Annual haze in Northern Thailand has become increasingly severe,impacting health and the environment.How-ever,the sources of the haze remain poorly quantified due to limited observational data on aerosol molecular tra...Annual haze in Northern Thailand has become increasingly severe,impacting health and the environment.How-ever,the sources of the haze remain poorly quantified due to limited observational data on aerosol molecular tracers.This study comprehensively investigates chemical composition of PM_(2.5),including both inorganic and organic compounds throughout haze and post-haze periods in 2019 at a rural site of Northern Thailand.Average PM_(2.5) concentrations during haze and post-haze period were 87±36 and 21±11μg/m^(3),respectively.Organic matter was the dominant contributor in PM_(2.5) mass,followed by water soluble inorganic ions and mineral dust.Molecular markers,including levoglucosan,dehydroabietic acid,and 4-nitrocatechol,and ions(Cl^(-),and K^(+)),were used to characterize low haze(PM_(2.5)<100μg/m^(3))and episodic haze(PM_(2.5)>100μg/m^(3)).Low haze is associated with local aerosols from agricultural waste burning,while episodic haze is linked to aged aerosols from mixed agricultural waste,softwood,and hardwood burning.Source apportionment incorporating these molecular markers in receptor modelling(Positive matrix factorization),identified three distinct biomass burning sources:mixed,local,and aged biomass burnings,contributing 31,19 and 13%of PM_(2.5) during haze period.During post-haze period,contributions shifted,with local biomass burning(32%)comparable to secondary sulfate(34%)and mixed dust and traffic sources(26%).These findings demonstrate that both regional and local sources con-tribute to severe haze,highlighting the need for integrated policies for cross-border cooperation as well as stricter regulations to reduce biomass burning in Northern Thailand and Southeast Asia.展开更多
Hexavalent chromium(Cr(Ⅵ)) is an extremely toxic pollutant in aqueous environment.Chemical reduction is the most employed method in decontamination of Cr(Ⅵ).However,the chemical reduction was usually conducted in ac...Hexavalent chromium(Cr(Ⅵ)) is an extremely toxic pollutant in aqueous environment.Chemical reduction is the most employed method in decontamination of Cr(Ⅵ).However,the chemical reduction was usually conducted in acidic media,resulting in considerable waste of acid reagents and the following neutralizing agents.In this study,kinetics and mechanisms of Cr(Ⅵ) reduction by sulfite in alkaline conditions(pH:7-10) were investigated.It reveals that Cr(Ⅵ) reduction follows pseudo-zero-order kinetics,where the rate constants increased markedly with an in situ irradiation of Far-UVC(UV_(222)).Decreasing pH levels slightly favored the reduction.Iodide ion displayed a notable accelerating effect,which not only save the energy input but also minimize the reductant usage.Chloride,sulfate,and carbonate ions exhibit little effect on the reduction,whereas nitrate and nitrite ions,dissolved oxygen as well as Cu(Ⅱ) suppressed the reduction significantly,implying that hydrated electrons produced by UV222 played the most important role in the reaction.Compared to the UV254/sulfite/iodide process,UV222/sulfite/iodide demonstrates clear advantages in the reduction kinetics and the sulfite utilization efficiency,underscoring its potential for effective Cr(Ⅵ) remediation in various environmental settings.展开更多
This paper explores the algebraic essence of universal logic functions(ULFs)from an algebraic perspective.Under the framework of semi-tensor product of matrices,the“sequential nature”of ULFs is revealed.Utilizing th...This paper explores the algebraic essence of universal logic functions(ULFs)from an algebraic perspective.Under the framework of semi-tensor product of matrices,the“sequential nature”of ULFs is revealed.Utilizing the nature,a technique called universal transformation method is proposed,by which any ULF can be transformed into an equivalent expression with desired features that facilitate achieving specific objectives,such as modeling,analyzing and synthesizing universal logical systems.Furthermore,several useful logical operators are constructed in a mixed-dimensional situation,including power-raising operator,power-descending operator,erasure operator,and appending operator.Finally,these results are applied to model and analyze finite state machines and their networks,which demonstrate the practical value of the method and operators.展开更多
Dear Editor,In this letter,we focus on the algebraic relationship between the coefficient matrices and the solution of the stochastic algebraic Riccati equation.It is revealed that,if the coefficient matrices are in a...Dear Editor,In this letter,we focus on the algebraic relationship between the coefficient matrices and the solution of the stochastic algebraic Riccati equation.It is revealed that,if the coefficient matrices are in an algebra,then the solution(and also the control gain in many cases)is also in the same algebra.The main result is verified by a numerical simulation.展开更多
