Aiming at the industry cyber-physical system(ICPS)where Denial-of-Service(DoS)attacks and actuator failure coexist,the integrated security control problem of ICPS under multi-objective constraints was studied.First,fr...Aiming at the industry cyber-physical system(ICPS)where Denial-of-Service(DoS)attacks and actuator failure coexist,the integrated security control problem of ICPS under multi-objective constraints was studied.First,from the perspective of the defender,according to the differential impact of the system under DoS attacks of different energies,the DoS attacks energy grading detection standard was formulated,and the ICPS comprehensive security control framework was constructed.Secondly,a security transmission strategy based on event triggering was designed.Under the DoS attack energy classification detection mechanism,for large-energy attacks,the method based on time series analysis was considered to predict and compensate for lost data.Therefore,on the basis of passive and elastic response to small energy attacks,the active defense capability against DoS attacks was increased.Then by introducing the conecomplement linearization algorithm,the calculation methods of the state and fault estimation observer and the integrated safety controller were deduced,the goal of DoS attack active and passive hybrid intrusion tolerance and actuator failure active fault tolerance were realized.Finally,a simulation example of a four-capacity water tank system was given to verify the validity of the obtained conclusions.展开更多
The method of regularization factor selection determines stability and accuracy of the regularization method. A formula of regularization factor was proposed by analyzing the relationship between the improved SVD and ...The method of regularization factor selection determines stability and accuracy of the regularization method. A formula of regularization factor was proposed by analyzing the relationship between the improved SVD and regularization method. The improved SVD algorithm and regularization method could adapt to low SNR. The regularization method is better than the improved SVD in the case that SNR is below 30 and the improved SVD is better than the regularization method when SNR is higher than 30. The regularization method with the regularization factor proposed in this paper can be better applied into low SNR （5〈SNR） NMR logging. The numerical simulations and real NMR data process results indicated that the improved SVD algorithm and regularization method could adapt to the low signal to noise ratio and reduce the amount of computation greatly. These algorithms can be applied in NMR logging.展开更多
Thalictrum plants are perennial herbs in the family Ranuneulaceae, many of which are of important medicinal values. Alkaloids are major active constituents in Thalictrum plants in addition to a small amount of triterp...Thalictrum plants are perennial herbs in the family Ranuneulaceae, many of which are of important medicinal values. Alkaloids are major active constituents in Thalictrum plants in addition to a small amount of triterpene and flavonoids. The major pharmacological functions of the active constituents include： anti-tumor, anti- virus, antibiosis, antiphlogosis, hypotensive action, and etc. This paper summarizes the methods for determining the contents of chemical constituents in Thalictrum plants and new chemical constituents discovered in this genus in recent ten years.展开更多
Three steam distillation devices (D-1, D-2 and D-4) or one simultaneous distillation (D-3, water-diethyl ether) as well as the process of CO2-SFE (Supercritical fluid extraction) were adopted in extraction of essentia...Three steam distillation devices (D-1, D-2 and D-4) or one simultaneous distillation (D-3, water-diethyl ether) as well as the process of CO2-SFE (Supercritical fluid extraction) were adopted in extraction of essential oils from Chinese-fir (Cunninghamia lancedata (Lamb) Hook.) and the chemical components of the extracted essential oil were analyzed by Gas chromatograph-MS analyses. The results showed that the essential oil could be almost extracted out within 2 hours and the device-3 had the highest extraction efficiency. The major chemical component of the oil was cedrol. The yield of the extracted essential oils from Chinese fir decreased gradually with the increase of the distillation time. The best condition for extraction by means of CO2-SFE is 100 kg·cm?2 in pressure and 40°C in temperature for. Keywords Chinese fir - Essential oil - Cedrol - Supercritical fluid extraction CLC number S781.4 Document code A Foundation item: This paper was support by the Key Foundation Research Project (G1999016001) of China and the Japan International Cooperation AgencyBiography: HUANG Luo-hua (1957-), male, Research associate, Research Institute of Wood Industry, Chinese Academy of forestry, Beijing 100091, P. R. ChinaResponsible editor: Song Funan展开更多
By the optimum theory, a new cutting analytical method of the membrane structure is developed. The B-spline curve is applied to make smooth the boundary of the membrane strip. By this method, the cutting accuracy is i...By the optimum theory, a new cutting analytical method of the membrane structure is developed. The B-spline curve is applied to make smooth the boundary of the membrane strip. By this method, the cutting accuracy is improved. Finally, a cutting analysis example of a tension membrane structure is given.展开更多
In this paper, the adjoint method is applied to the statistical-dynamic model （SD-90） for the prediction of typhoon tracks along with the regularization thinking and optimal control techniques. The adjoint model and...In this paper, the adjoint method is applied to the statistical-dynamic model （SD-90） for the prediction of typhoon tracks along with the regularization thinking and optimal control techniques. The adjoint model and the gradient of objective function are deduced with the continual model respectively. For 4 typical typhoons, the forces and the initial velocity can be retrieved well, and the tracks of these typhoons are accurately fitted for an appropriate regularization parameter and optimal control parameter.展开更多
Aim To study the dIelectric breakdown phenomenon in the materials with quenched disorder. Methods Renormolization group methods were used. Results The percolation limit for breakdown pc , the breakdown field Ec～(Pc-...Aim To study the dIelectric breakdown phenomenon in the materials with quenched disorder. Methods Renormolization group methods were used. Results The percolation limit for breakdown pc , the breakdown field Ec～(Pc-p)v, and the fractal dimension of the structure of dielectric breakdown df were obtained. Conclusion The breakdown properties of the materials with quenched disorder are characterized by universal power laws, where the exponents are universal.展开更多
基金supported by Gansu Higher Education Innovation Fund Project(No.2023B-439)。
文摘Aiming at the industry cyber-physical system(ICPS)where Denial-of-Service(DoS)attacks and actuator failure coexist,the integrated security control problem of ICPS under multi-objective constraints was studied.First,from the perspective of the defender,according to the differential impact of the system under DoS attacks of different energies,the DoS attacks energy grading detection standard was formulated,and the ICPS comprehensive security control framework was constructed.Secondly,a security transmission strategy based on event triggering was designed.Under the DoS attack energy classification detection mechanism,for large-energy attacks,the method based on time series analysis was considered to predict and compensate for lost data.Therefore,on the basis of passive and elastic response to small energy attacks,the active defense capability against DoS attacks was increased.Then by introducing the conecomplement linearization algorithm,the calculation methods of the state and fault estimation observer and the integrated safety controller were deduced,the goal of DoS attack active and passive hybrid intrusion tolerance and actuator failure active fault tolerance were realized.Finally,a simulation example of a four-capacity water tank system was given to verify the validity of the obtained conclusions.
