improved logistic model is reliable and effective for extracting vegetation phenology metrics.展开更多
Codfish is a kind of abyssal fish species with a great value in food industry. However, the flavor of codfish, especially the unpleasant odor, has caused serious problems in its processing. To accurately identify the ...Codfish is a kind of abyssal fish species with a great value in food industry. However, the flavor of codfish, especially the unpleasant odor, has caused serious problems in its processing. To accurately identify the volatile compounds in codfish, a combination of solid phase micro-extraction(SPME) method and simultaneous distillation extraction(SDE) method was used to extract the volatiles. Gas chromatography-mass spectrometry(GC-MS) along with Kovats indices(KI) and authentic standard compounds were used to identify the volatiles. The results showed that a total of 86 volatile compounds were identified in codfish, of them 24 were extracted by SDE, 69 compounds by SPME, and 10 compounds by both SDE and SPME. Seventy volatile compounds were found to have specific odors, of them 7 typical compounds contributed significantly to the flavor of codfish. Alcohols(i.e.,(E)-2-penten-1-ol and 2-octanol), esters(i.e., ethyl butyrate and methyl geranate), aldehydes(i.e., 2-dodecenal and pentadecanal) contributed the most to fresh flavor while nitrogen compounds, sulphur compounds, furans, as well as some ketones(i.e., 2-hydroxy-3-pentanone) brought unpleasant odor, such as fishy and earthy odor. It was indicated that the combination of multiple extraction methods and GC-MS analysis can enhance the accuracy of identification, and provide a reference for the further study on flavor of aquatic products.展开更多
A semi-reference image quality assessment metric based on similarity measurement for synthesized virtual viewpoint image (VVI) in free-viewpoint television system (FFV) is proposed in this paper. The key point of ...A semi-reference image quality assessment metric based on similarity measurement for synthesized virtual viewpoint image (VVI) in free-viewpoint television system (FFV) is proposed in this paper. The key point of the proposed metric is taking resemblant information between VVI and its neighbor view images for quality assessment to make our metric to be extended to multi-semi-reference image quality assessment easily. The proposed metric first extracts impact factors from image features, then combines an image synthesis technique and similarity functions, in which, disparity information are taken into account for registering the resemblant regions. Experiments are divided into three phases. Phase I is to verify the validation of the proposed metric by taking impaired images and original reference into account. The experimental results show the agreement between evaluation scores and bio-characteristic of human visual system. Phase II shows the accordance with Phase I by taking neighbor view as reference. The proposed metric can be taken as a full reference one to evaluate the image quality even though the original reference is absent. Phase III is then performed to evaluate the quality of WI. Evaluation scores in the experimental results are able to evaluate the quality of VVI.展开更多
Singular point(SP)extraction is a key component in automatic fingerprint identification system(AFIS).A new method was proposed for fingerprint singular points extraction,based on orientation tensor field and Laurent s...Singular point(SP)extraction is a key component in automatic fingerprint identification system(AFIS).A new method was proposed for fingerprint singular points extraction,based on orientation tensor field and Laurent series.First,fingerprint orientation flow field was obtained,using the gradient of fingerprint image.With these gradients,fingerprint orientation tensor field was calculated.Then,candidate SPs were detected by the cross-correlation energy in multi-scale Gaussian space.The energy was calculated between fingerprint orientation tensor field and Laurent polynomial model.As a global descriptor,the Laurent polynomial coefficients were allowed for rotational invariance.Furthermore,a support vector machine(SVM)classifier was trained to remove spurious SPs,using cross-correlation coefficient as a feature vector.Finally,experiments were performed on Singular Point Detection Competition 2010(SPD2010)database.Compared to the winner algorithm of SPD2010 which has best accuracy of 31.90%,the accuracy of proposed algorithm is 45.34%.The results show that the proposed method outperforms the state-of-the-art detection algorithms by large margin,and the detection is invariant to rotational transformations.展开更多
