This paper discusses methods for character extraction on the basis of statistical and structural features of gray_level images,and proposes a dynamic local contrast threshold method accommodating to line width.Precise...This paper discusses methods for character extraction on the basis of statistical and structural features of gray_level images,and proposes a dynamic local contrast threshold method accommodating to line width.Precise locating of character string is realized by exploiting horizontal projection and character arrangements of binary images in horizontal and vertical directions respectively.Also discussed is the method for segmentation of characters in binary images,which is based on projection taking stroke width and character sizes into account.A new method for character identification is explored,which is based on compound neural networks.A complex neural network consists of two sub_nets,the first sub_net performs self_association of patterns via 2_dimentional local_connected 3_order networks,the second sub_net,linking with a locally connected BP networks,performs classification.The reliability of the network recognition is reinforced by introducing conditions for identification denial.Experiments confirm that the proposed methods possess the advantages of impressive robustness,rapid processing and high accuracy of identification.展开更多
The metal-organic frameworks(MOFs)have the characteristics of high porosity and crystallinity,which also makes MOFs have the advantages of high sensitivity,high selectivity and high efficiency in the field of fluoresc...The metal-organic frameworks(MOFs)have the characteristics of high porosity and crystallinity,which also makes MOFs have the advantages of high sensitivity,high selectivity and high efficiency in the field of fluorescence sensing.It can detect the target substance efficiently and quickly,and has excellent anti-interference.Therefore,MOFs materials are also considered as ideal materials for fluorescence sensors.This paper introduces three common preparation methods of MOFs materials:hydrothermal/solvothermal method,mechanochemical method and microwave method.We focus on the application status of MOFs materials in the three fluorescence sensing fields of small molecules,metal cations and inorganic anions,as well as the shortcomings and improvement methods of MOFs materials in this application field.Finally,in view of the shortcomings of MOFs materials in the field of fluorescence sensing,such as poor stability,fluorescence quenching phenomenon susceptible to environmental interference,etc.,it is proposed that more in-depth research should be carried out in the future in terms of anti-interference and reuse of MOFs materials.展开更多
文摘This paper discusses methods for character extraction on the basis of statistical and structural features of gray_level images,and proposes a dynamic local contrast threshold method accommodating to line width.Precise locating of character string is realized by exploiting horizontal projection and character arrangements of binary images in horizontal and vertical directions respectively.Also discussed is the method for segmentation of characters in binary images,which is based on projection taking stroke width and character sizes into account.A new method for character identification is explored,which is based on compound neural networks.A complex neural network consists of two sub_nets,the first sub_net performs self_association of patterns via 2_dimentional local_connected 3_order networks,the second sub_net,linking with a locally connected BP networks,performs classification.The reliability of the network recognition is reinforced by introducing conditions for identification denial.Experiments confirm that the proposed methods possess the advantages of impressive robustness,rapid processing and high accuracy of identification.
基金supported by the Natural Science Research Project of Anhui Educational Committee(13220346)Scientific Research Foundation for High-level Talents of Anhui University of Science and Technology(1321056)
文摘The metal-organic frameworks(MOFs)have the characteristics of high porosity and crystallinity,which also makes MOFs have the advantages of high sensitivity,high selectivity and high efficiency in the field of fluorescence sensing.It can detect the target substance efficiently and quickly,and has excellent anti-interference.Therefore,MOFs materials are also considered as ideal materials for fluorescence sensors.This paper introduces three common preparation methods of MOFs materials:hydrothermal/solvothermal method,mechanochemical method and microwave method.We focus on the application status of MOFs materials in the three fluorescence sensing fields of small molecules,metal cations and inorganic anions,as well as the shortcomings and improvement methods of MOFs materials in this application field.Finally,in view of the shortcomings of MOFs materials in the field of fluorescence sensing,such as poor stability,fluorescence quenching phenomenon susceptible to environmental interference,etc.,it is proposed that more in-depth research should be carried out in the future in terms of anti-interference and reuse of MOFs materials.
