Based on S-rough sets（singular rough sets）, this paper presents function S-rough sets （function singular rough sets）and its mathematical structures and features. Function S-rough sets has two forms： function one ...Based on S-rough sets（singular rough sets）, this paper presents function S-rough sets （function singular rough sets）and its mathematical structures and features. Function S-rough sets has two forms： function one direction S-rough sets （function one direction singular rough sets） and function two direction S-rough sets （function two direction singular rough sets）. This paper advances the relationship theorem of function S-rough sets and S-rough sets. Function S-rough sets is the general form of S-rough sets, and S-rough sets is the special ease of function S-rough sets. In this paper, applications of function S-rough sets in rough law mining-discovery of system are given. Function S-rough sets is a new research direction of rough sets and rough system.展开更多
Function S-rough sets （function singular rough sets） is defined on a -function equivalence class [u]. Function S-rough sets is the extension form of S-rough sets. By using the function S-rough sets, this paper gives...Function S-rough sets （function singular rough sets） is defined on a -function equivalence class [u]. Function S-rough sets is the extension form of S-rough sets. By using the function S-rough sets, this paper gives rough law generation model of a-function equivalence class, discussion on law mining and law discovery in systems, and application of law mining and law discovery in communication system. Function S-rough sets is a new theory and method in law mining research.展开更多
In this paper, we give some characteristic properties of star-shaped sets which include a subset of a convex metric space. Using the characteristic properties, we discuss the existence problems of fixed points of none...In this paper, we give some characteristic properties of star-shaped sets which include a subset of a convex metric space. Using the characteristic properties, we discuss the existence problems of fixed points of nonexpansive type mappings on star-shaped subsets of convex metric spaces, which generalize the recent results obtained by Ding Xie-ping, Beg and Azam. Finally, we give an example which shows that our generalizations are essential.展开更多
A novel contour tracking method using weighted structure tensor based variational level set is proposed in this paper.The image is first converted to weighted structure tensor field by extracting apositive definite sy...A novel contour tracking method using weighted structure tensor based variational level set is proposed in this paper.The image is first converted to weighted structure tensor field by extracting apositive definite symmetric covariance matrix for each pixel.Then,a level set method is employed to represent object contour implicitly which separates the image domain into two areas each modeled by tensor field based Gaussian mixture model separately.By solving agradient flow equation of energy functional with respect to the level set,the object contour will converge to its real profile in the newly arrived frame.Experimental results on several video sequences demonstrate the better performance of our method than the other two contour tracking algorithms.展开更多
A large gas reservoir in the Sinian Dengying Fm was recently discovered in Anyue area,central Sichuan Basin.In order to promote the oil and gas exploration in this area,it is of great significance to sustainably deepe...A large gas reservoir in the Sinian Dengying Fm was recently discovered in Anyue area,central Sichuan Basin.In order to promote the oil and gas exploration in this area,it is of great significance to sustainably deepen the analysis on its high-quality reservoir distribution and sourcereservoir assemblage.In this paper,a series of studies were performed on the sequence frameworks and sedimentary filling evolution characteristics of the Dengying Fm in centralewestern Sichuan Basin,and their controlling effects on the reservoir development and distribution and source-reservoir assemblage during its sedimentation.It is shown that the Deyang-Anyue paleo-rift is,on the whole,distributed in a NW direction,and is morphologically wide and steep in the north,but narrow and gentle in the south.There are two rift boundaries of the second and fourth members of Dengying Fm(Deng 2 Member and Deng 4 Member,respectively).The rift of Deng 2 Member is distributed in the shape of“U”in Deyang-Neijiang area.Dengying Fm is divided into four third-order sequences(SQ1-SQ4).In SQ3 of Gaoshiti-Moxi area,central Sichuan Basin,a complete sedimentation reflection structure of transgressive overlap and regressive progradation can be identified with earlyemiddle Deng 4 Member platform margin.The paleo-rift was in embryo before the sedimentation of Sinian,so the sedimentary filling and lithofacies distribution of the Sinian were influenced by the inherited activities of pre-Sinian rifts.The favorable distribution zones of highquality reservoirs are located at the rift margins of Deng 2 and Deng 4 Members that were formed respectively during the SQ2 and SQ4 and the platform margin of early Deng 4 Member that was formed during the SQ3.A laterally connected source-reservoir assemblage occurs at the margins of Deng 2 and Deng 4 Members around the Lower Cambrian source rocks of the paleo-rift.The northwestward extending margin zone along the eastern flank of the paleo-rift shows a good potential for hydrocarbon accumulation.展开更多