In this work, a hybrid method is proposed to eliminate the limitations of traditional protein-protein interactions (PPIs) extraction methods, such as pattern learning and machine learning. Each sentence from the bio...In this work, a hybrid method is proposed to eliminate the limitations of traditional protein-protein interactions (PPIs) extraction methods, such as pattern learning and machine learning. Each sentence from the biomedical literature containing a protein pair describes a PPI which is predicted by first learning syntax patterns typical of PPIs from training corpus and then using their presence as features, along with bag-of-word features in a maximum entropy model. Tested on the BioCreAtIve corpus, the PPIs extraction method, which achieved a precision rate of 64%, recall rate of 60%, improved the performance in terms of F1 value by 11% compared with the component pure pattern- based and bag-of-word methods. The results on this test set were also compared with other three extraction methods and found to improve the performance remarkably.展开更多
Urban vegetation has been an important indicator for the evaluation of eco-cities, which is of great significance to promote eeo-city construction. We study and discuss the commonly used urban vegetation extrac-tion m...Urban vegetation has been an important indicator for the evaluation of eco-cities, which is of great significance to promote eeo-city construction. We study and discuss the commonly used urban vegetation extrac-tion methods. The extraction of vegetation points in this study is completed through mathematical statistics, mean-square error, successive differences and iterative algorithm which are based on the analysis of different spatial morphological characteristics in urban point clouds. Linyi, a city of Shandong Province in China, is se-lected as the study area to test this method and the result shows that the proposed method has a strong practicali- ty in urban vegetation point cloud extraction. Only 3D coordinate properties of the LiDAR point clouds are used in this method and it does not require additional information, for instance, return intensity, which makes the method more applicable and operable.展开更多
基金Supported by College Students’ Innovative Entrepreneurial Training Program 2016~~
文摘With tissue cultured-seedlings of Rhododendron chrysanthum Pall. in Changbai Mountain as test material, the effect of EMS treatment on the heat toler- ance of R. chrysanthum, as well as the possible heat tolerance mechanism, was in- vestigated in this study so as to lay a foundation for the popularization, application and germplasm resource innovation of R. chrysanthum. The results showed that when the leaves of the tissue cultured seedlings were treated with medium with 0.1% of EMS for 2 d, the survival rate of the leaves was 48.92%, thus the con- centration of EMS was close to the semi-lethal dose, and the EMS concentration and treatment time could be used as screening conditions for heat-tolerant mutants. The plantlets regenerated from EMS-treated leaves were treated with different tem- peratures, and related physiological indicators were determined. The results showed that the chlorophyll content, MDA content, Pro content, SOD activity, POD activity and soluble sugar content of regeneration plantlets in the treatment group were sig- nificantly different from those in the control group. At the same temperature, the chlorophyll content, soluble sugar content, Pro content, SOD activity and POD ac- tivity were significantly higher and the MDA content was significantly lower in the treatment group compared with the control. In conclusion, EMS treatment improved the heat tolerance of tissue-cultured R. chrysanthum seedlings.
文摘This paper reports the rationale and methods of DNA extraction and purification from nine species of Compositae and four commercial drugs of corresponding plant Elephantopus scaber. The comparison of three methods: CsCl gradient, CTAB/CsCl gradient and CTAB miniprep extraction by yield, purity and factors affecting PCR was carried out. In conclusion, CTAB miniprep method provides a rapid, effective, economic approach for isolating genomic DNA for Chinese drug identification by genomic fingerprints.
基金the National Natural Science Foundation of China(No.51975293)the Aeronautical Science Foundation of China(No.2019ZD052010)。
文摘In the non-contact measurement using the linear structured light(LSL),the extraction precision of the light stripe center directly affects the measurement accuracy of the whole detection system.To solve the problem that general algorithms cannot accurately extract the center of the light stripe with the uneven width and unstable greyvalue distribution,an adaptive optimization method is proposed.In this method,the stripe region is firstly segmented,and the widths of the laser stripe are calculated by boundary detection.The initial stripe center points are computed by the quadratic weighted grayscale centroid method based on the self-adaptive stripe width.After that,these center points are optimized according to the determined slope threshold.The sub-pixel coordinates of these center points are recalculated.Detailed analysis is also performed in line with the proposed evaluation index of the extraction algorithm.The experimental results show that the mean square error of extracted center points is only 0.1 pixel,meaning that the accuracy of laser stripe center extraction is improved significantly by the method.Furthermore,the method can run effectively at a relatively low computational time cost,and can demonstrate great robustness as well.
