This paper suggests that a single class rather than methods should be used as the slice scope to compute class cohesion. First, for a given attribute, the statements in all methods that last define the attribute are c...This paper suggests that a single class rather than methods should be used as the slice scope to compute class cohesion. First, for a given attribute, the statements in all methods that last define the attribute are computed. Then, the forward and backward data slices for this attribute are generated by using the class as the slice scope and are combined to compute the corresponding class data slice. Finally, the class cohesion is computed based on all class data slices for the attributes. Compared to traditional cohesion metrics that use methods as the slice scope, the proposed metrics that use a single class as slice scope take into account the possible interactions between the methods. The experimental results show that class cohesion can be more accurately measured when using the class as the slice scope.展开更多
The migration,accumulation,and high yield of hydrocarbons in tight sandstone reservoirs are closely tied to the natural fracture systems within the reservoirs.Large-scale fracture networks not only enhance reservoir s...The migration,accumulation,and high yield of hydrocarbons in tight sandstone reservoirs are closely tied to the natural fracture systems within the reservoirs.Large-scale fracture networks not only enhance reservoir seepage capacity but also influence effective productivity and subsequent fracturing reconstruction.Given the diverse mechanical behaviors,such as migration,penetration,or fracture arrest,traditional assumptions about fracture interaction criteria fail to address this complexity.To resolve these issues,a global cohesive element method is proposed to model random natural fractures.This approach verifies intersection models based on real-time stress conditions rather than pre-set criteria,enabling better characterization of interactions between hydraulic and natural fractures.Research has shown that the elastic modulus,horizontal stress difference,and fracturing fluid pumping rate significantly promote the expansion of hydraulic fractures.The use of low viscosity fracturing fluid can observe a decrease in the width of fractures near the wellbore,which may cause fractures to deflect when interacting with natural fractures.However,simulations under these conditions did not form a“complex network of fractures”.It is worth noting that when the local stress difference is zero,the result is close to the formation of this network.Excessive spacing will reduce the interaction between fractures,resulting in a decrease in the total length of fractures.By comprehensively analyzing these factors,an optimal combination can be identified,increasing the likelihood of achieving a“complex fracture network”.This paper thoroughly investigates hydraulic fracture propagation in naturally fractured reservoirs under various conditions,offering insights for developing efficient fracturing methods.展开更多
Slope failures,particularly in railway embankments during intense rainfall,are a major cause of economic damage and humanitarian loss.To forecast how shear cracks develop in slopes under heavy precipitation,we present...Slope failures,particularly in railway embankments during intense rainfall,are a major cause of economic damage and humanitarian loss.To forecast how shear cracks develop in slopes under heavy precipitation,we present a novel modeling framework:the Extended Cohesive Damage Element enhanced by soil moisture(SMECDE).The method first translates forecasted rainfall into soil moisture levels via an established correspondence.Then,recognizing that rainfall infiltration lowers soil cohesion—particularly at varying depths—we introduce a Soil Moisture Decoherence Model(SMDM)based on experimental data,which quantifies how cohesion degrades with moisture and how depth affects this process.By embedding SMDM within the ECDE technique,we investigate how shear fractures propagate under different moisture conditions throughout the slope profile.We apply SMECDE to a real railway embankment case to identify critical moisture thresholds and crack growth patterns.Validation is performed by comparing predictions against field measurements and weather station records,and further checked through simulations of large-scale plastic deformation in ABAQUS.展开更多
The goal of this paper is to investigate the theory of Noether solvability for Volterra singular integral equations(VSIEs)with convolution and Cauchy kernels in a more general function class.To obtain the analytic sol...The goal of this paper is to investigate the theory of Noether solvability for Volterra singular integral equations(VSIEs)with convolution and Cauchy kernels in a more general function class.To obtain the analytic solutions,we transform such equations into boundary value problems with discontinuous coefficients by the properties of Fourier analysis.In view of the analytical Riemann-Hilbert method,the generalized Liouville theorem and Sokhotski-Plemelj formula,we get the uniqueness and existence of solutions for such problems,and study the asymptotic property of solutions at nodes.Therefore,this paper improves the theory of singular integral equations and boundary value problems.展开更多
