Objective To provide suggestions for helping marketing authorization holders(MAHs)to develop an effective and compliant pharmacovigilance system.Methods The construction strategies of pharmacovigilance system of the m...Objective To provide suggestions for helping marketing authorization holders(MAHs)to develop an effective and compliant pharmacovigilance system.Methods The construction strategies of pharmacovigilance system of the multinational pharmaceutical companies were analyzed based on the requirements of regulations and laws.Results and Conclusion There are some gaps between local and multinational pharmaceutical companies in the construction of pharmacovigilance system.We can learn from the experience of multinational pharmaceutical companies to improve the pharmacovigilance system,which includes building a sound pharmacovigilance organizational structure,establishing a series of operational system files and cultivating professional talents.MAHs of China should improve the structure of enterprise pharmacovigilance system.Besides,members of Drug Safety Committee should be department managers with higher position so that they can fulfil the responsibilities of risk assessment.If MAHs possess a large variety and quantity of products,a Drug Safety Committee should be established to ensure the timely discovery of risks.In addition,MAHs should pay attention to the implementation of related regulations and laws on pharmacovigilance and establish compliant,effective and operatable files combing with the actual operation of pharmacovigilance system.Finally,MAHs should introduce and train pharmacovigilance talents,and hire pharmacovigilance experts as consultants to solve the problem of talent shortage.展开更多
Blank holder force(BHF)is a crucial parameter in deep drawing,having close relation with the forming quality of sheet metal.However,there are different BHFs maintaining the best forming effect in different stages of d...Blank holder force(BHF)is a crucial parameter in deep drawing,having close relation with the forming quality of sheet metal.However,there are different BHFs maintaining the best forming effect in different stages of deep drawing.The variable blank holder force(VBHF)varying with the drawing stage can overcome this problem at an extent.The optimization of VBHF is to determine the optimal BHF in every deep drawing stage.In this paper,a new heuristic optimization algorithm named Jaya is introduced to solve the optimization efficiently.An improved“Quasi-oppositional”strategy is added to Jaya algorithm for improving population diversity.Meanwhile,an innovated stop criterion is added for better convergence.Firstly,the quality evaluation criteria for wrinkling and tearing are built.Secondly,the Kriging models are developed to approximate and quantify the relation between VBHF and forming defects under random sampling.Finally,the optimization models are established and solved by the improved QO-Jaya algorithm.A VBHF optimization example of component with complicated shape and thin wall is studied to prove the effectiveness of the improved Jaya algorithm.The optimization results are compared with that obtained by other algorithms based on the TOPSIS method.展开更多
Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quan...Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quantum mechanics and value problems.In this paper,we first give the definition of a quasi-Cauchy type integral in complex Clifford analysis,and get the Plemelj formula for it.Second,we discuss the H?lder continuity for the Cauchy-type integral operators with values in a complex Clifford algebra.Finally,we prove the existence of solutions for a class of linear boundary value problems and give the integral representation for the solution.展开更多
Constituting the reasonable control models of the wrinkle limit blank holder forces is the sticking point of the processes of the deep drawing with variable blank-holder forces, especially in the square-box forming. T...Constituting the reasonable control models of the wrinkle limit blank holder forces is the sticking point of the processes of the deep drawing with variable blank-holder forces, especially in the square-box forming. To begin with, a mode of segmenting flange of the square-box into eight zones is put forward according to the fact that the uniformity of flange deforming can be improved by control-ling segment blank-holders. Considering the integral influence of shear stress, a new concept, strain relaxation factor is defined. Hereby, the law of distribution of stress and stain in the deforming flange of square-box is achieved. Then based on these mechanical analysis models and the energy principle, the wrinkling flexivity functions of the straight flange and the circle flange are given, and the corresponding formulae of wrinkling limit blank-holder force in these two situations are also educed. In these processes, ply-anisotropy, strain hardening, thickness and friction are considered. In the end, a calculating example is designed to validate the rationality of the formulae of wrinkling limit blank-holder force, at the same time, the influences of the ply-anisotropy exponent and the strain hardening exponent on the wrinkle limit blank holder forces are also analyzed.展开更多