In this paper,we introduce the real pairwise completely positive(RPCP)matrices with one of them is necessarily positive semidefinite while the other one is necessarily entrywise nonnegative,which has a real pairwise c...In this paper,we introduce the real pairwise completely positive(RPCP)matrices with one of them is necessarily positive semidefinite while the other one is necessarily entrywise nonnegative,which has a real pairwise completely positive(RPCP)decomposition.We study the properties of RPCP matrices and give some necessary and sufficient conditions for a matrix pair to be RPCP.First,we give an equivalent decomposition for the RPCP matrices,which is different from the RPCP-decomposition and show that the matrix pair(X,X)is RPCP if and only if X is completely positive.Besides,we also prove that the RPCP matrices checking problem is equivalent to the separable completion problem.A semidefinite algorithm is also proposed for detecting whether or not a matrix pair is RPCP.The asymptotic and finite convergence of the algorithm are also discussed.If it is RPCP,we can further give a RPCP-decomposition for it;if it is not,we can obtain a certificate for this.展开更多
Complete collection of target fluids and effective capture of biomolecules are essential when designing and fabricating sensor electrodes.Assembling a conductive metal-organic framework(MOF)film onto a high-surfaceare...Complete collection of target fluids and effective capture of biomolecules are essential when designing and fabricating sensor electrodes.Assembling a conductive metal-organic framework(MOF)film onto a high-surfacearea porous aerogel to create a three-dimensional(3D)hierarchically ordered structure represented an effective strategy for fabricating sensor electrodes for body fluid detection.In this study,high-precision,confined growth of a self-assembled Cu-HHTP layer on an aerogel assisted by atomic layer deposition was employed to fabricate a hierarchical 3D-ordered metal-organic aerogel(MO A)electrode.This structure comprises two components:a conductive MOF thin film with abundant exposed active sites and a flexible 3D aerogel featuring through-holes with strong adsorption capacity,thereby enhancing liquid confinement and promoting biomolecule adsorption.This approach combines the aerogel's high flexibility and liquid adsorption ability with the conductive network of the CuHHTP film,thereby enabling an effective dopamine(DA)sensor.The sensor based on the 3D-ordered MO A electrode exhibits high sensitivity,with a detection limit of 1.19μM,along with excellent selectivity,stability,reproducibility,and strong anti-interference capability,as evidenced by negligible deviations in DA measurements across aqueous(H_(2)O)and fetal bovine serum(FBS)samples.A proof-of-concept test using human urine produces a pronounced response,confirming the sensor's practical feasibility.展开更多
A simplified analytical approach is proposed for predicting the load-displacement behavior of single piles in unsaturated soils considering the contribution from the nonlinear shear strength and soil stiffness influen...A simplified analytical approach is proposed for predicting the load-displacement behavior of single piles in unsaturated soils considering the contribution from the nonlinear shear strength and soil stiffness influenced by matric suction.This approach includes a Modified Load Transfer Model(MLTM)that can predict the nonlinear relationships between the shear stress and pile-soil relative displacement along the pile shaft,and between the pile base resistance and base settlement.The proposed model is also extended for pile groups to incorporate the interaction effects between individual piles.The analytical approach is validated through a comparative analysis with the measurements from two single pile tests and one pile group test.In addition,a finite element analysis using 3D modeling is carried out to investigate the behavior of pile groups in various unsaturated conditions.This is accomplished with a user-defined subroutine that is written and implemented in ABAQUS to simulate the nonlinear mechanical behavior of unsaturated soils.The predictions derived from the proposed analytical and numerical methods compare well with the measurements of a published experimental study.The proposed methodologies have the potential to be applied in geotechnical engineering practice for the rational design of single piles and pile groups in unsaturated soils.展开更多