As the key technology of extracting remote sensing information,the classification of remote sensing images has always been the research focus in the field of remote sensing. The paper introduces the classification pro...As the key technology of extracting remote sensing information,the classification of remote sensing images has always been the research focus in the field of remote sensing. The paper introduces the classification process and system of remote sensing images. According to the recent research status of domestic and international remote sensing classification methods,the new study dynamics of remote sensing classification,such as artificial neural networks,support vector machine,active learning and ensemble multi-classifiers,were introduced,providing references for the automatic and intelligent development of remote sensing images classification.展开更多
Grain-size class-Std(GSCStd) and Grain-size class-dD(GSCdD) methods are simple statistical approaches for classifying bulk grain-size distributions(GSDs) into grain-size fractions. Although these two methods were deve...Grain-size class-Std(GSCStd) and Grain-size class-dD(GSCdD) methods are simple statistical approaches for classifying bulk grain-size distributions(GSDs) into grain-size fractions. Although these two methods were developed based on similar statistical principles, the classification difference between these two methods has not been analyzed. In this study, GSCStd and GSCdD methods are conducted in thirteen grain-size data sequences to examine the applicability for identifying grain size fractions. Results show that, application of the GSCStd method is equivalent to that of the GSCdD method in identifying finer grain-size fractions, and the difference between the two methods mainly comes from the identification of coarse grain-size fractions. Thus, finer grain-size fractions are recommended for use in research of surface aeolian and paleo-aeolian sediments. In addition, our results do not completely agree with previous studies, coarser grain-size fractions in our case suggest that the GSCdD method may not be more applicable than the GSCStd method.展开更多
With the development of social civilization, people's spiritual pursuit is constantly changing and more and more attention is paid to education reform. It is very important to innovate the way of education and tea...With the development of social civilization, people's spiritual pursuit is constantly changing and more and more attention is paid to education reform. It is very important to innovate the way of education and teaching, to perfect the system of education and teaching and to dig the inner potential of students deeply, so as to cultivate a large number of high-quality talents, which is conducive to the new success of the modernization of society. During the period of secondary vocational education, it is the duty of the head teacher to continuously strengthen class management, care about students' study and life, and further enhance students' sense of ownership. This article specially from several aspects, on the teacher in charge of secondary vocational management of the class methods and skills were summarized and analyzed.展开更多
In this note,the explicit form of the N soliton solutions for a class of the system of LS nonlinear wave interaction have been obtained by using Hirota's method.
The acoustic vibration signal of tank is disassembled into the sum of intrinsic mode function （IMF） by multi-resolution empirical mode decomposition （EMD） method. The instantaneous frequency is obtained, and featu...The acoustic vibration signal of tank is disassembled into the sum of intrinsic mode function （IMF） by multi-resolution empirical mode decomposition （EMD） method. The instantaneous frequency is obtained, and feature transformation matrix is figured out by class scatter matrix. Multi- dimensional scale energy vector is mapped into low-dimensional eigenvector, and classification extraction is realized. This method sufficiently separates of different sound target features. The test result indicates that it is effective.展开更多
The interaction between the classes or within the classes shows the complexity of the design. For one smaller problem, there may be more than one software design but who will be the best;depends on the complexity leve...The interaction between the classes or within the classes shows the complexity of the design. For one smaller problem, there may be more than one software design but who will be the best;depends on the complexity level of software design. Therefore, coupling and cohesion which shows the interlinking of classes and strength of classes;control the complexity of the design. The best software object oriented design is based upon the low coupling and high cohesion level. In the present work, a real case study of Life Insurance policy for handicapped person is demonstrated through the UML Class Diagram;coupling and cohesion levels are measured and results are demonstrated in the form of tables.展开更多