文摘This paper introduces a new concept of "State Representation Methodology (SRM)" which is a kind of bridge condition assessment method for structural health monitoring system (SHM). There are many methods for system identification from the simplicity comparison of damage index to the complicated statistical pattern recognition algorithms in SHM. In these methods, modal analysis and parameters identification or many defined indices are common-used for extracting the dynamic or static characteristics of a system. However, there is a common problem: due to the complexity of a large size system with high-order nonlinear characteristics and severe environment interference, it is impossible to extract and quantify exactly these modal parameters or system parameters or indices as the feature vectors of a system in damage detection in an easy way. The SRM considered a more general theory for the non-parametric description of system state.
基金funded by the ‘908’ Marine Survey Project of Shandong Province (SD-908-01-01-05.06)
文摘The amplified fragment length polymorphic DNA (AFLP) technique was adopted to estimate the population genetic polymorphism among 30 sporophytes of Laminaria japonica collected from a cultivating farm in Rongcheng,China.Three methods were used for genomic DNA extraction from Laminaria japonica sporophyte and only the products obtained using the improved genomic DNA extraction kit method proved qualified for AFLP analysis.The parameters of the method were optimized.Samples of forty milligrams and the cell lysis time of 120 min were suggested to replace the parameters recommended by the manufacturer.Thirty individuals of Laminaria japonica from the same cultivating site were investigated using one pair of selective primers.A total of 21 loci were obtained and 17 of them were polymorphic.The mean percent age of polymorphic loci of this population was 80.95%.The Nei's gene diversity (H) within this population was 0.3028 and the average Shannon's Information index (I) was 0.4498.A genetic distance matrix among different individuals was constructed as well.Through this study,an applicable AFLP genetic analysis working system for Laminaria japonica sporophyte was established.The results of this research also revealed a high level of genetic diversity within the studied population.
基金Supported by Foundation for Science and Technology Research Project of Chongqing (2009AC0125)Natural Science Foundation of Chongqing (2008BB1379)The Major Project of Ministry of Science and Technology," Science and Technology Action for Western Development" (2005BA901A01)~~
文摘MODIS-EVI time series data from 2000 to 2009 in Chongqing were selected for this study.By the use of best index slope extraction (BISE) method for cloud elimination,analysis on the change vector of EVI time series data were conducted to investigate the EVI response on drought; then,four typical regions were selected to study the relationship between precipitation,temperature and EVI when the sever drought occurred in 2006; finally,based on the time series of vegetation condition index (VCI) and precipitation abnormity percentage,the temporal and spatial distributions of drought were studied.The results showed that,the EVI value of the summer in 2006 was significantly lower than the average EVI at the corresponding period of the other years in Chongqing.In addition,summer drought occurred mainly during the hot and dry weather.Except the southeast area,most of the other regions in Chongqing were all under severe drought.
