This paper presents a generalization of the authors＇ earlier work. In this paper, the two concepts, generic regular decomposition （GRD） and regular-decomposition-unstable （RDU） variety introduced in the authors＇...This paper presents a generalization of the authors＇ earlier work. In this paper, the two concepts, generic regular decomposition （GRD） and regular-decomposition-unstable （RDU） variety introduced in the authors＇ previous work for generic zero-dimensional systems, are extended to the case where the parametric systems are not necessarily zero-dimensional. An algorithm is provided to compute GRDs and the associated RDU varieties of parametric systems simultaneously on the basis of the algorithm for generic zero-dimensional systems proposed in the authors＇ previous work. Then the solutions of any parametric system can be represented by the solutions of finitely many regular systems and the decomposition is stable at any parameter value in the complement of the associated RDU variety of the parameter space. The related definitions and the results presented in the authors＇ previous work are also generalized and a further discussion on RDU varieties is given from an experimental point of view. The new algorithm has been implemented on the basis of DISCOVERER with Maple 16 and experimented with a number of benchmarks from the literature.展开更多
In this book new results on controller design techniques for the tracking of generic reference inputs are presented. They allow the design of a controller for an uncertain process, either continuous or discrete-time, ...In this book new results on controller design techniques for the tracking of generic reference inputs are presented. They allow the design of a controller for an uncertain process, either continuous or discrete-time, without zeros, and with measurable state. The controller guarantees that the control system is Type 1 and has the desired constant gain and poles or that the control system tracks, with a specified maximum error and with a specified maximum time constant, a generic reference with bounded derivative (variation in the discrete-time case), also in the presence of a generic disturbance with bounded derivative (variation). In addition, it is considered the case in which the reference is known a priori. The utility and the efficiency of the proposed methods are illustrated with attractive and significant examples of motion control and temperature control. This book is useful for the design of control systems, especially for manufacturing systems, that are versatile, fast, precise and robust.展开更多
Significant progress has been made in computational imaging(CI),in which deep convolutional neural networks(CNNs)have demonstrated that sparse speckle patterns can be reconstructed.However,due to the limited“local”k...Significant progress has been made in computational imaging(CI),in which deep convolutional neural networks(CNNs)have demonstrated that sparse speckle patterns can be reconstructed.However,due to the limited“local”kernel size of the convolutional operator,for the spatially dense patterns,such as the generic face images,the performance of CNNs is limited.Here,we propose a“non-local”model,termed the Speckle-Transformer(SpT)UNet,for speckle feature extraction of generic face images.It is worth noting that the lightweight SpT UNet reveals a high efficiency and strong comparative performance with Pearson Correlation Coefficient(PCC),and structural similarity measure(SSIM)exceeding 0.989,and 0.950,respectively.展开更多
The development of ubiquitous computing systems benefits tremendously from the service-oriented computing concept in seamless interoperation of heterogeneous devices. However, architectures, services interfaces and ne...The development of ubiquitous computing systems benefits tremendously from the service-oriented computing concept in seamless interoperation of heterogeneous devices. However, architectures, services interfaces and network implementation of the existing service-oriented systems differ case by case. Furthermore, many systems lack the capability of being applied to resource constrained devices, for example, sensors. Therefore, we propose a standardized approach to present a service to the network and to access a networked service, which can be adopted by arbitrary types of devices. In this approach, services are specified and exposed through a set of standardized interfaces. Moreover, a virtual community concept is introduced to determine a secure boundary within which services can be freely discovered, accessed and composed into applications;a hierarchical management scheme is presented which enables the third party management of services and their underlying resources. In this way, application control logic goes into the network and environment context is dealt with intelligently by the system. A prototype system is developed to validate our ideas. Results show the feasibility of this open distributed system software architecture.展开更多
Objective To study the significance of authorized generic drugs due to the successive relevant documents issued by China’s government in recent years,which clearly stipulated that China should establish a drug patent...Objective To study the significance of authorized generic drugs due to the successive relevant documents issued by China’s government in recent years,which clearly stipulated that China should establish a drug patent linkage system.Methods The authorized generic drugs play an important role in keeping the balance between brandname drugs and generic drugs in the US.Therefore,this system was investigated,focusing on its difference from independent generics,marketing procedures,application in patent litigation and legitimacy analysis through case evidence.This analogy analysis could provide a reference for the research of authorized generic drug systems in China.Results and Conclusion As an important factor affecting the balance between brand-name drugs and generic drugs,authorized generic drugs should be comprehensively analyzed and discussed,and a suitable system for China’s national conditions should be established by referring to the experiences of the US.展开更多