Music situational teaching method aims to mobilize the students’thoughts in a natural state so as to enhance the attractiveness and efficiency of music classes.In the process of this method,some specific situational ...Music situational teaching method aims to mobilize the students’thoughts in a natural state so as to enhance the attractiveness and efficiency of music classes.In the process of this method,some specific situational are designed according to the characteristics of music and under the guidance of psychology,methodology,pedagogy and other theories,and various sensory organs are employed.Different from traditional teaching method,situational teaching method creates learning situational for students,which is consistent with the characteristics of primary school students’physical and mental development and maximizes students’experience and feeling of music.展开更多
In this study,an alternative modelling approach for absorbed hydrogen stress corrosion cracking(SCC)is proposed,with hydrogen-enhanced decohesion(HEDE)identified as the key failure mechanism.All analyses have been per...In this study,an alternative modelling approach for absorbed hydrogen stress corrosion cracking(SCC)is proposed,with hydrogen-enhanced decohesion(HEDE)identified as the key failure mechanism.All analyses have been performed by utilising only ABAQUS standard elements,COH2D4T and CPE4T,already available within the software and without the need to develop external subroutines.The study also tends to highlight the criticality of implementing a correct Traction Separation Law(TSL)curve to simulate the hydrogen diffusion within the specimen and using the concept of dynamic hydrogen penetration by continuously updating the hydrogen concentration boundary conditions as the crack propagates.In conclusion,this study successfully demonstrated that standard software elements(COH2D4T and CPE4T)can effectively model physical problems and crack velocity propagation without custom subroutines.It emphasized that while the specific shape of the Traction-Separation Law(TSL)is less critical,its correct implementation is vital for simulating dynamic hydrogen coverage.Crucially,excluding this dynamic coverage—a common practice—risks significantly underestimating crack propagation speed.Although results incorporating dynamic coverage aligned well with experimental data,minor discrepancies are likely due to unmodeled factors like material property variations,hydrogen trapping,temperature,and granular microstructure,which are proposed for future research.展开更多
The particles of different shapes,multi-walled carbon nanotubes(CNTs)and graphene nanosheets(GNs),were used to modulate the mechanical properties and anisotropy of the magnets.It is found that the rodshaped CNTs can i...The particles of different shapes,multi-walled carbon nanotubes(CNTs)and graphene nanosheets(GNs),were used to modulate the mechanical properties and anisotropy of the magnets.It is found that the rodshaped CNTs can increase the bending strength ratio of the c and a axes of the magnet from 1.114 to1.254,while flake-like GNs decrease it from 1.114 to 0.989.In-depth analysis indicates that the mechanical anisotropy of the magnet is greatly influenced by the distribution and thickness of the rare earth phase(RE phase),with the thicker RE phase demonstrating greater capability of blunting at the crack tip.Using the finite element method,it is found that the strength of brittle material can be enhanced by the additive particles owing to the inhibition of crack initiation and stress conduction,as well as the deflection of the crack.The flake-like GNs weaken the mechanical anisotropy of magnets by varying the distribution of RE phase and form a shell encompassing the main phase.Nonetheless,the alignment of CNTs occurring in the process of magnetic orientation process can significantly increase the mechanical anisotropy of the magnet.In particular,when loaded in the parallel c axis(c_(‖))direction,the cracks need to penetrate the main phase due to the strong frictional interlocking between CNTs and the main phase grains,in which case the bending strength will be significantly increased.By contrast,when loaded in the vertical c axis(c_(⊥))direction,the cracks can bypass the rod-like particles and change directions of propagation.As such,the increase in bending strength is smaller than that in loading along with the cll direction.展开更多
In object oriented paradigm, cohesion of a class refers to the degree to which members of the class are interrelated. Metrics have been defined to measure cohesiveness of a class both at design and source code levels....In object oriented paradigm, cohesion of a class refers to the degree to which members of the class are interrelated. Metrics have been defined to measure cohesiveness of a class both at design and source code levels. In comparison to source code level class cohesion metrics, only a few design level class cohesion metrics have been proposed. Design level class cohesion metrics are based on the assumption that if all the methods of a class have access to similar para-meter types then they all process closely related information. A class with a large number of parameter types common in its methods is more cohesive than a class with less number of parameter types common in its methods. In this paper, we review the design level class cohesion metrics with a special focus on metrics which use similarity of parameter types of methods of a class as the basis of its cohesiveness. Basically three metrics fall in this category: Cohesion among Methods of a Class (CAMC), Normalized Hamming Distance (NHD), and Scaled NHD (SNHD). Keeping in mind the anomalies in the definitions of the existing metrics, a variant of the existing metrics is introduced. It is named NHD Modified (NHDM). An automated metric collection tool is used to collect the metric data from an open source software program. The metric data is then subjected to statistical analysis.展开更多
