With the huge rise of energy demand,the power system in the current era is moving to a new standard with increased access to renewable energy sources(RESs)integrated with distribution generation(DG)network.The RESs ne...With the huge rise of energy demand,the power system in the current era is moving to a new standard with increased access to renewable energy sources(RESs)integrated with distribution generation(DG)network.The RESs necessitate interfaces for controlling the power generation.The multilevel inverter(MLI)can be exploited for RESs in two diverse modes,namely,the power generation mode(stand-alone mode),and compensator mode(statcom).Few works have been carried out in optimization of controller gains with the load variations of the single type such as reactive load variation in different cases.Nevertheless,this load type may be unbalanced hence,to overcome such issues.So,a sophisticated optimization algorithm is important.This paper aims to introduce a control design via an optimization assisted PI controller for a 7-level inverter.In the present technique,the gains of the PI controller are adjusted dynamically by the adopted hybrid scheme,grey optimizer with dragon levy update(GD-LU),based on the operating conditions of the system.Here,the gains are adjusted such that the error between the reference signal and fault signal should be minimal.Thus,better dynamic performance could be attained by the present optimized PI controller.The proposed algorithm is the combined version of grey wolf optimization(GWO)and dragonfly algorithm(DA).Finally,the performance of the proposed work is compared and validated over other state-of-the-art models concerning error measures.展开更多
With hydrophilic surface and high surface area, porous silica has been applied to load insoluble drugs. Compared to solvent equilibrium method, resveratrol(RES)–mesoporous silica microparticles(MSM) solid dispersion ...With hydrophilic surface and high surface area, porous silica has been applied to load insoluble drugs. Compared to solvent equilibrium method, resveratrol(RES)–mesoporous silica microparticles(MSM) solid dispersion prepared by fluid bed demonstrated higher drug loading and more complete dissolution. Pore volume and diameter have more remarkable effects than surface area to the drug loading and in vitro dissolution profiles. RES–polyethylene glycol solid dispersion with high drug loading showed fast but incomplete dissolution due to the recrystallization. The combination of fluid bed and MSM was an effective strategy to improve drug loading as well as dissolution for poorly water-soluble drugs.展开更多
In alkaline medium,a new flow injection chemiluminescent method has been developed for the determination of resveratrol,based on the inhibition of the chemiluminescence reaction between luminol and N-bromosuccinimide ...In alkaline medium,a new flow injection chemiluminescent method has been developed for the determination of resveratrol,based on the inhibition of the chemiluminescence reaction between luminol and N-bromosuccinimide by resveratrol.Conditions of this chemiluminescent reaction have been discussed and optimized.The linear range of determination is 6.0 10-7-1.0 10-5mg/mL for resveratrol.The detection limit is 8.15 10-8mg/mL.And the relative standard deviation（RSD）（n=11） is 0.35% for 5.0 10-6mg/mL resveratrol.The method has been applied to determine the content of resveratrol in grape skin,grape wine and traditional Chinese medicine polygonumcuspidatum seib with satisfactory results.The possible mechanism of the chemiluminescence reaction was also studied.展开更多
Classical rock mass classification systems are not applicable to carbonate rocks,especially when these are affected by karst processes.Their applications to such settings could therefore result in outcomes not represe...Classical rock mass classification systems are not applicable to carbonate rocks,especially when these are affected by karst processes.Their applications to such settings could therefore result in outcomes not representative of the real stress-strain behavior.In this study,we propose a new classification of carbonate rock masses for engineering purposes,by adapting the rock engineering system(RES) method by Hudson for fractured and karstified rock masses,in order to highlight the problems of implementation of geomechanical models to carbonate rocks.This new approach allows a less rigid classification for carbonate rock masses,taking into account the local properties of the outcrops,the site conditions and the type of engineering work as well.展开更多
This article is focused on technical and economic evaluation of more than 6-years experiences of operating the Waste Heat Recovery technology—the manner and system of flue gas processing generated in the combustion p...This article is focused on technical and economic evaluation of more than 6-years experiences of operating the Waste Heat Recovery technology—the manner and system of flue gas processing generated in the combustion process in heat & power plants, cogeneration units, etc., which burn the gaseous fuel, primarily natural gas, or methane, biogas, geothermal gas, or other gaseous mixtures containing hydrogen. The solution proposes a more effective and non-traditional use of gaseous fuel for heating, the flue gases of which are processed in order to extract additional utilisable heat, with potential elimination of CO2 from them. Deploying of the heating plant in an island regime (OFF-GRID) enables definition of the benefits brought by the 3 years of operational experience and presents visions for the future offering the possibility to utilise the support energy services at the municipal as well as regional level.展开更多
With the continuous development of information technology,data centers(DCs)consume significant and evergrowing amounts of electrical energy.Renewable energy sources(RESs)can act as clean solutions to meet this require...With the continuous development of information technology,data centers(DCs)consume significant and evergrowing amounts of electrical energy.Renewable energy sources(RESs)can act as clean solutions to meet this requirement without polluting the environment.Each DC serves numerous users for their data service demands,which are regarded as flexible loads.In this paper,the willingness to pay and time sensitivities of DC users are firstly explored,and the user-side demand response is then devised to improve the overall benefits of DC operation.Then,a Stackelberg game between a DC and its users is proposed.The upper-level model aims to maximize the profit of the DC,in which the time-varying pricing of data services is optimized,and the lower-level model addresses user’s optimal decisions for using data services while balancing their time and cost requirements.The original bi-level optimization problem is then transformed into a single-level problem using the Karush-Kuhn-Tucker optimality conditions and strong duality theory,which enables the problem to be solved efficiently.Finally,case studies are conducted to demonstrate the feasibility and effectiveness of the proposed method,as well as the effects of the time-varying data service price mechanism on the RES accommodation.展开更多
文摘With the huge rise of energy demand,the power system in the current era is moving to a new standard with increased access to renewable energy sources(RESs)integrated with distribution generation(DG)network.The RESs necessitate interfaces for controlling the power generation.The multilevel inverter(MLI)can be exploited for RESs in two diverse modes,namely,the power generation mode(stand-alone mode),and compensator mode(statcom).Few works have been carried out in optimization of controller gains with the load variations of the single type such as reactive load variation in different cases.Nevertheless,this load type may be unbalanced hence,to overcome such issues.So,a sophisticated optimization algorithm is important.This paper aims to introduce a control design via an optimization assisted PI controller for a 7-level inverter.In the present technique,the gains of the PI controller are adjusted dynamically by the adopted hybrid scheme,grey optimizer with dragon levy update(GD-LU),based on the operating conditions of the system.Here,the gains are adjusted such that the error between the reference signal and fault signal should be minimal.Thus,better dynamic performance could be attained by the present optimized PI controller.The proposed algorithm is the combined version of grey wolf optimization(GWO)and dragonfly algorithm(DA).Finally,the performance of the proposed work is compared and validated over other state-of-the-art models concerning error measures.