Rock mass classification(RMC) is of critical importance in support design and applications to mining,tunneling and other underground excavations. Although a number of techniques are available, there exists an uncertai...Rock mass classification(RMC) is of critical importance in support design and applications to mining,tunneling and other underground excavations. Although a number of techniques are available, there exists an uncertainty in application to complex underground works. In the present work, a generic rock mass rating(GRMR) system is developed. The proposed GRMR system refers to as most commonly used techniques, and two rock load equations are suggested in terms of GRMR, which are based on the fact that whether all the rock parameters considered by the system have an influence or only few of them are influencing. The GRMR method has been validated with the data obtained from three underground coal mines in India. Then, a semi-empirical model is developed for the GRMR method using artificial neural network(ANN), and it is validated by a comparative analysis of ANN model results with that by analytical GRMR method.展开更多
Attribute-based encryption is drawing more attention with its inherent attractive properties which are potential to be widely used in the newly developing cloud computing. However, one of the main obstacles for its ap...Attribute-based encryption is drawing more attention with its inherent attractive properties which are potential to be widely used in the newly developing cloud computing. However, one of the main obstacles for its application is how to revoke the attributes of the users, though some ABE schemes have realized revocation, they mostly focused on the user revocation that revokes the user＇s whole attributes, or attribute revocation under the indirect revocation model such that all the users＇ private keys will be affected by the revocation. In this paper, we define the model of CP-ABE supporting the attribute revocation under the direct revocation model, in which the revocation list is embed in the ciphertext and none of the users＇ private keys will be affected by the revocation process. Then we propose a generic construction, and prove its security with the decision q-BDHE assumption.展开更多
Dasatinib is a second-generation tyrosine kinase inhibitor (TKI)and it could be used as a second-line treatment for patients with chronic myeloid leukemia (CML).Yinishu,a generic dasatinib made in China,was approved b...Dasatinib is a second-generation tyrosine kinase inhibitor (TKI)and it could be used as a second-line treatment for patients with chronic myeloid leukemia (CML).Yinishu,a generic dasatinib made in China,was approved by the China Food and Drug Administration in 2013 and it costs much less than the patented dasatinib SPRYCEL.The present study aimed to examine the efficacy and safety of Yinishu as a second-line treatment for CML by comparing the baseline clinical characteristics,rates of adverse events and efficacy between Yinishu and SPRYCEL groups. The results showed that there were no significant differences in the rates of optimal response between Yinishu and SPRYCEL for patients who started second-line treatment because of treatment failure.For patients who started second-line treatment because of intolerance of first-line treatment, their levels of BCR-ABL1/ABL1 on the international scale (BCR-ABL^IS)was maintained very low throughout the course of Yinishu treatment.Drug-related adverse events occurred with the same frequency in these two groups.It was confirmed that Yinishu was effective and safe as a second- line treatment for CML patients.Yinishu may be more suitable for patients who are economically unable to pay for the patented dasatinib SPRYCEL.展开更多
In this paper, we report the results of quality control based in pbysicochemical characteriza- tion and impurities determination of three samples of fluconazole drug substances marketed in Morocco. These samples were ...In this paper, we report the results of quality control based in pbysicochemical characteriza- tion and impurities determination of three samples of fluconazole drug substances marketed in Morocco. These samples were supplied by different pharmaceuticals companies. The sample A, as the discovered product, was supplied by Pfizer, while samples B and C （generics）, were manufactured by two different Indian industries. Solid-state characterization of the three samples was realized with different physicochemical methods as： X-ray powder diffraction, Fourier-transformation infrared spectroscopy, differential scanning calorimetry. High performance liquid chromatography was used to quantify the impurities in the different samples. The results from the physicochemical methods cited above, showed difference in polymorph structure of the three drug substances. Sample A consisted in pure polymorph II1, sample B consisted in pure polymorph I1, sample C consisted in a mixture of fluconazole Form Ili, form II and the monohydrate. This result was confirmed by differential scanning calorimetry. Also it was demonstrated that solvents used during the re-crystallization step were among the origins of these differences in the structure form. On the other hand, the result of the stability study under humidity and temperature showed that fluconazole polymorphic transformation could be owed to the no compliance with the conditions of storage. The HPLC analysis of these compounds showed the presence of specific展开更多