The proliferation of digital payment methods facilitated by various online platforms and applications has led to a surge in financial fraud,particularly in credit card transactions.Advanced technologies such as machin...The proliferation of digital payment methods facilitated by various online platforms and applications has led to a surge in financial fraud,particularly in credit card transactions.Advanced technologies such as machine learning have been widely employed to enhance the early detection and prevention of losses arising frompotentially fraudulent activities.However,a prevalent approach in existing literature involves the use of extensive data sampling and feature selection algorithms as a precursor to subsequent investigations.While sampling techniques can significantly reduce computational time,the resulting dataset relies on generated data and the accuracy of the pre-processing machine learning models employed.Such datasets often lack true representativeness of realworld data,potentially introducing secondary issues that affect the precision of the results.For instance,undersampling may result in the loss of critical information,while over-sampling can lead to overfitting machine learning models.In this paper,we proposed a classification study of credit card fraud using fundamental machine learning models without the application of any sampling techniques on all the features present in the original dataset.The results indicate that Support Vector Machine(SVM)consistently achieves classification performance exceeding 90%across various evaluation metrics.This discovery serves as a valuable reference for future research,encouraging comparative studies on original dataset without the reliance on sampling techniques.Furthermore,we explore hybrid machine learning techniques,such as ensemble learning constructed based on SVM,K-Nearest Neighbor(KNN)and decision tree,highlighting their potential advancements in the field.The study demonstrates that the proposed machine learning models yield promising results,suggesting that pre-processing the dataset with sampling algorithm or additional machine learning technique may not always be necessary.This research contributes to the field of credit card fraud detection by emphasizing the potential of employing machine learning models directly on original datasets,thereby simplifying the workflow and potentially improving the accuracy and efficiency of fraud detection systems.展开更多
Holder’s inequality, its refinement, and reverse have received considerable attention in the theory of mathematical analysis and differential equations. In this paper, we give some refinements of Holder’s inequality...Holder’s inequality, its refinement, and reverse have received considerable attention in the theory of mathematical analysis and differential equations. In this paper, we give some refinements of Holder’s inequality and its reverse using a simple analytical technique of algebra and calculus. Our results show many results related to holder’s inequality as special cases of the inequalities presented.展开更多
This paper investigates the effects of tool holder materials on chatter vibration in turning operations.The study uses a complex dynamic turning model with two degrees of freedom for the orthogonal cutting system.Tool...This paper investigates the effects of tool holder materials on chatter vibration in turning operations.The study uses a complex dynamic turning model with two degrees of freedom for the orthogonal cutting system.Tool holders made from different materials,including Al 5083,Al 6082,Al 7012,and a standard 4140 material,were subjected to chatter vibration to investigate their process damping capabilities.The study found that the standard tool holder 4140 allows for higher stable depths of cut and produces similar process damping values compared to the other tool holders.Finite element analyses(FEA)were performed to verify the experimental results,and the modal and FEA analyses produced very similar results.The study concludes that future research should investigate the effects of tool holders made from high alloy steel alloys on process damping.Overall,this paper provides important insights into the effects of tool hold-er materials on chatter vibration and process damping in turning operations,which can help in the design of more effi-cient and effective cutting systems.展开更多
A large aspect ratio vibration reducing tool holder based on passive damping vibration reduction technology is designed to solve the vibration problem that occurs in deep hole machining of vertical lathes.A dynamic mo...A large aspect ratio vibration reducing tool holder based on passive damping vibration reduction technology is designed to solve the vibration problem that occurs in deep hole machining of vertical lathes.A dynamic model of passive damping vibration reduction tool holder was established,and the optimal damping ratio,optimal frequency ratio,and maximum relative amplitude were derived.Modal analysis of the passive damping vibrationreduction tool holder was conducted using software.The results showed that the maximum response amplitude of the passive damping vibration reduction tool holder decreased significantly compared to the original one.展开更多
The forming defects, including thinning, rupture, wrinkling and springback, usually arising in producing a side-door impact beam, were investigated by trial and numerical simulation. A temperature-related constitutive...The forming defects, including thinning, rupture, wrinkling and springback, usually arising in producing a side-door impact beam, were investigated by trial and numerical simulation. A temperature-related constitutive model specific to the temperature range from 350 °C to 500 °C was established and used for the numerical simulation. The trial and numerical simulation were conducted to clarify the quantitative characteristics of forming defects and to analyze the effects of process parameters on the forming defects. Results show that the rupture situation is ameliorated and the springback is eliminated in the aluminum alloy hot stamping. The wrinkling severity decreases with increasing blank holder force (BHF), but the BHF greater than 15 kN causes the rupture at the deepest drawing position of workpiece. The forming defects are avoided with lubricant in the feasible ranges of process parameters: the BHF of 3 to 5 kN and the stamping speed of 50 to 200 mm/s.展开更多
基金Integration Application Status and Problems Investigation of ICH Q8,Q9,Q10 across the Product Life Cycle(No.20210605).