文摘The method of regularization factor selection determines stability and accuracy of the regularization method. A formula of regularization factor was proposed by analyzing the relationship between the improved SVD and regularization method. The improved SVD algorithm and regularization method could adapt to low SNR. The regularization method is better than the improved SVD in the case that SNR is below 30 and the improved SVD is better than the regularization method when SNR is higher than 30. The regularization method with the regularization factor proposed in this paper can be better applied into low SNR （5〈SNR） NMR logging. The numerical simulations and real NMR data process results indicated that the improved SVD algorithm and regularization method could adapt to the low signal to noise ratio and reduce the amount of computation greatly. These algorithms can be applied in NMR logging.
基金Supported by the State Key Development Program for Basic Research of ChinaScientific and Technological Development Project of Shandong Province(2008GG2NS02022)~~
文摘Thalictrum plants are perennial herbs in the family Ranuneulaceae, many of which are of important medicinal values. Alkaloids are major active constituents in Thalictrum plants in addition to a small amount of triterpene and flavonoids. The major pharmacological functions of the active constituents include： anti-tumor, anti- virus, antibiosis, antiphlogosis, hypotensive action, and etc. This paper summarizes the methods for determining the contents of chemical constituents in Thalictrum plants and new chemical constituents discovered in this genus in recent ten years.
基金The Key Foundation Research Project (G1999016001) of China and the Japan International Cooperation Agency
文摘Three steam distillation devices (D-1, D-2 and D-4) or one simultaneous distillation (D-3, water-diethyl ether) as well as the process of CO2-SFE (Supercritical fluid extraction) were adopted in extraction of essential oils from Chinese-fir (Cunninghamia lancedata (Lamb) Hook.) and the chemical components of the extracted essential oil were analyzed by Gas chromatograph-MS analyses. The results showed that the essential oil could be almost extracted out within 2 hours and the device-3 had the highest extraction efficiency. The major chemical component of the oil was cedrol. The yield of the extracted essential oils from Chinese fir decreased gradually with the increase of the distillation time. The best condition for extraction by means of CO2-SFE is 100 kg·cm?2 in pressure and 40°C in temperature for. Keywords Chinese fir - Essential oil - Cedrol - Supercritical fluid extraction CLC number S781.4 Document code A Foundation item: This paper was support by the Key Foundation Research Project (G1999016001) of China and the Japan International Cooperation AgencyBiography: HUANG Luo-hua (1957-), male, Research associate, Research Institute of Wood Industry, Chinese Academy of forestry, Beijing 100091, P. R. ChinaResponsible editor: Song Funan
文摘By the optimum theory, a new cutting analytical method of the membrane structure is developed. The B-spline curve is applied to make smooth the boundary of the membrane strip. By this method, the cutting accuracy is improved. Finally, a cutting analysis example of a tension membrane structure is given.
基金The National Nature Science Foundation of China under Grant No.90411006 supported this work simultaneously.
文摘In this paper, the adjoint method is applied to the statistical-dynamic model （SD-90） for the prediction of typhoon tracks along with the regularization thinking and optimal control techniques. The adjoint model and the gradient of objective function are deduced with the continual model respectively. For 4 typical typhoons, the forces and the initial velocity can be retrieved well, and the tracks of these typhoons are accurately fitted for an appropriate regularization parameter and optimal control parameter.
文摘Aim To study the dIelectric breakdown phenomenon in the materials with quenched disorder. Methods Renormolization group methods were used. Results The percolation limit for breakdown pc , the breakdown field Ec～(Pc-p)v, and the fractal dimension of the structure of dielectric breakdown df were obtained. Conclusion The breakdown properties of the materials with quenched disorder are characterized by universal power laws, where the exponents are universal.