In more recent times, health-related quality of life (HRQOL) measurements have formed an important part of as- sessing the quality of routine care in general practice. For a measure to have clinical usefulness it must...In more recent times, health-related quality of life (HRQOL) measurements have formed an important part of as- sessing the quality of routine care in general practice. For a measure to have clinical usefulness it must not only be valid, appro- priate, reliable, responsive, and capable of being interpreted, but it must also be simple, fast to complete, easy to score, and provide useful clinical data. The Two-step method of choosing appropriate measures is introduced. Then through comparison of generic instruments with disease-specific instruments, we can conclude that sometimes a combination of generic and disease-specific HRQOL measures may be more appropriate for monitoring changes in a patient’s health status due to an intervention.展开更多
Actinomycetes population from continental slope sediment of the Bay of Bengal was studied. Samples were collected during two voyages of FORV Sagar Sampada in 2004 （May-June） and 2005 （July） respectively from 11 tr...Actinomycetes population from continental slope sediment of the Bay of Bengal was studied. Samples were collected during two voyages of FORV Sagar Sampada in 2004 （May-June） and 2005 （July） respectively from 11 transects （each transect had ca. 200 m, 500 m, and 1 000 m depth stations）. The physicochemical parameters of overlying water, and sediment samples were also recorded. The actinomycete population ranged from 5.17 to 51.94 CFU/g dry sediment weight and 9.38 to 45.22 CFU/g dry sediment weight during the two cruises respectively. No actinomycete colony was isolated from stations in 1 000 m depth. Two-way analysis of variance showed significant variation among stations （ANOVA two-way, P〈0.05）, but no significance was found between the two cruises （ANOVA two-way, P〈0.05）. Populations in stations in 500 m depth in both cruises were higher than that of 200 m depth stations with statistically insignificant difference （ANOVA two-way, P〉0.05）. Three actinomycetes genera were identified. Streptomyces was found to be the dominating one in both the cruises, followed by Micromonospora, and Actinomyces. The spore of Streptomyces isolates showed the abundance in spiral spore chain. Spore surface was smooth. Multiple regression analysis revealed that the influencing physico-chemical factors were sediment pH, sediment temperature, TOC, porosity, salinity, and pressure. The media used in the present study was prepared with seawater. Thus, they may represent an autochthonous marine flora and deny the theory of land runoff carriage into the sea for adaptation to the salinity of the seawater and sediments.展开更多
Objective:Generic drugs provide an opportunity for savings in drug expenditure since they are available at a lower cost and do not affect patients’health.A better understanding of pharmacists’knowledge,attitudes,and...Objective:Generic drugs provide an opportunity for savings in drug expenditure since they are available at a lower cost and do not affect patients’health.A better understanding of pharmacists’knowledge,attitudes,and perception can promote the quality use of generic drugs.The objective of this study was to investigate the knowledge,attitudes,and perception of pharmacists from tertiary hospitals in China regarding generic drugs.Methods:A cross-sectional survey using a postal questionnaire was conducted,which was sent to 200 hospital pharmacists randomly selected from tertiary hospitals in Hubei Province.A total of 125 questionnaires out of 200 were received.Of the respondents,80 were female and 45 were male.Results:The majority of respondents(87.2%)could clearly distinguish between original and generic drugs.Pharmacists agreed that generic drugs were less effective(52.8%)and produced more side effects(52%).Forty-nine respondents thought that generic drug products were not adequately tested.Approximately 78% and 60% of the pharmacists indicated that generic substitution was not feasible for drugs with narrow therapeutic windows and drugs for critical diseases,respectively.Most of them supported the recommendation of generic drugs based on professional judgment.Conclusion:Our study showed that a considerable portion of Chinese hospital pharmacists hold negative perceptions of generic drugs.Interventions to improve pharmacists'knowledge of generic drugs are needed.展开更多
We prove that a Cl-generic volume-preserving dynamical system （diffeomor- phism or flow） has the shadowing property or is expansive or has the weak specification property if and only if it is Anosov. Finally, as in ...We prove that a Cl-generic volume-preserving dynamical system （diffeomor- phism or flow） has the shadowing property or is expansive or has the weak specification property if and only if it is Anosov. Finally, as in [10, 27], we prove that the Cl-robustness, within the volume-preserving context, of the expansiveness property and the weak specifica- tion property, imply that the dynamical system （diffeomorphism or flow） is Anosov.展开更多