Potential games(PG)have attracted the attention of many researchers because of its excellent properties and multi-PG are more flexible and extensible,which greatly improve the application range of PG.Consider that wei...Potential games(PG)have attracted the attention of many researchers because of its excellent properties and multi-PG are more flexible and extensible,which greatly improve the application range of PG.Consider that weights and states to each player are common and practical in many application scenarios,and in this paper,by introducing weight value and state into multi-PG,q-weighted PG and q-state PG are systematically discussed and analyzed to expand the types of PG,respectively.First,using semi-tensor product of matrices(STP),a matrix approach to the modeling of weighted PG is investigated,and the verification method of weighted PG is proposed by defining three matrices,and the problem of how to detect weighted PG can be transformed to solve an algebraic equation,which is composed of the above three matrices.Next,by bringing weight values into multi-PG and detecting the weighted PG for each group,the verification method is extended to the q-weighted PG.Second,the model of state-based PG is constructed,and the problem of how to detect state-based PG can be transformed to solve another algebraic equation,which is seen as an extension of the verification method of weighted PG.Subsequently,the verification of q-state PG is discussed.Finally,we use two examples to demonstrate the validation of obtained results.展开更多
We display sharp bounds for upper and lower spectrum of a Hermitizable tridiagonal matrix.The representations are brought to light by exploiting the characteristic for eigenpairs(eigenvalue and its corresponding eigen...We display sharp bounds for upper and lower spectrum of a Hermitizable tridiagonal matrix.The representations are brought to light by exploiting the characteristic for eigenpairs(eigenvalue and its corresponding eigenvector)of tridiagonal matrices,isospectral transforms and sharp bounds for speed stability of birth-death processes.展开更多
High-performance lithium metal batteries benefit from the construction of composite polymer electrolytes(CPEs)which are synthesized by incorporating inorganic fillers into polymer matrices[1].However,the random distri...High-performance lithium metal batteries benefit from the construction of composite polymer electrolytes(CPEs)which are synthesized by incorporating inorganic fillers into polymer matrices[1].However,the random distribution of added fillers within the polymer matrix can lead to tortuous ion pathways and longer transmission distances(Fig.1).As a result,the ion transport capability of CPEs may decrease,while interface contact may deteriorate.Therefore,the organized arrangement of fillers emerges as a crucial consideration in constructing electrolyte membranes.One highly effective approach is the adoption of a vertically aligned filler configuration,where ceramic fillers are constructed to be perpendicular to the electrolyte membrane.If so,the filler/electrolyte interface impedance can be significantly reduced,while continuous ion transport channels along the specified direction are formed,thus significantly enhancing the ion conduction(Fig.1(a))[1].展开更多
Subcellular location is one of the key biological characteristics of proteins. Position-specific profiles （PSP） have been introduced as important characteristics of proteins in this article. In this study, to obtain...Subcellular location is one of the key biological characteristics of proteins. Position-specific profiles （PSP） have been introduced as important characteristics of proteins in this article. In this study, to obtain position-specific profiles, the Position Specific lterative-Basic Local Alignment Search Tool （PSI-BLAST） has been used to search for protein sequences in a database. Position-specific scoring matrices are extracted from the profiles as one class of characteristics. Four-part amino acid compositions and lst-7th order dipeptide compositions have also been calculated as the other two classes of characteristics. Therefore, twelve characteristic vectors are extracted from each of the protein sequences. Next, the characteristic vectors are weighed by a simple weighing function and inputted into a BP neural network predictor named PSP-Weighted Neural Network （PSP-WNN）. The Levenberg-Marquardt algorithm is employed to adjust the weight matrices and thresholds during the network training instead of the error back propagation algorithm. With a jackknife test on the RH2427 dataset, PSP-WNN has achieved a higher overall prediction accuracy of 88.4% rather than the prediction results by the general BP neural network, Markov model, and fuzzy k-nearest neighbors algorithm on this dataset. In addition, the prediction performance of PSP-WNN has been evaluated with a five-fold cross validation test on the PK7579 dataset and the prediction results have been consistently better than those of the previous method on the basis of several support vector machines, using compositions of both amino acids and amino acid pairs. These results indicate that PSP-WNN is a powerful tool for subcellular localization prediction. At the end of the article, influences on prediction accuracy using different weighting proportions among three characteristic vector categories have been discussed. An appropriate proportion is considered by increasing the prediction accuracy.展开更多
In this paper, we provide some new necessary and sufficient conditions for generalized diagonally dominant matrices and also obtain some criteria for nongeneralized dominant matrices.