Objectives To compare respiratory parameters of peripheral blood mononuclear cell mitochondria and iron metabolism indicators in patients with different NYHA functional classes of ischemic heart failure(HF).Methods Th...Objectives To compare respiratory parameters of peripheral blood mononuclear cell mitochondria and iron metabolism indicators in patients with different NYHA functional classes of ischemic heart failure(HF).Methods This single center, prospective, non-blinded study enrolled 20 patients with diagnosed chronic HF of ischemic genesis with reduced and mildly reduced left ventricle ejection fraction. The maximum oxygen consumption at the peak of the exercise test(VO2peak), iron metabolism parameters and respiratory activity of peripheral blood mononuclear cell mitochondria were assessed.Results Among the patients, a half of individuals were diagnosed with iron deficiency. Subgroups of patients with different HF severity did not significant differ in VO2peak(P=0.209), serum iron(P=0.468) and ferritin(P=0.235) levels. But there was a trend in increasing in these parameters with increasing NYHA HF functional class. Respiratory control coefficient(RC) in NADdependent and FAD-dependent mitochondrial oxidation were lower in patients with NYHA HF Ⅲ functional class compared to individuals with NYHA HF I functional class(P=0.028 and P=0.040, respectively). Serum iron(P=0.026), ferritin(P=0.045)levels, transferrin saturation(P=0.006) were negatively correlated with RC in NAD-dependent mitochondrial oxidation.Conclusions In aggravation of ischemic HF NYHA FC, there is a decrease in RC of PBMC mitochondria during the oxidation of NAD-dependent and FAD-dependent substrates. In the whole sample, patients with laboratory-confirmed iron deficiency accounted a half of the total number. Iron metabolism parameters had a paradoxical inverse relationship with the level of RC in PBMC mitochondria of patients with HF.展开更多
For concrete situation of class teaching of landscape type of public elective course,the application situation of leading-subject teaching method in specific landscape type of course is explored. Teaching method trans...For concrete situation of class teaching of landscape type of public elective course,the application situation of leading-subject teaching method in specific landscape type of course is explored. Teaching method transforms from "teaching as the center" to "learning as the center". By improving student's learning interest and efficiency,student's whole development and creativity are promoted.展开更多
Class cohesion is considered as one of the most important object-oriented software attributes. High cohesion is, in fact, a desirable property of software. Many different metrics have been suggested in the last severa...Class cohesion is considered as one of the most important object-oriented software attributes. High cohesion is, in fact, a desirable property of software. Many different metrics have been suggested in the last several years to measure the cohesion of classes in object-oriented systems. The class of structural object-oriented cohesion metrics is the most in-vestigated category of cohesion metrics. These metrics measure cohesion on structural information extracted from the source code. Empirical studies noted that these metrics fail in many situations to properly reflect cohesion of classes. This paper aims at exploring the use of hierarchical clustering techniques to improve the measurement of cohesion of classes in object-oriented systems. The proposed approach has been evaluated using three particular case studies. We also used in our study three well-known structural cohesion metrics. The achieved results show that the new approach appears to better reflect the cohesion (and structure) of classes than traditional structural cohesion metrics.展开更多
“Four classes of enterprises above designated size”(hereinafter called four-classes enterprises)refer to objects of statistical survey that have reached a certain scale in China’s current statistical method system,...“Four classes of enterprises above designated size”(hereinafter called four-classes enterprises)refer to objects of statistical survey that have reached a certain scale in China’s current statistical method system,including four classes in national economy,namely,industrial enterprises above designated size,construction and real estate development and management enterprises above qualifications,wholesale and retail,catering and accommodation enterprises,and service enterprises above designated size,which are the primary part of national economic and social development activities.This paper is focused on analyzing the practice and difficulties in the current statistics work of four-classes enterprises,and then this paper proposes some recommendations.展开更多