文摘With hydrophilic surface and high surface area, porous silica has been applied to load insoluble drugs. Compared to solvent equilibrium method, resveratrol(RES)–mesoporous silica microparticles(MSM) solid dispersion prepared by fluid bed demonstrated higher drug loading and more complete dissolution. Pore volume and diameter have more remarkable effects than surface area to the drug loading and in vitro dissolution profiles. RES–polyethylene glycol solid dispersion with high drug loading showed fast but incomplete dissolution due to the recrystallization. The combination of fluid bed and MSM was an effective strategy to improve drug loading as well as dissolution for poorly water-soluble drugs.
文摘In alkaline medium,a new flow injection chemiluminescent method has been developed for the determination of resveratrol,based on the inhibition of the chemiluminescence reaction between luminol and N-bromosuccinimide by resveratrol.Conditions of this chemiluminescent reaction have been discussed and optimized.The linear range of determination is 6.0 10-7-1.0 10-5mg/mL for resveratrol.The detection limit is 8.15 10-8mg/mL.And the relative standard deviation（RSD）（n=11） is 0.35% for 5.0 10-6mg/mL resveratrol.The method has been applied to determine the content of resveratrol in grape skin,grape wine and traditional Chinese medicine polygonumcuspidatum seib with satisfactory results.The possible mechanism of the chemiluminescence reaction was also studied.
基金supported by MIUR (Italian Ministry of Education,University and Research Grant 15034/ 2007) under Grant 2010 ex MURST 60%"Modelli geologico-tecnici, idrogeologici e geofisici per la tutela e la valorizzazione delle risorse naturali,ambientali e culturali"(coordinator G.F.Andriani) and Grant 2013 ex MURST 60%"Ricerche stratigrafico-sedimentologiche di base ed applicate per it riconoscimento,la gestione e la tutela delle georisorse e dei beni storico/culturali e geoambientali"(coordinator M.Tropeano)the project Interreg Ⅲ A-"WET SYS B" 200-2006(responsible G.F.Andriani),with the financial contribution by the European Community
文摘Classical rock mass classification systems are not applicable to carbonate rocks,especially when these are affected by karst processes.Their applications to such settings could therefore result in outcomes not representative of the real stress-strain behavior.In this study,we propose a new classification of carbonate rock masses for engineering purposes,by adapting the rock engineering system(RES) method by Hudson for fractured and karstified rock masses,in order to highlight the problems of implementation of geomechanical models to carbonate rocks.This new approach allows a less rigid classification for carbonate rock masses,taking into account the local properties of the outcrops,the site conditions and the type of engineering work as well.
文摘This article is focused on technical and economic evaluation of more than 6-years experiences of operating the Waste Heat Recovery technology—the manner and system of flue gas processing generated in the combustion process in heat & power plants, cogeneration units, etc., which burn the gaseous fuel, primarily natural gas, or methane, biogas, geothermal gas, or other gaseous mixtures containing hydrogen. The solution proposes a more effective and non-traditional use of gaseous fuel for heating, the flue gases of which are processed in order to extract additional utilisable heat, with potential elimination of CO2 from them. Deploying of the heating plant in an island regime (OFF-GRID) enables definition of the benefits brought by the 3 years of operational experience and presents visions for the future offering the possibility to utilise the support energy services at the municipal as well as regional level.
基金supported in part by National Natural Science Foundation of China(No.U1910216)in part by Science and Technology Project of State Grid Zhejiang Electric Power Co.,Ltd.(No.5211JY19000T)。
文摘With the continuous development of information technology,data centers(DCs)consume significant and evergrowing amounts of electrical energy.Renewable energy sources(RESs)can act as clean solutions to meet this requirement without polluting the environment.Each DC serves numerous users for their data service demands,which are regarded as flexible loads.In this paper,the willingness to pay and time sensitivities of DC users are firstly explored,and the user-side demand response is then devised to improve the overall benefits of DC operation.Then,a Stackelberg game between a DC and its users is proposed.The upper-level model aims to maximize the profit of the DC,in which the time-varying pricing of data services is optimized,and the lower-level model addresses user’s optimal decisions for using data services while balancing their time and cost requirements.The original bi-level optimization problem is then transformed into a single-level problem using the Karush-Kuhn-Tucker optimality conditions and strong duality theory,which enables the problem to be solved efficiently.Finally,case studies are conducted to demonstrate the feasibility and effectiveness of the proposed method,as well as the effects of the time-varying data service price mechanism on the RES accommodation.