On the basis of the paoers[3—7],this paper study the monotonicity problems for the positive semidefinite generalized inverses of the positive semidefinite self-conjugate matrices of quaternions in the Lowner partial ...On the basis of the paoers[3—7],this paper study the monotonicity problems for the positive semidefinite generalized inverses of the positive semidefinite self-conjugate matrices of quaternions in the Lowner partial order,give the explicit formulations of the monotonicity solution sets A{1;≥,T_1;≤B^(1)}and B{1;≥,T_2≥A^(1)}for the(1)-inverse,and two results of the monotonicity charac teriaztion for the(1,2)-inverse.展开更多
An approach for generating test problems by a computer using the Monte Carlo method based upon user-given characterizations is described.A single point X~* is prespocified by the user to be a solution of the test prob...An approach for generating test problems by a computer using the Monte Carlo method based upon user-given characterizations is described.A single point X~* is prespocified by the user to be a solution of the test problems.The approach is flex- ible enough to specify function values,gradients,Hesse,degeneracy degree and ill- conditioned degree at the point X~*.Other numerical features such as indefiniteness, convexity are also under user's control.展开更多
In today's aircraft,the hardware redundancy is driven by the critical surfaces resulting in single point-failures.Reconfiguration technology remoVes the single surface criticality by employing control surfaces wit...In today's aircraft,the hardware redundancy is driven by the critical surfaces resulting in single point-failures.Reconfiguration technology remoVes the single surface criticality by employing control surfaces with aerodynamic redundancy.This paper studies a control reconfiguration scheme based on Control Mixer Concept.A technique for the design of a control mixer for an aircraft with damaged surfaces/actuators using the pseudo-inverse is developed and applied.This paper discusses its applications and limitations based on linear analysis and computer simulation.展开更多
The problem of best approximating, a given square complex matrix in the Frobenius norm by normal matrices under a given spectral restriction is considered. The ne cessary and sufficient condition for the solvability ...The problem of best approximating, a given square complex matrix in the Frobenius norm by normal matrices under a given spectral restriction is considered. The ne cessary and sufficient condition for the solvability of the problem is given. A numerical algorithm for solving the problem is provided and a numerical example is presented.展开更多
文摘Annual haze in Northern Thailand has become increasingly severe,impacting health and the environment.How-ever,the sources of the haze remain poorly quantified due to limited observational data on aerosol molecular tracers.This study comprehensively investigates chemical composition of PM_(2.5),including both inorganic and organic compounds throughout haze and post-haze periods in 2019 at a rural site of Northern Thailand.Average PM_(2.5) concentrations during haze and post-haze period were 87±36 and 21±11μg/m^(3),respectively.Organic matter was the dominant contributor in PM_(2.5) mass,followed by water soluble inorganic ions and mineral dust.Molecular markers,including levoglucosan,dehydroabietic acid,and 4-nitrocatechol,and ions(Cl^(-),and K^(+)),were used to characterize low haze(PM_(2.5)<100μg/m^(3))and episodic haze(PM_(2.5)>100μg/m^(3)).Low haze is associated with local aerosols from agricultural waste burning,while episodic haze is linked to aged aerosols from mixed agricultural waste,softwood,and hardwood burning.Source apportionment incorporating these molecular markers in receptor modelling(Positive matrix factorization),identified three distinct biomass burning sources:mixed,local,and aged biomass burnings,contributing 31,19 and 13%of PM_(2.5) during haze period.During post-haze period,contributions shifted,with local biomass burning(32%)comparable to secondary sulfate(34%)and mixed dust and traffic sources(26%).These findings demonstrate that both regional and local sources con-tribute to severe haze,highlighting the need for integrated policies for cross-border cooperation as well as stricter regulations to reduce biomass burning in Northern Thailand and Southeast Asia.