In order to explore the teaching method of junior high school physics exercise class under the new curriculum standard, and improve students' academic performance.In the early stage of this paper, we selected new ...In order to explore the teaching method of junior high school physics exercise class under the new curriculum standard, and improve students' academic performance.In the early stage of this paper, we selected new teaching methods through literature research. After screening and promoting several teaching methods, we determined the most appropriate teaching method through questionnaire.After the implementation of the teaching method, the students'liking degree of physics class has been significantly improved. The course mode that students like is more autonomous communication. More than 80% of the students can complete the teacher& apos;shomework on time. The problems encountered in the learning process are not waiting for the teacher's explanation, not searching for solutions on the Internet, but communicating with classmates to find appropriate explanation methods, and some of them will Think independently and find your own way.In the process of teaching reform, most students have learned to think and summarize. They can find the key points in class more clearly than before. They can review the wrong exercises many times and establish their own exercise set.After a period of research, it is found that compared with the traditional teaching mode, the new teaching mode is more diversified, which is more conducive to stimulate students'interest and enthusiasm, to cultivate students'subjective initiative to participate in physics exercise class, and to better develop students'autonomous learning potential.展开更多
基金The National Natural Science Foundation of China(No.60425206,60633010)the High Technology Research and Development Program of Jiangsu Province(No.BG2005032)
文摘This paper suggests that a single class rather than methods should be used as the slice scope to compute class cohesion. First, for a given attribute, the statements in all methods that last define the attribute are computed. Then, the forward and backward data slices for this attribute are generated by using the class as the slice scope and are combined to compute the corresponding class data slice. Finally, the class cohesion is computed based on all class data slices for the attributes. Compared to traditional cohesion metrics that use methods as the slice scope, the proposed metrics that use a single class as slice scope take into account the possible interactions between the methods. The experimental results show that class cohesion can be more accurately measured when using the class as the slice scope.
基金supported by the National Natural Science Foundation of China(52074313).
文摘The migration,accumulation,and high yield of hydrocarbons in tight sandstone reservoirs are closely tied to the natural fracture systems within the reservoirs.Large-scale fracture networks not only enhance reservoir seepage capacity but also influence effective productivity and subsequent fracturing reconstruction.Given the diverse mechanical behaviors,such as migration,penetration,or fracture arrest,traditional assumptions about fracture interaction criteria fail to address this complexity.To resolve these issues,a global cohesive element method is proposed to model random natural fractures.This approach verifies intersection models based on real-time stress conditions rather than pre-set criteria,enabling better characterization of interactions between hydraulic and natural fractures.Research has shown that the elastic modulus,horizontal stress difference,and fracturing fluid pumping rate significantly promote the expansion of hydraulic fractures.The use of low viscosity fracturing fluid can observe a decrease in the width of fractures near the wellbore,which may cause fractures to deflect when interacting with natural fractures.However,simulations under these conditions did not form a“complex network of fractures”.It is worth noting that when the local stress difference is zero,the result is close to the formation of this network.Excessive spacing will reduce the interaction between fractures,resulting in a decrease in the total length of fractures.By comprehensively analyzing these factors,an optimal combination can be identified,increasing the likelihood of achieving a“complex fracture network”.This paper thoroughly investigates hydraulic fracture propagation in naturally fractured reservoirs under various conditions,offering insights for developing efficient fracturing methods.
文摘Slope failures,particularly in railway embankments during intense rainfall,are a major cause of economic damage and humanitarian loss.To forecast how shear cracks develop in slopes under heavy precipitation,we present a novel modeling framework:the Extended Cohesive Damage Element enhanced by soil moisture(SMECDE).The method first translates forecasted rainfall into soil moisture levels via an established correspondence.Then,recognizing that rainfall infiltration lowers soil cohesion—particularly at varying depths—we introduce a Soil Moisture Decoherence Model(SMDM)based on experimental data,which quantifies how cohesion degrades with moisture and how depth affects this process.By embedding SMDM within the ECDE technique,we investigate how shear fractures propagate under different moisture conditions throughout the slope profile.We apply SMECDE to a real railway embankment case to identify critical moisture thresholds and crack growth patterns.Validation is performed by comparing predictions against field measurements and weather station records,and further checked through simulations of large-scale plastic deformation in ABAQUS.
基金Supported by National Natural Science Foundation of China(Grant No.11971015).