基金National Natural Science Foundation of China(No.41171285)Research and Development Special Fund for Public Welfare Industry(Meteorology)of China(No.GYHY201106014)
文摘Distribution of monsoon forests is important for the research of carbon and water cycles in the tropical regions. In this paper, a simple approach is proposed to map monsoon forests using the Normalized Difference Vegetation lndex (NDVI) derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) data. Owing to the high contrast of greenness between wet season and dry season, the monsoon forest can be easily discriminated from other forests by combining the maximum and minimum annual NDVI. The MODIS-based monsoon forest maps (MODMF) from 2000 to 2009 are derived and evaluated using the ground-truth dataset. The MODMF achieves an average producer accuracy of 80.0% and the Kappa statistic of 0.719. The variability of MODMF among different years is compared with that calculated from MODIS land cover products (MCD 12Q 1). The results show that the coefficient of variation of total monsoon forest area in MODMF is 7.3%, which is far lower than that in MCD12Q1 with 24.3%. Moreover, the pixels in MODMv which can be identified for 7 to 9 times between 200l and 2009 account for 53.1%, while only 7.9% ofMCD12QI pixels have this frequency. Additionally, the monsoon forest areas estimated in MODMF, Global Land Cover 2000 (GLC2000), MCDI2Q1 and University of Maryland (UMD) products are compared with the statistical dataset at national level, which reveals that MODMv has the highest R^2 of 0.95 and the lowest RMSE of 14 014 km^2. This algorithm is simple but reliable for mapping the monsoon forests without complex classification techniques.
基金Under the auspices of Major State Basic Research Development Program of China (No.2009CB426305)Cultivation Foundation of Science and Technology Innovation Platform of Northeast Normal University (No.106111065202)
文摘Remotely sensing images are now available for monitoring vegetation dynamics over large areas.In this paper,an improved logistic model that combines double logistic model and global function was developed.Using this model with SPOT/NDVI data,three key vegetation phenology metrics,the start of growing season (SOS),the end of growing season (EOS) and the length of growing season (LOS),were extracted and mapped in the Changbai Mountains,and the relationship between the key phenology metrics and elevation were established.Results show that average SOS of forest,cropland and grassland in the Changbai Mountains are on the 119th,145th,and 133rd day of year,respectively.The EOS of forest and grassland are similar,with the average on the 280th and 278th,respectively.In comparison,average EOS of the cropland is relatively earlier.The LOS of forest is mainly from the 160th to 180th,that of the grassland extends from the 140th to the 160th,and that of cropland stretches from the 110th to the 130th.As the latitude increases for the same land cover in the study area,the SOS significantly delays and the EOS becomes earlier.The SOS delays approximately three days as the elevation increases 100 m in the areas with elevation higher than 900 m above sea level (a.s.l.).The EOS is slightly earlier as the elevation increases especially in the areas with elevation below 1200 m a.s.l.The LOS shortens approximately four days as the elevation increases 100 m in the areas with elevation higher than 900 m a.s.l.The relationships between vegetation phenology metrics and elevation may be greatly influenced by the land covers.Validation by comparing with the field data and previous research results indicates that the improved logistic model is reliable and effective for extracting vegetation phenology metrics.
基金supported by the National Natural Science Foundation of China (Nos. 31401476, 31471606)National High-Tech Research and Development Program of China, 863 Program (2014AA093508)Shandong Province Regional Innovation and Development of Marine Economy Demonstration Project
文摘Codfish is a kind of abyssal fish species with a great value in food industry. However, the flavor of codfish, especially the unpleasant odor, has caused serious problems in its processing. To accurately identify the volatile compounds in codfish, a combination of solid phase micro-extraction(SPME) method and simultaneous distillation extraction(SDE) method was used to extract the volatiles. Gas chromatography-mass spectrometry(GC-MS) along with Kovats indices(KI) and authentic standard compounds were used to identify the volatiles. The results showed that a total of 86 volatile compounds were identified in codfish, of them 24 were extracted by SDE, 69 compounds by SPME, and 10 compounds by both SDE and SPME. Seventy volatile compounds were found to have specific odors, of them 7 typical compounds contributed significantly to the flavor of codfish. Alcohols(i.e.,(E)-2-penten-1-ol and 2-octanol), esters(i.e., ethyl butyrate and methyl geranate), aldehydes(i.e., 2-dodecenal and pentadecanal) contributed the most to fresh flavor while nitrogen compounds, sulphur compounds, furans, as well as some ketones(i.e., 2-hydroxy-3-pentanone) brought unpleasant odor, such as fishy and earthy odor. It was indicated that the combination of multiple extraction methods and GC-MS analysis can enhance the accuracy of identification, and provide a reference for the further study on flavor of aquatic products.