基金supported by the National Key R&D Program of China(No.2023YFE0112100)the Science and Technology Planning Project of Fujian Province(No.2023Y4015)the Marine and Fishery Devel-opment Special Fund of Xiamen(No.23YYST064QCB36).
文摘Hexavalent chromium(Cr(Ⅵ)) is an extremely toxic pollutant in aqueous environment.Chemical reduction is the most employed method in decontamination of Cr(Ⅵ).However,the chemical reduction was usually conducted in acidic media,resulting in considerable waste of acid reagents and the following neutralizing agents.In this study,kinetics and mechanisms of Cr(Ⅵ) reduction by sulfite in alkaline conditions(pH:7-10) were investigated.It reveals that Cr(Ⅵ) reduction follows pseudo-zero-order kinetics,where the rate constants increased markedly with an in situ irradiation of Far-UVC(UV_(222)).Decreasing pH levels slightly favored the reduction.Iodide ion displayed a notable accelerating effect,which not only save the energy input but also minimize the reductant usage.Chloride,sulfate,and carbonate ions exhibit little effect on the reduction,whereas nitrate and nitrite ions,dissolved oxygen as well as Cu(Ⅱ) suppressed the reduction significantly,implying that hydrated electrons produced by UV222 played the most important role in the reaction.Compared to the UV254/sulfite/iodide process,UV222/sulfite/iodide demonstrates clear advantages in the reduction kinetics and the sulfite utilization efficiency,underscoring its potential for effective Cr(Ⅵ) remediation in various environmental settings.
基金supported in part by the National Natural Science Foundation of China under Grants 62073124 and U1804150.
文摘This paper explores the algebraic essence of universal logic functions(ULFs)from an algebraic perspective.Under the framework of semi-tensor product of matrices,the“sequential nature”of ULFs is revealed.Utilizing the nature,a technique called universal transformation method is proposed,by which any ULF can be transformed into an equivalent expression with desired features that facilitate achieving specific objectives,such as modeling,analyzing and synthesizing universal logical systems.Furthermore,several useful logical operators are constructed in a mixed-dimensional situation,including power-raising operator,power-descending operator,erasure operator,and appending operator.Finally,these results are applied to model and analyze finite state machines and their networks,which demonstrate the practical value of the method and operators.
文摘Dear Editor,In this letter,we focus on the algebraic relationship between the coefficient matrices and the solution of the stochastic algebraic Riccati equation.It is revealed that,if the coefficient matrices are in an algebra,then the solution(and also the control gain in many cases)is also in the same algebra.The main result is verified by a numerical simulation.
文摘In this paper,we introduce the real pairwise completely positive(RPCP)matrices with one of them is necessarily positive semidefinite while the other one is necessarily entrywise nonnegative,which has a real pairwise completely positive(RPCP)decomposition.We study the properties of RPCP matrices and give some necessary and sufficient conditions for a matrix pair to be RPCP.First,we give an equivalent decomposition for the RPCP matrices,which is different from the RPCP-decomposition and show that the matrix pair(X,X)is RPCP if and only if X is completely positive.Besides,we also prove that the RPCP matrices checking problem is equivalent to the separable completion problem.A semidefinite algorithm is also proposed for detecting whether or not a matrix pair is RPCP.The asymptotic and finite convergence of the algorithm are also discussed.If it is RPCP,we can further give a RPCP-decomposition for it;if it is not,we can obtain a certificate for this.
