Agarases are hydrolytic enzymes that act on the hydrolysis of agar and have a broad range of applications in food,cosmetics and pharmaceutical industries. In this study, a glycerol feeding strategy based on induction ...Agarases are hydrolytic enzymes that act on the hydrolysis of agar and have a broad range of applications in food,cosmetics and pharmaceutical industries. In this study, a glycerol feeding strategy based on induction mode optimization for high cell density and β-agarase production was established, which could effectively control acetate yield. First, exponential feeding strategy of glycerol with different overall specific growth rates（μ） was applied in the pre-induction phase. The results showed that the low μ（μ=0.2） was suggested to be the optimal for cell growth and β-agarase production. Second, the effects of induction temperature and the inducer concentration on cell growth and β-agarase production were investigated in the post-induction phase. When induced by isopropyl-β-d-thiogalactoside（IPTG）, the strategy of 0.8 mmol/L IPTG induction at 20℃ was found to be optimal for β-agarase production. When cultivation was induced by continuous lactose feeding strategy of 1.0 g/（L·h）, the β-agarase activity reached 112.5 U/mL, which represented the highest β-agarase production to date.Furthermore, the β-agarase was capable of degrading G. lemaneiformis powder directly to produce neoagarooligosaccharide, and the hydrolysates were neoagarotetraose（NA4） and neoagarohexaose（NA6）. The overall research may be useful for the industrial production and application of β-agarase.展开更多
Cracking furnace is the core device for ethylene production. In practice, multiple ethylene furnaces are usually run in parallel. The scheduling of the entire cracking furnace system has great significance when multip...Cracking furnace is the core device for ethylene production. In practice, multiple ethylene furnaces are usually run in parallel. The scheduling of the entire cracking furnace system has great significance when multiple feeds are simultaneously processed in multiple cracking furnaces with the changing of operating cost and yield of product. In this paper, given the requirements of both profit and energy saving in actual production process, a multi-objective optimization model contains two objectives, maximizing the average benefits and minimizing the average coking amount was proposed. The model can be abstracted as a multi-objective mixed integer non- linear programming problem. Considering the mixed integer decision variables of this multi-objective problem, an improved hybrid encoding non-dominated sorting genetic algorithm with mixed discrete variables （MDNSGA-II） is used to solve the Pareto optimal front of this model, the algorithm adopted crossover and muta- tion strategy with multi-operators, which overcomes the deficiency that normal genetic algorithm cannot handle the optimization problem with mixed variables. Finally, using an ethylene plant with multiple cracking furnaces as an example to illustrate the effectiveness of the scheduling results by comparing the optimization results of multi-objective and single objective model.展开更多
Optimal glucose feed strategy for glycerol fed-batch fermentation was investigated by Pontryagin’s maximum principle to maximize the final glycerol yield. The problem was solved by a nonsingular control approach by s...Optimal glucose feed strategy for glycerol fed-batch fermentation was investigated by Pontryagin’s maximum principle to maximize the final glycerol yield. The problem was solved by a nonsingular control approach by selecting the culture volume as the control variable, then the general optimal feed profile was numerically determined.展开更多
The integration of artificial intelligence(AI)in aquaculture has been identified as a transformative force,enhancing various operational aspects from water quality management to genetic optimization.This review provid...The integration of artificial intelligence(AI)in aquaculture has been identified as a transformative force,enhancing various operational aspects from water quality management to genetic optimization.This review provides a comprehensive synthesis of recent advancements in AI applications within the aquaculture sector,underscoring the significant enhancements in production efficiency and environmental sustainability.Key AI-driven improvements,such as predictive analytics for disease management and optimized feeding protocols,are highlighted,demonstrating their contributions to reducing waste and improving biomass outputs.However,challenges remain in terms of data quality,system integration,and the socio-economic impacts of technological adoption across diverse aquacultural environments.This review also addresses the gaps in current research,particularly the lack of robust,scalable AI models and frameworks that can be universally applied.Future directions are discussed,emphasizing the need for interdisciplinary research and development to fully leverage AI potential in aquaculture.This study not only maps the current landscape of AI applications but also serves as a call for continued innovation and strategic collaborations to overcome existing barriers and realize the full benefits of AI in aquaculture.展开更多
The active multi-beam antenna can be widely used in the 6G integrated satellite network project,the national satellite Internet project,and other major satellite projects.It determines the key performance indicators o...The active multi-beam antenna can be widely used in the 6G integrated satellite network project,the national satellite Internet project,and other major satellite projects.It determines the key performance indicators of the satellite such as the service coverage area and the communication capacity of all the beams in the forward link and the return link.The active multi-beam antenna is the core technology of satellite payload and has been developed rapidly in recent years.Based on the antenna performance requirements such as the number of giant-scale beams,super-large coverage area,high gain,and high carrier-to-interference ratio(C/I),this paper proposes a new active multi-beam antenna design method,which integrates the multi-objective coordination and multi-feed amplitude and phase weighted optimization algorithms.A balanced optimal solution that meets the performance requirements can be obtained by constraining each other with different objective functions.In the optimization process,the surrogate model of convolutional autoencoder based on artificial intelligence technology is proposed for multi-objective optimization solution,which efficiently completes the search of optimal beam excitation coefficients.This paper takes the demand for very-high-throughput communication satellites serving the Asia-Pacific region as an example and applies the design method to the multi-beam antenna design of the satellite.The simulation verification of the antenna is completed,achieving good performance of 976 beams.All results meet the performance requirements,supporting the implementation of 1 Tbps communication capacity for the entire satellite,and verifying the correctness of the design method.展开更多
基金The Public Science and Technology Research Funds Projects of Ocean under contract No.201505026the Fujian Province Natural Science Foundation under contract Nos 2016J01160 and 2017N0015the Scientific Research Foundation of Third Institute of Oceanography,SOA under contract No.2016038
文摘Agarases are hydrolytic enzymes that act on the hydrolysis of agar and have a broad range of applications in food,cosmetics and pharmaceutical industries. In this study, a glycerol feeding strategy based on induction mode optimization for high cell density and β-agarase production was established, which could effectively control acetate yield. First, exponential feeding strategy of glycerol with different overall specific growth rates（μ） was applied in the pre-induction phase. The results showed that the low μ（μ=0.2） was suggested to be the optimal for cell growth and β-agarase production. Second, the effects of induction temperature and the inducer concentration on cell growth and β-agarase production were investigated in the post-induction phase. When induced by isopropyl-β-d-thiogalactoside（IPTG）, the strategy of 0.8 mmol/L IPTG induction at 20℃ was found to be optimal for β-agarase production. When cultivation was induced by continuous lactose feeding strategy of 1.0 g/（L·h）, the β-agarase activity reached 112.5 U/mL, which represented the highest β-agarase production to date.Furthermore, the β-agarase was capable of degrading G. lemaneiformis powder directly to produce neoagarooligosaccharide, and the hydrolysates were neoagarotetraose（NA4） and neoagarohexaose（NA6）. The overall research may be useful for the industrial production and application of β-agarase.
