A novel methodology is presented for simultaneously optimizing synthesis and cleaning schedule of flexible heat exchanger network(HEN)by genetic/simulated annealing algorithms(GA/SA).Through taking into account the ef...A novel methodology is presented for simultaneously optimizing synthesis and cleaning schedule of flexible heat exchanger network(HEN)by genetic/simulated annealing algorithms(GA/SA).Through taking into account the effect of fouling process on optimal network topology,a preliminary network structure possessing two-fold oversynthesis is obtained by means of pseudo-temperature enthalpy(T-H)diagram approach prior to simultaneous optimization.Thus,the computational complexity of this problem classified as NP(Non-deterministic Polynomial)-complete can be significantly reduced.The promising matches resulting from preliminary synthesis stage are further optimized in parallel with their heat exchange areas and cleaning schedule.In addition,a novel continu- ous time representation is introduced to subdivide the given time horizon into several variable-size intervals according to operating periods of heat exchangers,and then flexible HEN synthesis can be implemented in dynamic manner.A numerical example is provided to demonstrate that the presented strategy is feasible to decrease the total annual cost(TAC)and further improve network flexibility,but even more important,it may be applied to solve large-scale flexible HEN synthesis problems.展开更多
Stabilizing unstable operating points is an effective way to enhance process benefits and safety, which motivates the development for a variety of advanced control strategies. The washout filter-aided controller(WFC),...Stabilizing unstable operating points is an effective way to enhance process benefits and safety, which motivates the development for a variety of advanced control strategies. The washout filter-aided controller(WFC), originally used for electric power system and aircraft, has been introduced to adjust the dynamic behavior of chemical process. However, the parameter tuning method faces two major limitations: the dimension of operating variables must be equal to or greater than that of state variables and only one positive real eigenvalue exists in the open loop system. To overcome the two limitations, this paper proposes a new parameter tuning method, so that the WFC is applicable in most chemical processes. By solving a constrained optimization problem, the controller parameters are determined under the constraint that the reassignment of the eigenvalues of the unstable desired operating point can satisfy the stability condition. Thus parts of the equilibrium manifold including the desired operating point are stabilized without affecting the shape of the equilibrium manifold. Finally, the effectiveness of the WFC improved by the proposed parameter tuning method is illustrated through a case study for propanediol anaerobic fermentation.展开更多
The safety and antimicrobial efficacy of Ethyl lauroyl arginate HCI while using as a preservative have been introduced. Meanwhile the antimicrobial mechanism, the minimal inhibitory concentration and the stability to ...The safety and antimicrobial efficacy of Ethyl lauroyl arginate HCI while using as a preservative have been introduced. Meanwhile the antimicrobial mechanism, the minimal inhibitory concentration and the stability to heat and pH range of ethyl lauroyl arginate HCI have been introduced. The new preservatives have been developed, they are the compounds containing ethyl lauroyl arginate HCI. The high efficacy of antimicrobial of Ethyl lauroyl arginate HCI series products ha been described while added into the formulations of amino acid shampoo and toner. It has been proved that ethyl lauroyl arginate HCI series products can be the optimized option for the alternative of traditional preservatives for cosmetic products.展开更多
This study aimed at identifying the role and importance of internal control procedures for detecting and preventing money laundering operations in banks through defining the internal control procedures which contribut...This study aimed at identifying the role and importance of internal control procedures for detecting and preventing money laundering operations in banks through defining the internal control procedures which contribute to detecting money laundering operations. These procedures include the guide and policies issued by the administration of banks in order to combat laundering money operations as well as to train employees on matters pertaining to the money laundering operations. The study showed the role of the internal control procedures in detecting practically the money laundering through the automated programs and the system of saving the files and records. Furthermore, the study showed the factors affecting the internal control procedures to anti-money laundering operations. The researcher used an analytical descriptive approach for collecting data which relate to the main elements of the study, analyzing and explaining them. This study aimed at building the theoretical framework depending on audit literature which addressed internal control system, anti-money laundering systems, and control procedures of anti-money laundering. Through the theoretical framework, a questionnaire related to the application of internal control procedures and its relation to anti-money laundering operations was designed. It was distributed to the population of the study which includes internal and external auditors and the head of anti-money laundering operations unit in the Jordanian banks. The study found that applying internal control procedures is important for detecting and preventing money laundering operations in the Jordanian banks and that there are factors affecting the nature and the extent of internal control standards pertaining to anti-money laundering operations in the Jordanian banks.展开更多
基金Supported by the National Natural Science Foundation of China （20976022） and Dalian University of Technology for Constructing Interdiscipline ＇Energy＋X＇. ACKNOWLEDGEMENTS The authors gratefully acknowledge financial support from Lanzhou Petrochemical Company, PetroChina Company Limited.