基金financially supported by the National Natural Science Foundation of China(No.52203328)the Fundamental Research Funds for the Central Universities(Nos.2232024D-33 and 2232023A-10)+1 种基金the State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,Major program(No.23M1060280)Shanghai Pujiang Program(No.23PJ1400600)
文摘Complete collection of target fluids and effective capture of biomolecules are essential when designing and fabricating sensor electrodes.Assembling a conductive metal-organic framework(MOF)film onto a high-surfacearea porous aerogel to create a three-dimensional(3D)hierarchically ordered structure represented an effective strategy for fabricating sensor electrodes for body fluid detection.In this study,high-precision,confined growth of a self-assembled Cu-HHTP layer on an aerogel assisted by atomic layer deposition was employed to fabricate a hierarchical 3D-ordered metal-organic aerogel(MO A)electrode.This structure comprises two components:a conductive MOF thin film with abundant exposed active sites and a flexible 3D aerogel featuring through-holes with strong adsorption capacity,thereby enhancing liquid confinement and promoting biomolecule adsorption.This approach combines the aerogel's high flexibility and liquid adsorption ability with the conductive network of the CuHHTP film,thereby enabling an effective dopamine(DA)sensor.The sensor based on the 3D-ordered MO A electrode exhibits high sensitivity,with a detection limit of 1.19μM,along with excellent selectivity,stability,reproducibility,and strong anti-interference capability,as evidenced by negligible deviations in DA measurements across aqueous(H_(2)O)and fetal bovine serum(FBS)samples.A proof-of-concept test using human urine produces a pronounced response,confirming the sensor's practical feasibility.
基金financially supported by NSERC,CanadaDiscovery Grant 2020(Grant No.5808).
文摘A simplified analytical approach is proposed for predicting the load-displacement behavior of single piles in unsaturated soils considering the contribution from the nonlinear shear strength and soil stiffness influenced by matric suction.This approach includes a Modified Load Transfer Model(MLTM)that can predict the nonlinear relationships between the shear stress and pile-soil relative displacement along the pile shaft,and between the pile base resistance and base settlement.The proposed model is also extended for pile groups to incorporate the interaction effects between individual piles.The analytical approach is validated through a comparative analysis with the measurements from two single pile tests and one pile group test.In addition,a finite element analysis using 3D modeling is carried out to investigate the behavior of pile groups in various unsaturated conditions.This is accomplished with a user-defined subroutine that is written and implemented in ABAQUS to simulate the nonlinear mechanical behavior of unsaturated soils.The predictions derived from the proposed analytical and numerical methods compare well with the measurements of a published experimental study.The proposed methodologies have the potential to be applied in geotechnical engineering practice for the rational design of single piles and pile groups in unsaturated soils.
基金supported by the National Natural Science Foundation of China Grant No.62203328.
文摘Potential games(PG)have attracted the attention of many researchers because of its excellent properties and multi-PG are more flexible and extensible,which greatly improve the application range of PG.Consider that weights and states to each player are common and practical in many application scenarios,and in this paper,by introducing weight value and state into multi-PG,q-weighted PG and q-state PG are systematically discussed and analyzed to expand the types of PG,respectively.First,using semi-tensor product of matrices(STP),a matrix approach to the modeling of weighted PG is investigated,and the verification method of weighted PG is proposed by defining three matrices,and the problem of how to detect weighted PG can be transformed to solve an algebraic equation,which is composed of the above three matrices.Next,by bringing weight values into multi-PG and detecting the weighted PG for each group,the verification method is extended to the q-weighted PG.Second,the model of state-based PG is constructed,and the problem of how to detect state-based PG can be transformed to solve another algebraic equation,which is seen as an extension of the verification method of weighted PG.Subsequently,the verification of q-state PG is discussed.Finally,we use two examples to demonstrate the validation of obtained results.
基金Supported by the National Natural Science Foundation of China(Grant Nos.11771046,12101186)Beijing Natural Science Foundation(Grant No.1254039).
文摘We display sharp bounds for upper and lower spectrum of a Hermitizable tridiagonal matrix.The representations are brought to light by exploiting the characteristic for eigenpairs(eigenvalue and its corresponding eigenvector)of tridiagonal matrices,isospectral transforms and sharp bounds for speed stability of birth-death processes.
基金supported by the National Natural Science Foundation of China(No.51972293)Hangzhou Key Research Program Project(2023SZD0099)LingYan Project(2024C01090).