文摘The goal of this paper is to investigate the theory of Noether solvability for Volterra singular integral equations(VSIEs)with convolution and Cauchy kernels in a more general function class.To obtain the analytic solutions,we transform such equations into boundary value problems with discontinuous coefficients by the properties of Fourier analysis.In view of the analytical Riemann-Hilbert method,the generalized Liouville theorem and Sokhotski-Plemelj formula,we get the uniqueness and existence of solutions for such problems,and study the asymptotic property of solutions at nodes.Therefore,this paper improves the theory of singular integral equations and boundary value problems.
基金Supported by the Science Research Foundation(2010Y290) of Yunnan Department of Education
文摘As the key technology of extracting remote sensing information,the classification of remote sensing images has always been the research focus in the field of remote sensing. The paper introduces the classification process and system of remote sensing images. According to the recent research status of domestic and international remote sensing classification methods,the new study dynamics of remote sensing classification,such as artificial neural networks,support vector machine,active learning and ensemble multi-classifiers,were introduced,providing references for the automatic and intelligent development of remote sensing images classification.
基金supported by project funding from Chongqing Normal University (No. 12XLB009)Key Projects in the National Science & Technology Program (No. 2006BAD26B0302)
文摘Grain-size class-Std(GSCStd) and Grain-size class-dD(GSCdD) methods are simple statistical approaches for classifying bulk grain-size distributions(GSDs) into grain-size fractions. Although these two methods were developed based on similar statistical principles, the classification difference between these two methods has not been analyzed. In this study, GSCStd and GSCdD methods are conducted in thirteen grain-size data sequences to examine the applicability for identifying grain size fractions. Results show that, application of the GSCStd method is equivalent to that of the GSCdD method in identifying finer grain-size fractions, and the difference between the two methods mainly comes from the identification of coarse grain-size fractions. Thus, finer grain-size fractions are recommended for use in research of surface aeolian and paleo-aeolian sediments. In addition, our results do not completely agree with previous studies, coarser grain-size fractions in our case suggest that the GSCdD method may not be more applicable than the GSCStd method.
文摘With the development of social civilization, people's spiritual pursuit is constantly changing and more and more attention is paid to education reform. It is very important to innovate the way of education and teaching, to perfect the system of education and teaching and to dig the inner potential of students deeply, so as to cultivate a large number of high-quality talents, which is conducive to the new success of the modernization of society. During the period of secondary vocational education, it is the duty of the head teacher to continuously strengthen class management, care about students' study and life, and further enhance students' sense of ownership. This article specially from several aspects, on the teacher in charge of secondary vocational management of the class methods and skills were summarized and analyzed.
基金Project supported by the National Natural Science Foundation of China.
文摘In this note,the explicit form of the N soliton solutions for a class of the system of LS nonlinear wave interaction have been obtained by using Hirota's method.
文摘The acoustic vibration signal of tank is disassembled into the sum of intrinsic mode function （IMF） by multi-resolution empirical mode decomposition （EMD） method. The instantaneous frequency is obtained, and feature transformation matrix is figured out by class scatter matrix. Multi- dimensional scale energy vector is mapped into low-dimensional eigenvector, and classification extraction is realized. This method sufficiently separates of different sound target features. The test result indicates that it is effective.
文摘The interaction between the classes or within the classes shows the complexity of the design. For one smaller problem, there may be more than one software design but who will be the best;depends on the complexity level of software design. Therefore, coupling and cohesion which shows the interlinking of classes and strength of classes;control the complexity of the design. The best software object oriented design is based upon the low coupling and high cohesion level. In the present work, a real case study of Life Insurance policy for handicapped person is demonstrated through the UML Class Diagram;coupling and cohesion levels are measured and results are demonstrated in the form of tables.
文摘Music situational teaching method aims to mobilize the students’thoughts in a natural state so as to enhance the attractiveness and efficiency of music classes.In the process of this method,some specific situational are designed according to the characteristics of music and under the guidance of psychology,methodology,pedagogy and other theories,and various sensory organs are employed.Different from traditional teaching method,situational teaching method creates learning situational for students,which is consistent with the characteristics of primary school students’physical and mental development and maximizes students’experience and feeling of music.