基金Supported by the National Natural Science Foundation of China(21276078)"Shu Guang"project of Shanghai Municipal Education Commission,973 Program of China(2012CB720500)the Shanghai Science and Technology Program(13QH1401200)
文摘Cracking furnace is the core device for ethylene production. In practice, multiple ethylene furnaces are usually run in parallel. The scheduling of the entire cracking furnace system has great significance when multiple feeds are simultaneously processed in multiple cracking furnaces with the changing of operating cost and yield of product. In this paper, given the requirements of both profit and energy saving in actual production process, a multi-objective optimization model contains two objectives, maximizing the average benefits and minimizing the average coking amount was proposed. The model can be abstracted as a multi-objective mixed integer non- linear programming problem. Considering the mixed integer decision variables of this multi-objective problem, an improved hybrid encoding non-dominated sorting genetic algorithm with mixed discrete variables （MDNSGA-II） is used to solve the Pareto optimal front of this model, the algorithm adopted crossover and muta- tion strategy with multi-operators, which overcomes the deficiency that normal genetic algorithm cannot handle the optimization problem with mixed variables. Finally, using an ethylene plant with multiple cracking furnaces as an example to illustrate the effectiveness of the scheduling results by comparing the optimization results of multi-objective and single objective model.
基金From National Ninth Five Years Project (NO. 96-03-03-03A).
文摘Optimal glucose feed strategy for glycerol fed-batch fermentation was investigated by Pontryagin’s maximum principle to maximize the final glycerol yield. The problem was solved by a nonsingular control approach by selecting the culture volume as the control variable, then the general optimal feed profile was numerically determined.
基金funding sources,including the National Natural Science Foundation of China(No.51709254,No.32201384)Youth Innovation Promotion Association,Chinese Academy of Sciences(No.2020335)+1 种基金Key Research and Development Program of Hubei Province,China(2020BCA073)National Science&Technology Fundamental Resources Investigation Program of China(2019FY100602).
文摘The integration of artificial intelligence(AI)in aquaculture has been identified as a transformative force,enhancing various operational aspects from water quality management to genetic optimization.This review provides a comprehensive synthesis of recent advancements in AI applications within the aquaculture sector,underscoring the significant enhancements in production efficiency and environmental sustainability.Key AI-driven improvements,such as predictive analytics for disease management and optimized feeding protocols,are highlighted,demonstrating their contributions to reducing waste and improving biomass outputs.However,challenges remain in terms of data quality,system integration,and the socio-economic impacts of technological adoption across diverse aquacultural environments.This review also addresses the gaps in current research,particularly the lack of robust,scalable AI models and frameworks that can be universally applied.Future directions are discussed,emphasizing the need for interdisciplinary research and development to fully leverage AI potential in aquaculture.This study not only maps the current landscape of AI applications but also serves as a call for continued innovation and strategic collaborations to overcome existing barriers and realize the full benefits of AI in aquaculture.
基金supported by the Fund from the National Natural Science Foundation of China(Grant No.62271387)a pre-research project on Civil Aerospace Technologies(Grant No.D010203).
文摘The active multi-beam antenna can be widely used in the 6G integrated satellite network project,the national satellite Internet project,and other major satellite projects.It determines the key performance indicators of the satellite such as the service coverage area and the communication capacity of all the beams in the forward link and the return link.The active multi-beam antenna is the core technology of satellite payload and has been developed rapidly in recent years.Based on the antenna performance requirements such as the number of giant-scale beams,super-large coverage area,high gain,and high carrier-to-interference ratio(C/I),this paper proposes a new active multi-beam antenna design method,which integrates the multi-objective coordination and multi-feed amplitude and phase weighted optimization algorithms.A balanced optimal solution that meets the performance requirements can be obtained by constraining each other with different objective functions.In the optimization process,the surrogate model of convolutional autoencoder based on artificial intelligence technology is proposed for multi-objective optimization solution,which efficiently completes the search of optimal beam excitation coefficients.This paper takes the demand for very-high-throughput communication satellites serving the Asia-Pacific region as an example and applies the design method to the multi-beam antenna design of the satellite.The simulation verification of the antenna is completed,achieving good performance of 976 beams.All results meet the performance requirements,supporting the implementation of 1 Tbps communication capacity for the entire satellite,and verifying the correctness of the design method.