The rapid prediction of seepage mass flow in soil is essential for understanding fluid transport in porous media.This study proposes a new method for fast prediction of soil seepage mass flow by combining mesoscopic m...The rapid prediction of seepage mass flow in soil is essential for understanding fluid transport in porous media.This study proposes a new method for fast prediction of soil seepage mass flow by combining mesoscopic modeling with deep learning.Porous media structures were generated using the Quartet Structure Generation Set(QSGS)method,and a mesoscopic-scale seepage calculation model was applied to compute flow rates.These results were then used to train a deep learning model for rapid prediction.The analysis shows that larger average pore diameters lead to higher internal flow velocities and mass flow rates,while pressure drops significantly at the throats of fine pores.The trained model predicts seepage mass flow rates with deviations within±20%,achieving a root mean square error of 0.24261 and an average deviation of-0.02197.Importantly,the method performs well even with limited training data,though image-based deep learning approaches may yield better accuracy when larger datasets are available.展开更多
This paper deals with the FEEDBACK VERTEX SET problem on undirected graphs, which asks for the existence of a vertex set of bounded size that intersects all cycles. Due it is theoretical and practical importance,the p...This paper deals with the FEEDBACK VERTEX SET problem on undirected graphs, which asks for the existence of a vertex set of bounded size that intersects all cycles. Due it is theoretical and practical importance,the problem has been the subject of intensive study. Motivated by the parameter ecology program we attempt to classify the parameterized and kernelization complexity of FEEDBACK VERTEX SET for a wide range of parameters.We survey known results and present several new complexity classifications. For example, we prove that FEEDBACK VERTEX SET is fixed-parameter tractable parameterized by the vertex-deletion distance to a chordal graph. We also prove that the problem admits a polynomial kernel when parameterized by the vertex-deletion distance to a pseudo forest, a graph in which every connected component has at most one cycle. In contrast, we prove that a slightly smaller parameterization does not allow for a polynomial kernel unless NP coNP=poly and the polynomial-time hierarchy collapses.展开更多
基金This project was surpported by the Natural Science Foundation of Shandong Province of China (Y2004A94)
文摘Based on S-rough sets（singular rough sets）, this paper presents function S-rough sets （function singular rough sets）and its mathematical structures and features. Function S-rough sets has two forms： function one direction S-rough sets （function one direction singular rough sets） and function two direction S-rough sets （function two direction singular rough sets）. This paper advances the relationship theorem of function S-rough sets and S-rough sets. Function S-rough sets is the general form of S-rough sets, and S-rough sets is the special ease of function S-rough sets. In this paper, applications of function S-rough sets in rough law mining-discovery of system are given. Function S-rough sets is a new research direction of rough sets and rough system.
基金This project was supported by Natural Science Foundation of Shandong Province of China (Y2004A04), Natural ScienceFoundation of Fujian of China (Z051049) and Education Foundation of Fujian of China (JA04268),.
文摘Function S-rough sets （function singular rough sets） is defined on a -function equivalence class [u]. Function S-rough sets is the extension form of S-rough sets. By using the function S-rough sets, this paper gives rough law generation model of a-function equivalence class, discussion on law mining and law discovery in systems, and application of law mining and law discovery in communication system. Function S-rough sets is a new theory and method in law mining research.
文摘In this paper, we give some characteristic properties of star-shaped sets which include a subset of a convex metric space. Using the characteristic properties, we discuss the existence problems of fixed points of nonexpansive type mappings on star-shaped subsets of convex metric spaces, which generalize the recent results obtained by Ding Xie-ping, Beg and Azam. Finally, we give an example which shows that our generalizations are essential.