文摘High-performance lithium metal batteries benefit from the construction of composite polymer electrolytes(CPEs)which are synthesized by incorporating inorganic fillers into polymer matrices[1].However,the random distribution of added fillers within the polymer matrix can lead to tortuous ion pathways and longer transmission distances(Fig.1).As a result,the ion transport capability of CPEs may decrease,while interface contact may deteriorate.Therefore,the organized arrangement of fillers emerges as a crucial consideration in constructing electrolyte membranes.One highly effective approach is the adoption of a vertically aligned filler configuration,where ceramic fillers are constructed to be perpendicular to the electrolyte membrane.If so,the filler/electrolyte interface impedance can be significantly reduced,while continuous ion transport channels along the specified direction are formed,thus significantly enhancing the ion conduction(Fig.1(a))[1].
基金the National Natural Science Foundation of China (No. 60471003).
文摘Subcellular location is one of the key biological characteristics of proteins. Position-specific profiles （PSP） have been introduced as important characteristics of proteins in this article. In this study, to obtain position-specific profiles, the Position Specific lterative-Basic Local Alignment Search Tool （PSI-BLAST） has been used to search for protein sequences in a database. Position-specific scoring matrices are extracted from the profiles as one class of characteristics. Four-part amino acid compositions and lst-7th order dipeptide compositions have also been calculated as the other two classes of characteristics. Therefore, twelve characteristic vectors are extracted from each of the protein sequences. Next, the characteristic vectors are weighed by a simple weighing function and inputted into a BP neural network predictor named PSP-Weighted Neural Network （PSP-WNN）. The Levenberg-Marquardt algorithm is employed to adjust the weight matrices and thresholds during the network training instead of the error back propagation algorithm. With a jackknife test on the RH2427 dataset, PSP-WNN has achieved a higher overall prediction accuracy of 88.4% rather than the prediction results by the general BP neural network, Markov model, and fuzzy k-nearest neighbors algorithm on this dataset. In addition, the prediction performance of PSP-WNN has been evaluated with a five-fold cross validation test on the PK7579 dataset and the prediction results have been consistently better than those of the previous method on the basis of several support vector machines, using compositions of both amino acids and amino acid pairs. These results indicate that PSP-WNN is a powerful tool for subcellular localization prediction. At the end of the article, influences on prediction accuracy using different weighting proportions among three characteristic vector categories have been discussed. An appropriate proportion is considered by increasing the prediction accuracy.
文摘In this paper, we provide some new necessary and sufficient conditions for generalized diagonally dominant matrices and also obtain some criteria for nongeneralized dominant matrices.
文摘On the basis of the paoers[3—7],this paper study the monotonicity problems for the positive semidefinite generalized inverses of the positive semidefinite self-conjugate matrices of quaternions in the Lowner partial order,give the explicit formulations of the monotonicity solution sets A{1;≥,T_1;≤B^(1)}and B{1;≥,T_2≥A^(1)}for the(1)-inverse,and two results of the monotonicity charac teriaztion for the(1,2)-inverse.
文摘An approach for generating test problems by a computer using the Monte Carlo method based upon user-given characterizations is described.A single point X~* is prespocified by the user to be a solution of the test problems.The approach is flex- ible enough to specify function values,gradients,Hesse,degeneracy degree and ill- conditioned degree at the point X~*.Other numerical features such as indefiniteness, convexity are also under user's control.
文摘In today's aircraft,the hardware redundancy is driven by the critical surfaces resulting in single point-failures.Reconfiguration technology remoVes the single surface criticality by employing control surfaces with aerodynamic redundancy.This paper studies a control reconfiguration scheme based on Control Mixer Concept.A technique for the design of a control mixer for an aircraft with damaged surfaces/actuators using the pseudo-inverse is developed and applied.This paper discusses its applications and limitations based on linear analysis and computer simulation.
文摘The problem of best approximating, a given square complex matrix in the Frobenius norm by normal matrices under a given spectral restriction is considered. The ne cessary and sufficient condition for the solvability of the problem is given. A numerical algorithm for solving the problem is provided and a numerical example is presented.