We use Hopf-Lax formula to study local regularity of solution to Hamilton- Jacobi （HJ） equations of multi-dimensional space variables with convex Hamiltonian. Then we give the large time generic form of the solution...We use Hopf-Lax formula to study local regularity of solution to Hamilton- Jacobi （HJ） equations of multi-dimensional space variables with convex Hamiltonian. Then we give the large time generic form of the solution to HJ equation, i.e. for most initial data there exists a constant T 〉 0, which depends only on the Hamiltonian and initial datum, for t 〉 T the solution of the IVP （1.1） is smooth except for ~ smooth n-dimensional hypersurface, across which Du（x, t） is discontinuous. And we show that the hypersurface 1 tends asymptotically to a given hypersurface with rate t-1/4.展开更多
基金supported by by the National Natural Science Foundation of China under Grant Nos.11271034,11290141the Project SYSKF1207 from SKLCS,IOS,the Chinese Academy of Sciences
文摘This paper presents a generalization of the authors＇ earlier work. In this paper, the two concepts, generic regular decomposition （GRD） and regular-decomposition-unstable （RDU） variety introduced in the authors＇ previous work for generic zero-dimensional systems, are extended to the case where the parametric systems are not necessarily zero-dimensional. An algorithm is provided to compute GRDs and the associated RDU varieties of parametric systems simultaneously on the basis of the algorithm for generic zero-dimensional systems proposed in the authors＇ previous work. Then the solutions of any parametric system can be represented by the solutions of finitely many regular systems and the decomposition is stable at any parameter value in the complement of the associated RDU variety of the parameter space. The related definitions and the results presented in the authors＇ previous work are also generalized and a further discussion on RDU varieties is given from an experimental point of view. The new algorithm has been implemented on the basis of DISCOVERER with Maple 16 and experimented with a number of benchmarks from the literature.
文摘In this book new results on controller design techniques for the tracking of generic reference inputs are presented. They allow the design of a controller for an uncertain process, either continuous or discrete-time, without zeros, and with measurable state. The controller guarantees that the control system is Type 1 and has the desired constant gain and poles or that the control system tracks, with a specified maximum error and with a specified maximum time constant, a generic reference with bounded derivative (variation in the discrete-time case), also in the presence of a generic disturbance with bounded derivative (variation). In addition, it is considered the case in which the reference is known a priori. The utility and the efficiency of the proposed methods are illustrated with attractive and significant examples of motion control and temperature control. This book is useful for the design of control systems, especially for manufacturing systems, that are versatile, fast, precise and robust.
基金funding support from the Science and Technology Commission of Shanghai Municipality(Grant No.21DZ1100500)the Shanghai Frontiers Science Center Program(2021-2025 No.20)+2 种基金the Zhangjiang National Innovation Demonstration Zone(Grant No.ZJ2019ZD-005)supported by a fellowship from the China Postdoctoral Science Foundation(2020M671169)the International Postdoctoral Exchange Program from the Administrative Committee of Post-Doctoral Researchers of China([2020]33)。
文摘Significant progress has been made in computational imaging(CI),in which deep convolutional neural networks(CNNs)have demonstrated that sparse speckle patterns can be reconstructed.However,due to the limited“local”kernel size of the convolutional operator,for the spatially dense patterns,such as the generic face images,the performance of CNNs is limited.Here,we propose a“non-local”model,termed the Speckle-Transformer(SpT)UNet,for speckle feature extraction of generic face images.It is worth noting that the lightweight SpT UNet reveals a high efficiency and strong comparative performance with Pearson Correlation Coefficient(PCC),and structural similarity measure(SSIM)exceeding 0.989,and 0.950,respectively.
文摘The development of ubiquitous computing systems benefits tremendously from the service-oriented computing concept in seamless interoperation of heterogeneous devices. However, architectures, services interfaces and network implementation of the existing service-oriented systems differ case by case. Furthermore, many systems lack the capability of being applied to resource constrained devices, for example, sensors. Therefore, we propose a standardized approach to present a service to the network and to access a networked service, which can be adopted by arbitrary types of devices. In this approach, services are specified and exposed through a set of standardized interfaces. Moreover, a virtual community concept is introduced to determine a secure boundary within which services can be freely discovered, accessed and composed into applications;a hierarchical management scheme is presented which enables the third party management of services and their underlying resources. In this way, application control logic goes into the network and environment context is dealt with intelligently by the system. A prototype system is developed to validate our ideas. Results show the feasibility of this open distributed system software architecture.