基金Supported by the National High-Tech Research & Development Program of China(2009AA01Z323)
文摘A novel contour tracking method using weighted structure tensor based variational level set is proposed in this paper.The image is first converted to weighted structure tensor field by extracting apositive definite symmetric covariance matrix for each pixel.Then,a level set method is employed to represent object contour implicitly which separates the image domain into two areas each modeled by tensor field based Gaussian mixture model separately.By solving agradient flow equation of energy functional with respect to the level set,the object contour will converge to its real profile in the newly arrived frame.Experimental results on several video sequences demonstrate the better performance of our method than the other two contour tracking algorithms.
文摘A large gas reservoir in the Sinian Dengying Fm was recently discovered in Anyue area,central Sichuan Basin.In order to promote the oil and gas exploration in this area,it is of great significance to sustainably deepen the analysis on its high-quality reservoir distribution and sourcereservoir assemblage.In this paper,a series of studies were performed on the sequence frameworks and sedimentary filling evolution characteristics of the Dengying Fm in centralewestern Sichuan Basin,and their controlling effects on the reservoir development and distribution and source-reservoir assemblage during its sedimentation.It is shown that the Deyang-Anyue paleo-rift is,on the whole,distributed in a NW direction,and is morphologically wide and steep in the north,but narrow and gentle in the south.There are two rift boundaries of the second and fourth members of Dengying Fm(Deng 2 Member and Deng 4 Member,respectively).The rift of Deng 2 Member is distributed in the shape of“U”in Deyang-Neijiang area.Dengying Fm is divided into four third-order sequences(SQ1-SQ4).In SQ3 of Gaoshiti-Moxi area,central Sichuan Basin,a complete sedimentation reflection structure of transgressive overlap and regressive progradation can be identified with earlyemiddle Deng 4 Member platform margin.The paleo-rift was in embryo before the sedimentation of Sinian,so the sedimentary filling and lithofacies distribution of the Sinian were influenced by the inherited activities of pre-Sinian rifts.The favorable distribution zones of highquality reservoirs are located at the rift margins of Deng 2 and Deng 4 Members that were formed respectively during the SQ2 and SQ4 and the platform margin of early Deng 4 Member that was formed during the SQ3.A laterally connected source-reservoir assemblage occurs at the margins of Deng 2 and Deng 4 Members around the Lower Cambrian source rocks of the paleo-rift.The northwestward extending margin zone along the eastern flank of the paleo-rift shows a good potential for hydrocarbon accumulation.
基金Dynamics of CO_(2) Leakage and Seepage in Wellbores Under Reservoir Stimulation,grant number YJCCUS25SFW0004.
文摘The rapid prediction of seepage mass flow in soil is essential for understanding fluid transport in porous media.This study proposes a new method for fast prediction of soil seepage mass flow by combining mesoscopic modeling with deep learning.Porous media structures were generated using the Quartet Structure Generation Set(QSGS)method,and a mesoscopic-scale seepage calculation model was applied to compute flow rates.These results were then used to train a deep learning model for rapid prediction.The analysis shows that larger average pore diameters lead to higher internal flow velocities and mass flow rates,while pressure drops significantly at the throats of fine pores.The trained model predicts seepage mass flow rates with deviations within±20%,achieving a root mean square error of 0.24261 and an average deviation of-0.02197.Importantly,the method performs well even with limited training data,though image-based deep learning approaches may yield better accuracy when larger datasets are available.
基金supported by the European Research Council through Starting Grant 306992 "Parameterized Approximation"
文摘This paper deals with the FEEDBACK VERTEX SET problem on undirected graphs, which asks for the existence of a vertex set of bounded size that intersects all cycles. Due it is theoretical and practical importance,the problem has been the subject of intensive study. Motivated by the parameter ecology program we attempt to classify the parameterized and kernelization complexity of FEEDBACK VERTEX SET for a wide range of parameters.We survey known results and present several new complexity classifications. For example, we prove that FEEDBACK VERTEX SET is fixed-parameter tractable parameterized by the vertex-deletion distance to a chordal graph. We also prove that the problem admits a polynomial kernel when parameterized by the vertex-deletion distance to a pseudo forest, a graph in which every connected component has at most one cycle. In contrast, we prove that a slightly smaller parameterization does not allow for a polynomial kernel unless NP coNP=poly and the polynomial-time hierarchy collapses.