文摘Objective To provide suggestions for helping marketing authorization holders(MAHs)to develop an effective and compliant pharmacovigilance system.Methods The construction strategies of pharmacovigilance system of the multinational pharmaceutical companies were analyzed based on the requirements of regulations and laws.Results and Conclusion There are some gaps between local and multinational pharmaceutical companies in the construction of pharmacovigilance system.We can learn from the experience of multinational pharmaceutical companies to improve the pharmacovigilance system,which includes building a sound pharmacovigilance organizational structure,establishing a series of operational system files and cultivating professional talents.MAHs of China should improve the structure of enterprise pharmacovigilance system.Besides,members of Drug Safety Committee should be department managers with higher position so that they can fulfil the responsibilities of risk assessment.If MAHs possess a large variety and quantity of products,a Drug Safety Committee should be established to ensure the timely discovery of risks.In addition,MAHs should pay attention to the implementation of related regulations and laws on pharmacovigilance and establish compliant,effective and operatable files combing with the actual operation of pharmacovigilance system.Finally,MAHs should introduce and train pharmacovigilance talents,and hire pharmacovigilance experts as consultants to solve the problem of talent shortage.
基金Supported by National Key Research and Development Program of China(Grant No.2022YFB3304200)National Natural Science Foundation of China(Grant No.52075479)Taizhou Municipal Science and Technology Project of China(Grant No.1801gy23).
文摘Blank holder force(BHF)is a crucial parameter in deep drawing,having close relation with the forming quality of sheet metal.However,there are different BHFs maintaining the best forming effect in different stages of deep drawing.The variable blank holder force(VBHF)varying with the drawing stage can overcome this problem at an extent.The optimization of VBHF is to determine the optimal BHF in every deep drawing stage.In this paper,a new heuristic optimization algorithm named Jaya is introduced to solve the optimization efficiently.An improved“Quasi-oppositional”strategy is added to Jaya algorithm for improving population diversity.Meanwhile,an innovated stop criterion is added for better convergence.Firstly,the quality evaluation criteria for wrinkling and tearing are built.Secondly,the Kriging models are developed to approximate and quantify the relation between VBHF and forming defects under random sampling.Finally,the optimization models are established and solved by the improved QO-Jaya algorithm.A VBHF optimization example of component with complicated shape and thin wall is studied to prove the effectiveness of the improved Jaya algorithm.The optimization results are compared with that obtained by other algorithms based on the TOPSIS method.
基金supported by the NSF of Hebei Province(A2022208007)the NSF of China(11571089,11871191)the NSF of Henan Province(222300420397)。
文摘Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quantum mechanics and value problems.In this paper,we first give the definition of a quasi-Cauchy type integral in complex Clifford analysis,and get the Plemelj formula for it.Second,we discuss the H?lder continuity for the Cauchy-type integral operators with values in a complex Clifford algebra.Finally,we prove the existence of solutions for a class of linear boundary value problems and give the integral representation for the solution.
文摘Constituting the reasonable control models of the wrinkle limit blank holder forces is the sticking point of the processes of the deep drawing with variable blank-holder forces, especially in the square-box forming. To begin with, a mode of segmenting flange of the square-box into eight zones is put forward according to the fact that the uniformity of flange deforming can be improved by control-ling segment blank-holders. Considering the integral influence of shear stress, a new concept, strain relaxation factor is defined. Hereby, the law of distribution of stress and stain in the deforming flange of square-box is achieved. Then based on these mechanical analysis models and the energy principle, the wrinkling flexivity functions of the straight flange and the circle flange are given, and the corresponding formulae of wrinkling limit blank-holder force in these two situations are also educed. In these processes, ply-anisotropy, strain hardening, thickness and friction are considered. In the end, a calculating example is designed to validate the rationality of the formulae of wrinkling limit blank-holder force, at the same time, the influences of the ply-anisotropy exponent and the strain hardening exponent on the wrinkle limit blank holder forces are also analyzed.