文摘Objective To study the significance of authorized generic drugs due to the successive relevant documents issued by China’s government in recent years,which clearly stipulated that China should establish a drug patent linkage system.Methods The authorized generic drugs play an important role in keeping the balance between brandname drugs and generic drugs in the US.Therefore,this system was investigated,focusing on its difference from independent generics,marketing procedures,application in patent litigation and legitimacy analysis through case evidence.This analogy analysis could provide a reference for the research of authorized generic drug systems in China.Results and Conclusion As an important factor affecting the balance between brand-name drugs and generic drugs,authorized generic drugs should be comprehensively analyzed and discussed,and a suitable system for China’s national conditions should be established by referring to the experiences of the US.
基金an outcome of the Network project(Project No.ESC0303)of CSIR,New Delhi,India
文摘Rock mass classification(RMC) is of critical importance in support design and applications to mining,tunneling and other underground excavations. Although a number of techniques are available, there exists an uncertainty in application to complex underground works. In the present work, a generic rock mass rating(GRMR) system is developed. The proposed GRMR system refers to as most commonly used techniques, and two rock load equations are suggested in terms of GRMR, which are based on the fact that whether all the rock parameters considered by the system have an influence or only few of them are influencing. The GRMR method has been validated with the data obtained from three underground coal mines in India. Then, a semi-empirical model is developed for the GRMR method using artificial neural network(ANN), and it is validated by a comparative analysis of ANN model results with that by analytical GRMR method.
文摘Attribute-based encryption is drawing more attention with its inherent attractive properties which are potential to be widely used in the newly developing cloud computing. However, one of the main obstacles for its application is how to revoke the attributes of the users, though some ABE schemes have realized revocation, they mostly focused on the user revocation that revokes the user＇s whole attributes, or attribute revocation under the indirect revocation model such that all the users＇ private keys will be affected by the revocation. In this paper, we define the model of CP-ABE supporting the attribute revocation under the direct revocation model, in which the revocation list is embed in the ciphertext and none of the users＇ private keys will be affected by the revocation process. Then we propose a generic construction, and prove its security with the decision q-BDHE assumption.
文摘Dasatinib is a second-generation tyrosine kinase inhibitor (TKI)and it could be used as a second-line treatment for patients with chronic myeloid leukemia (CML).Yinishu,a generic dasatinib made in China,was approved by the China Food and Drug Administration in 2013 and it costs much less than the patented dasatinib SPRYCEL.The present study aimed to examine the efficacy and safety of Yinishu as a second-line treatment for CML by comparing the baseline clinical characteristics,rates of adverse events and efficacy between Yinishu and SPRYCEL groups. The results showed that there were no significant differences in the rates of optimal response between Yinishu and SPRYCEL for patients who started second-line treatment because of treatment failure.For patients who started second-line treatment because of intolerance of first-line treatment, their levels of BCR-ABL1/ABL1 on the international scale (BCR-ABL^IS)was maintained very low throughout the course of Yinishu treatment.Drug-related adverse events occurred with the same frequency in these two groups.It was confirmed that Yinishu was effective and safe as a second- line treatment for CML patients.Yinishu may be more suitable for patients who are economically unable to pay for the patented dasatinib SPRYCEL.
文摘In this paper, we report the results of quality control based in pbysicochemical characteriza- tion and impurities determination of three samples of fluconazole drug substances marketed in Morocco. These samples were supplied by different pharmaceuticals companies. The sample A, as the discovered product, was supplied by Pfizer, while samples B and C （generics）, were manufactured by two different Indian industries. Solid-state characterization of the three samples was realized with different physicochemical methods as： X-ray powder diffraction, Fourier-transformation infrared spectroscopy, differential scanning calorimetry. High performance liquid chromatography was used to quantify the impurities in the different samples. The results from the physicochemical methods cited above, showed difference in polymorph structure of the three drug substances. Sample A consisted in pure polymorph II1, sample B consisted in pure polymorph I1, sample C consisted in a mixture of fluconazole Form Ili, form II and the monohydrate. This result was confirmed by differential scanning calorimetry. Also it was demonstrated that solvents used during the re-crystallization step were among the origins of these differences in the structure form. On the other hand, the result of the stability study under humidity and temperature showed that fluconazole polymorphic transformation could be owed to the no compliance with the conditions of storage. The HPLC analysis of these compounds showed the presence of specific
文摘In more recent times, health-related quality of life (HRQOL) measurements have formed an important part of as- sessing the quality of routine care in general practice. For a measure to have clinical usefulness it must not only be valid, appro- priate, reliable, responsive, and capable of being interpreted, but it must also be simple, fast to complete, easy to score, and provide useful clinical data. The Two-step method of choosing appropriate measures is introduced. Then through comparison of generic instruments with disease-specific instruments, we can conclude that sometimes a combination of generic and disease-specific HRQOL measures may be more appropriate for monitoring changes in a patient’s health status due to an intervention.