文摘A novel methodology is presented for simultaneously optimizing synthesis and cleaning schedule of flexible heat exchanger network(HEN)by genetic/simulated annealing algorithms(GA/SA).Through taking into account the effect of fouling process on optimal network topology,a preliminary network structure possessing two-fold oversynthesis is obtained by means of pseudo-temperature enthalpy(T-H)diagram approach prior to simultaneous optimization.Thus,the computational complexity of this problem classified as NP(Non-deterministic Polynomial)-complete can be significantly reduced.The promising matches resulting from preliminary synthesis stage are further optimized in parallel with their heat exchange areas and cleaning schedule.In addition,a novel continu- ous time representation is introduced to subdivide the given time horizon into several variable-size intervals according to operating periods of heat exchangers,and then flexible HEN synthesis can be implemented in dynamic manner.A numerical example is provided to demonstrate that the presented strategy is feasible to decrease the total annual cost(TAC)and further improve network flexibility,but even more important,it may be applied to solve large-scale flexible HEN synthesis problems.
基金Supported by the National Basic Research Program of China(2012CB720500)the National Natural Science Foundation of China(21306100)
文摘Stabilizing unstable operating points is an effective way to enhance process benefits and safety, which motivates the development for a variety of advanced control strategies. The washout filter-aided controller(WFC), originally used for electric power system and aircraft, has been introduced to adjust the dynamic behavior of chemical process. However, the parameter tuning method faces two major limitations: the dimension of operating variables must be equal to or greater than that of state variables and only one positive real eigenvalue exists in the open loop system. To overcome the two limitations, this paper proposes a new parameter tuning method, so that the WFC is applicable in most chemical processes. By solving a constrained optimization problem, the controller parameters are determined under the constraint that the reassignment of the eigenvalues of the unstable desired operating point can satisfy the stability condition. Thus parts of the equilibrium manifold including the desired operating point are stabilized without affecting the shape of the equilibrium manifold. Finally, the effectiveness of the WFC improved by the proposed parameter tuning method is illustrated through a case study for propanediol anaerobic fermentation.
文摘The safety and antimicrobial efficacy of Ethyl lauroyl arginate HCI while using as a preservative have been introduced. Meanwhile the antimicrobial mechanism, the minimal inhibitory concentration and the stability to heat and pH range of ethyl lauroyl arginate HCI have been introduced. The new preservatives have been developed, they are the compounds containing ethyl lauroyl arginate HCI. The high efficacy of antimicrobial of Ethyl lauroyl arginate HCI series products ha been described while added into the formulations of amino acid shampoo and toner. It has been proved that ethyl lauroyl arginate HCI series products can be the optimized option for the alternative of traditional preservatives for cosmetic products.
文摘This study aimed at identifying the role and importance of internal control procedures for detecting and preventing money laundering operations in banks through defining the internal control procedures which contribute to detecting money laundering operations. These procedures include the guide and policies issued by the administration of banks in order to combat laundering money operations as well as to train employees on matters pertaining to the money laundering operations. The study showed the role of the internal control procedures in detecting practically the money laundering through the automated programs and the system of saving the files and records. Furthermore, the study showed the factors affecting the internal control procedures to anti-money laundering operations. The researcher used an analytical descriptive approach for collecting data which relate to the main elements of the study, analyzing and explaining them. This study aimed at building the theoretical framework depending on audit literature which addressed internal control system, anti-money laundering systems, and control procedures of anti-money laundering. Through the theoretical framework, a questionnaire related to the application of internal control procedures and its relation to anti-money laundering operations was designed. It was distributed to the population of the study which includes internal and external auditors and the head of anti-money laundering operations unit in the Jordanian banks. The study found that applying internal control procedures is important for detecting and preventing money laundering operations in the Jordanian banks and that there are factors affecting the nature and the extent of internal control standards pertaining to anti-money laundering operations in the Jordanian banks.