文摘In this study,an alternative modelling approach for absorbed hydrogen stress corrosion cracking(SCC)is proposed,with hydrogen-enhanced decohesion(HEDE)identified as the key failure mechanism.All analyses have been performed by utilising only ABAQUS standard elements,COH2D4T and CPE4T,already available within the software and without the need to develop external subroutines.The study also tends to highlight the criticality of implementing a correct Traction Separation Law(TSL)curve to simulate the hydrogen diffusion within the specimen and using the concept of dynamic hydrogen penetration by continuously updating the hydrogen concentration boundary conditions as the crack propagates.In conclusion,this study successfully demonstrated that standard software elements(COH2D4T and CPE4T)can effectively model physical problems and crack velocity propagation without custom subroutines.It emphasized that while the specific shape of the Traction-Separation Law(TSL)is less critical,its correct implementation is vital for simulating dynamic hydrogen coverage.Crucially,excluding this dynamic coverage—a common practice—risks significantly underestimating crack propagation speed.Although results incorporating dynamic coverage aligned well with experimental data,minor discrepancies are likely due to unmodeled factors like material property variations,hydrogen trapping,temperature,and granular microstructure,which are proposed for future research.
基金Project supported by National Key R&D Project of China(2022YFB3505400)Jiangxi Natural Science Foundation Youth Fund(20232BAB214011)+3 种基金the Young Elite Scientists Sponsorship Program by CAST(2022QNRC001)National Natural Science Foundation of China(52361033)Ministry of Industry and Information Technology Heavy Rare Earth Special Use of Sintered NdFeB Project(TC220H06J)Academic and Technical Leaders in Major Disciplines in Jiangxi Province(20225BCJ23007)。
文摘The particles of different shapes,multi-walled carbon nanotubes(CNTs)and graphene nanosheets(GNs),were used to modulate the mechanical properties and anisotropy of the magnets.It is found that the rodshaped CNTs can increase the bending strength ratio of the c and a axes of the magnet from 1.114 to1.254,while flake-like GNs decrease it from 1.114 to 0.989.In-depth analysis indicates that the mechanical anisotropy of the magnet is greatly influenced by the distribution and thickness of the rare earth phase(RE phase),with the thicker RE phase demonstrating greater capability of blunting at the crack tip.Using the finite element method,it is found that the strength of brittle material can be enhanced by the additive particles owing to the inhibition of crack initiation and stress conduction,as well as the deflection of the crack.The flake-like GNs weaken the mechanical anisotropy of magnets by varying the distribution of RE phase and form a shell encompassing the main phase.Nonetheless,the alignment of CNTs occurring in the process of magnetic orientation process can significantly increase the mechanical anisotropy of the magnet.In particular,when loaded in the parallel c axis(c_(‖))direction,the cracks need to penetrate the main phase due to the strong frictional interlocking between CNTs and the main phase grains,in which case the bending strength will be significantly increased.By contrast,when loaded in the vertical c axis(c_(⊥))direction,the cracks can bypass the rod-like particles and change directions of propagation.As such,the increase in bending strength is smaller than that in loading along with the cll direction.
文摘In object oriented paradigm, cohesion of a class refers to the degree to which members of the class are interrelated. Metrics have been defined to measure cohesiveness of a class both at design and source code levels. In comparison to source code level class cohesion metrics, only a few design level class cohesion metrics have been proposed. Design level class cohesion metrics are based on the assumption that if all the methods of a class have access to similar para-meter types then they all process closely related information. A class with a large number of parameter types common in its methods is more cohesive than a class with less number of parameter types common in its methods. In this paper, we review the design level class cohesion metrics with a special focus on metrics which use similarity of parameter types of methods of a class as the basis of its cohesiveness. Basically three metrics fall in this category: Cohesion among Methods of a Class (CAMC), Normalized Hamming Distance (NHD), and Scaled NHD (SNHD). Keeping in mind the anomalies in the definitions of the existing metrics, a variant of the existing metrics is introduced. It is named NHD Modified (NHDM). An automated metric collection tool is used to collect the metric data from an open source software program. The metric data is then subjected to statistical analysis.
基金supported by Russian Science Foundation,RSF 23-75-00009(part of the study corresponding to finding 1)Part of the study corresponding to finding 2 was carried out within the state assignment,FSR No.:122020300045-5(03.02.2022).