文摘Actinomycetes population from continental slope sediment of the Bay of Bengal was studied. Samples were collected during two voyages of FORV Sagar Sampada in 2004 （May-June） and 2005 （July） respectively from 11 transects （each transect had ca. 200 m, 500 m, and 1 000 m depth stations）. The physicochemical parameters of overlying water, and sediment samples were also recorded. The actinomycete population ranged from 5.17 to 51.94 CFU/g dry sediment weight and 9.38 to 45.22 CFU/g dry sediment weight during the two cruises respectively. No actinomycete colony was isolated from stations in 1 000 m depth. Two-way analysis of variance showed significant variation among stations （ANOVA two-way, P〈0.05）, but no significance was found between the two cruises （ANOVA two-way, P〈0.05）. Populations in stations in 500 m depth in both cruises were higher than that of 200 m depth stations with statistically insignificant difference （ANOVA two-way, P〉0.05）. Three actinomycetes genera were identified. Streptomyces was found to be the dominating one in both the cruises, followed by Micromonospora, and Actinomyces. The spore of Streptomyces isolates showed the abundance in spiral spore chain. Spore surface was smooth. Multiple regression analysis revealed that the influencing physico-chemical factors were sediment pH, sediment temperature, TOC, porosity, salinity, and pressure. The media used in the present study was prepared with seawater. Thus, they may represent an autochthonous marine flora and deny the theory of land runoff carriage into the sea for adaptation to the salinity of the seawater and sediments.
基金supported by the National Natural Science Foundation of China(No.71373089).
文摘Objective:Generic drugs provide an opportunity for savings in drug expenditure since they are available at a lower cost and do not affect patients’health.A better understanding of pharmacists’knowledge,attitudes,and perception can promote the quality use of generic drugs.The objective of this study was to investigate the knowledge,attitudes,and perception of pharmacists from tertiary hospitals in China regarding generic drugs.Methods:A cross-sectional survey using a postal questionnaire was conducted,which was sent to 200 hospital pharmacists randomly selected from tertiary hospitals in Hubei Province.A total of 125 questionnaires out of 200 were received.Of the respondents,80 were female and 45 were male.Results:The majority of respondents(87.2%)could clearly distinguish between original and generic drugs.Pharmacists agreed that generic drugs were less effective(52.8%)and produced more side effects(52%).Forty-nine respondents thought that generic drug products were not adequately tested.Approximately 78% and 60% of the pharmacists indicated that generic substitution was not feasible for drugs with narrow therapeutic windows and drugs for critical diseases,respectively.Most of them supported the recommendation of generic drugs based on professional judgment.Conclusion:Our study showed that a considerable portion of Chinese hospital pharmacists hold negative perceptions of generic drugs.Interventions to improve pharmacists'knowledge of generic drugs are needed.
基金partially supported by National Funds through FCT-"Fundacao para a Ciencia e a Tecnologia",(PEst-OE/MAT/UI0212/2011)supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry,ICT&Future Planning(No.2014R1A1A1A05002124)supported by National Natural Science Foundation of China(No.11301018 and 11371046)
文摘We prove that a Cl-generic volume-preserving dynamical system （diffeomor- phism or flow） has the shadowing property or is expansive or has the weak specification property if and only if it is Anosov. Finally, as in [10, 27], we prove that the Cl-robustness, within the volume-preserving context, of the expansiveness property and the weak specifica- tion property, imply that the dynamical system （diffeomorphism or flow） is Anosov.
基金supported by National Natural Science Foundation of China (10871133,11071246 and 11101143)Fundamental Research Funds of the Central Universities (09QL48)
文摘We use Hopf-Lax formula to study local regularity of solution to Hamilton- Jacobi （HJ） equations of multi-dimensional space variables with convex Hamiltonian. Then we give the large time generic form of the solution to HJ equation, i.e. for most initial data there exists a constant T 〉 0, which depends only on the Hamiltonian and initial datum, for t 〉 T the solution of the IVP （1.1） is smooth except for ~ smooth n-dimensional hypersurface, across which Du（x, t） is discontinuous. And we show that the hypersurface 1 tends asymptotically to a given hypersurface with rate t-1/4.