基金Supported by the National Natural Science Foundation of China (No. 60672073,60872094)the Program for New Century Excellent Talents in University (NCET-06-0537)the Natural Science Foundation of Ningbo (No. 2007A610037).
文摘A semi-reference image quality assessment metric based on similarity measurement for synthesized virtual viewpoint image (VVI) in free-viewpoint television system (FFV) is proposed in this paper. The key point of the proposed metric is taking resemblant information between VVI and its neighbor view images for quality assessment to make our metric to be extended to multi-semi-reference image quality assessment easily. The proposed metric first extracts impact factors from image features, then combines an image synthesis technique and similarity functions, in which, disparity information are taken into account for registering the resemblant regions. Experiments are divided into three phases. Phase I is to verify the validation of the proposed metric by taking impaired images and original reference into account. The experimental results show the agreement between evaluation scores and bio-characteristic of human visual system. Phase II shows the accordance with Phase I by taking neighbor view as reference. The proposed metric can be taken as a full reference one to evaluate the image quality even though the original reference is absent. Phase III is then performed to evaluate the quality of WI. Evaluation scores in the experimental results are able to evaluate the quality of VVI.
基金Project(11JJ3080)supported by Natural Science Foundation of Hunan Province,ChinaProject(11CY012)supported by Cultivation in Hunan Colleges and Universities,ChinaProject(ET51007)supported by Youth Talent in Hunan University,China
文摘Singular point(SP)extraction is a key component in automatic fingerprint identification system(AFIS).A new method was proposed for fingerprint singular points extraction,based on orientation tensor field and Laurent series.First,fingerprint orientation flow field was obtained,using the gradient of fingerprint image.With these gradients,fingerprint orientation tensor field was calculated.Then,candidate SPs were detected by the cross-correlation energy in multi-scale Gaussian space.The energy was calculated between fingerprint orientation tensor field and Laurent polynomial model.As a global descriptor,the Laurent polynomial coefficients were allowed for rotational invariance.Furthermore,a support vector machine(SVM)classifier was trained to remove spurious SPs,using cross-correlation coefficient as a feature vector.Finally,experiments were performed on Singular Point Detection Competition 2010(SPD2010)database.Compared to the winner algorithm of SPD2010 which has best accuracy of 31.90%,the accuracy of proposed algorithm is 45.34%.The results show that the proposed method outperforms the state-of-the-art detection algorithms by large margin,and the detection is invariant to rotational transformations.
文摘In this work, a hybrid method is proposed to eliminate the limitations of traditional protein-protein interactions (PPIs) extraction methods, such as pattern learning and machine learning. Each sentence from the biomedical literature containing a protein pair describes a PPI which is predicted by first learning syntax patterns typical of PPIs from training corpus and then using their presence as features, along with bag-of-word features in a maximum entropy model. Tested on the BioCreAtIve corpus, the PPIs extraction method, which achieved a precision rate of 64%, recall rate of 60%, improved the performance in terms of F1 value by 11% compared with the component pure pattern- based and bag-of-word methods. The results on this test set were also compared with other three extraction methods and found to improve the performance remarkably.
文摘Urban vegetation has been an important indicator for the evaluation of eco-cities, which is of great significance to promote eeo-city construction. We study and discuss the commonly used urban vegetation extrac-tion methods. The extraction of vegetation points in this study is completed through mathematical statistics, mean-square error, successive differences and iterative algorithm which are based on the analysis of different spatial morphological characteristics in urban point clouds. Linyi, a city of Shandong Province in China, is se-lected as the study area to test this method and the result shows that the proposed method has a strong practicali- ty in urban vegetation point cloud extraction. Only 3D coordinate properties of the LiDAR point clouds are used in this method and it does not require additional information, for instance, return intensity, which makes the method more applicable and operable.