文摘Objectives To compare respiratory parameters of peripheral blood mononuclear cell mitochondria and iron metabolism indicators in patients with different NYHA functional classes of ischemic heart failure(HF).Methods This single center, prospective, non-blinded study enrolled 20 patients with diagnosed chronic HF of ischemic genesis with reduced and mildly reduced left ventricle ejection fraction. The maximum oxygen consumption at the peak of the exercise test(VO2peak), iron metabolism parameters and respiratory activity of peripheral blood mononuclear cell mitochondria were assessed.Results Among the patients, a half of individuals were diagnosed with iron deficiency. Subgroups of patients with different HF severity did not significant differ in VO2peak(P=0.209), serum iron(P=0.468) and ferritin(P=0.235) levels. But there was a trend in increasing in these parameters with increasing NYHA HF functional class. Respiratory control coefficient(RC) in NADdependent and FAD-dependent mitochondrial oxidation were lower in patients with NYHA HF Ⅲ functional class compared to individuals with NYHA HF I functional class(P=0.028 and P=0.040, respectively). Serum iron(P=0.026), ferritin(P=0.045)levels, transferrin saturation(P=0.006) were negatively correlated with RC in NAD-dependent mitochondrial oxidation.Conclusions In aggravation of ischemic HF NYHA FC, there is a decrease in RC of PBMC mitochondria during the oxidation of NAD-dependent and FAD-dependent substrates. In the whole sample, patients with laboratory-confirmed iron deficiency accounted a half of the total number. Iron metabolism parameters had a paradoxical inverse relationship with the level of RC in PBMC mitochondria of patients with HF.
基金Sponsored by Teaching Research and Reform Project of Undergraduate Education from Southwest Jiaotong University
文摘For concrete situation of class teaching of landscape type of public elective course,the application situation of leading-subject teaching method in specific landscape type of course is explored. Teaching method transforms from "teaching as the center" to "learning as the center". By improving student's learning interest and efficiency,student's whole development and creativity are promoted.
文摘Class cohesion is considered as one of the most important object-oriented software attributes. High cohesion is, in fact, a desirable property of software. Many different metrics have been suggested in the last several years to measure the cohesion of classes in object-oriented systems. The class of structural object-oriented cohesion metrics is the most in-vestigated category of cohesion metrics. These metrics measure cohesion on structural information extracted from the source code. Empirical studies noted that these metrics fail in many situations to properly reflect cohesion of classes. This paper aims at exploring the use of hierarchical clustering techniques to improve the measurement of cohesion of classes in object-oriented systems. The proposed approach has been evaluated using three particular case studies. We also used in our study three well-known structural cohesion metrics. The achieved results show that the new approach appears to better reflect the cohesion (and structure) of classes than traditional structural cohesion metrics.
文摘“Four classes of enterprises above designated size”(hereinafter called four-classes enterprises)refer to objects of statistical survey that have reached a certain scale in China’s current statistical method system,including four classes in national economy,namely,industrial enterprises above designated size,construction and real estate development and management enterprises above qualifications,wholesale and retail,catering and accommodation enterprises,and service enterprises above designated size,which are the primary part of national economic and social development activities.This paper is focused on analyzing the practice and difficulties in the current statistics work of four-classes enterprises,and then this paper proposes some recommendations.
文摘In order to explore the teaching method of junior high school physics exercise class under the new curriculum standard, and improve students' academic performance.In the early stage of this paper, we selected new teaching methods through literature research. After screening and promoting several teaching methods, we determined the most appropriate teaching method through questionnaire.After the implementation of the teaching method, the students'liking degree of physics class has been significantly improved. The course mode that students like is more autonomous communication. More than 80% of the students can complete the teacher& apos;shomework on time. The problems encountered in the learning process are not waiting for the teacher's explanation, not searching for solutions on the Internet, but communicating with classmates to find appropriate explanation methods, and some of them will Think independently and find your own way.In the process of teaching reform, most students have learned to think and summarize. They can find the key points in class more clearly than before. They can review the wrong exercises many times and establish their own exercise set.After a period of research, it is found that compared with the traditional teaching mode, the new teaching mode is more diversified, which is more conducive to stimulate students'interest and enthusiasm, to cultivate students'subjective initiative to participate in physics exercise class, and to better develop students'autonomous learning potential.