文摘The proliferation of digital payment methods facilitated by various online platforms and applications has led to a surge in financial fraud,particularly in credit card transactions.Advanced technologies such as machine learning have been widely employed to enhance the early detection and prevention of losses arising frompotentially fraudulent activities.However,a prevalent approach in existing literature involves the use of extensive data sampling and feature selection algorithms as a precursor to subsequent investigations.While sampling techniques can significantly reduce computational time,the resulting dataset relies on generated data and the accuracy of the pre-processing machine learning models employed.Such datasets often lack true representativeness of realworld data,potentially introducing secondary issues that affect the precision of the results.For instance,undersampling may result in the loss of critical information,while over-sampling can lead to overfitting machine learning models.In this paper,we proposed a classification study of credit card fraud using fundamental machine learning models without the application of any sampling techniques on all the features present in the original dataset.The results indicate that Support Vector Machine(SVM)consistently achieves classification performance exceeding 90%across various evaluation metrics.This discovery serves as a valuable reference for future research,encouraging comparative studies on original dataset without the reliance on sampling techniques.Furthermore,we explore hybrid machine learning techniques,such as ensemble learning constructed based on SVM,K-Nearest Neighbor(KNN)and decision tree,highlighting their potential advancements in the field.The study demonstrates that the proposed machine learning models yield promising results,suggesting that pre-processing the dataset with sampling algorithm or additional machine learning technique may not always be necessary.This research contributes to the field of credit card fraud detection by emphasizing the potential of employing machine learning models directly on original datasets,thereby simplifying the workflow and potentially improving the accuracy and efficiency of fraud detection systems.
文摘Holder’s inequality, its refinement, and reverse have received considerable attention in the theory of mathematical analysis and differential equations. In this paper, we give some refinements of Holder’s inequality and its reverse using a simple analytical technique of algebra and calculus. Our results show many results related to holder’s inequality as special cases of the inequalities presented.
基金This study was supported by the Scientific Research Coordination Unit of Pamukkale University under the project number 2011BSP020.
文摘This paper investigates the effects of tool holder materials on chatter vibration in turning operations.The study uses a complex dynamic turning model with two degrees of freedom for the orthogonal cutting system.Tool holders made from different materials,including Al 5083,Al 6082,Al 7012,and a standard 4140 material,were subjected to chatter vibration to investigate their process damping capabilities.The study found that the standard tool holder 4140 allows for higher stable depths of cut and produces similar process damping values compared to the other tool holders.Finite element analyses(FEA)were performed to verify the experimental results,and the modal and FEA analyses produced very similar results.The study concludes that future research should investigate the effects of tool holders made from high alloy steel alloys on process damping.Overall,this paper provides important insights into the effects of tool hold-er materials on chatter vibration and process damping in turning operations,which can help in the design of more effi-cient and effective cutting systems.
基金Science and Technology Research Project of Liaoning Provincial Department of Education:Research on the Application of Damping and Vibration Reduction Technology in Key Components of Machine Tools(JYTMS20230066)The Fund of Liaoning Provincial Natural Science and Technology Foundation Regional Joint(No.2021-YKLH-08).
文摘A large aspect ratio vibration reducing tool holder based on passive damping vibration reduction technology is designed to solve the vibration problem that occurs in deep hole machining of vertical lathes.A dynamic model of passive damping vibration reduction tool holder was established,and the optimal damping ratio,optimal frequency ratio,and maximum relative amplitude were derived.Modal analysis of the passive damping vibrationreduction tool holder was conducted using software.The results showed that the maximum response amplitude of the passive damping vibration reduction tool holder decreased significantly compared to the original one.
基金Project(P2014-15)supported by the State Key Laboratory of Materials Processing and Die&Mould Technology,Huazhong University of Science and Technology,ChinaProject supported by the Beijing Laboratory of Metallic Materials and Processing for Modern Transportation,China
文摘The forming defects, including thinning, rupture, wrinkling and springback, usually arising in producing a side-door impact beam, were investigated by trial and numerical simulation. A temperature-related constitutive model specific to the temperature range from 350 °C to 500 °C was established and used for the numerical simulation. The trial and numerical simulation were conducted to clarify the quantitative characteristics of forming defects and to analyze the effects of process parameters on the forming defects. Results show that the rupture situation is ameliorated and the springback is eliminated in the aluminum alloy hot stamping. The wrinkling severity decreases with increasing blank holder force (BHF), but the BHF greater than 15 kN causes the rupture at the deepest drawing position of workpiece. The forming defects are avoided with lubricant in the feasible ranges of process parameters: the BHF of 3 to 5 kN and the stamping speed of 50 to 200 mm/s.
