In this paper, we are concerned with output feedback stabilization for a one-dimensional anti-stable wave equation with disturbance. First, we design a disturbance estimator for the original system. Then, we propose a...In this paper, we are concerned with output feedback stabilization for a one-dimensional anti-stable wave equation with disturbance. First, we design a disturbance estimator for the original system. Then, we propose an output feedback controller for the original system. By calculation, the closed-loop of original system is proved to be exponentially stable and well-posed. Finally, this paper is summarized.展开更多
This paper has studied the output feedback regulation problem for 1-D anti-stable wave equation with distributed disturbance and a given reference signal generated by a finite-dimensional exosystem. We first design an...This paper has studied the output feedback regulation problem for 1-D anti-stable wave equation with distributed disturbance and a given reference signal generated by a finite-dimensional exosystem. We first design an observer for both exosystem and auxiliary PDE system to recover the state. Then we show the well-posedness of the regulator equations and propose an observer-based feedback control law to regulate the tracking error to zero exponentially and keep all the states bounded.展开更多
The effect of Tremella fuciformis polysaccharide(TFP)on the retrogradation property and aroma profile changes of tteok during storage was investigated.Results indicated that addition of TFP significantly increased the...The effect of Tremella fuciformis polysaccharide(TFP)on the retrogradation property and aroma profile changes of tteok during storage was investigated.Results indicated that addition of TFP significantly increased the stability to thermal and mechanical shearing of starch,decreased short-term retrogradation,the hardness and the retrogradation enthalpy(ΔH)of tteok during storage,but had no significant effect on the amylopectin chain length of tteok.The possible mechanism for the retarding staling effect of TFP is related to the interaction between TFP and starch chains that interferes with the alignment of starch chains.Electronic nose and g as chromatography-mass spectrum(GC-MS)analysis results showed that the difference in the concentrations of volatile compounds and fatty acids of tteoks at different storage time gradually increased with the advancement of storage period.The addition of TFP to tteok inhibited the development of unpleasant volatile compounds,probably by delaying the oxidation and decomposition of lipids and preserving the antioxidant phenolic compounds in tteok,thus slowing down the flavor deterioration of tteok and contributing to flavor maintainace.Overall,this study could help food manufacturers to choose a high-effective and natural polysaccharide to control the retrogradation rate and flavor loss of tteok.展开更多
The unique multi-stage dough preparation procedure using fermented glutinous rice wine(GRW)as a starter provides a cost-effective source of yeast and bacteria and produces a superior flavor in Chinese steamed bread(CS...The unique multi-stage dough preparation procedure using fermented glutinous rice wine(GRW)as a starter provides a cost-effective source of yeast and bacteria and produces a superior flavor in Chinese steamed bread(CSB).This study investigated the changes in microbial,biochemical,and physicochemical properties during the most critical mash and liquid fermentation(MLF)process and their impact on the anti-staling performance of CSB.Yeast and lactic acid bacteria proliferate within the first 12 h of fermentation,followed by the stationary and decline phases.During this period,pH and reducing sugar content decrease,while total titratable acidity(TTA)increases.Amylase and protease activities,as well as exopolysaccharide(EPS)content,reached their maximum values at 12 h of fermentation.Rheological data show that gas production and retention in the dough are maximized when MLF at a duration of 12 h,produces high-quality GRW-CSB without additional yeast.The anti-staling effect of the MLF supernatant was also evident,as the supernatant of 12-h MLF effectively slowed CSB hardness changes during storage(p<0.05),supported by shifts in starch relative crystallinity,retrogradation enthalpy,and short-range ordered structure.Correlation analysis highlighted that EPS,amylase activity,and TTA synergistically influence the anti-staling quality of CSB.展开更多
Lactobacillus amylolyticus L6,a potential probiotic rich in glycosidases like maltogenic amylase(MA),may be suitable for bread fermentation.This study investigated the texture,moisture migration,starch retrogradation,...Lactobacillus amylolyticus L6,a potential probiotic rich in glycosidases like maltogenic amylase(MA),may be suitable for bread fermentation.This study investigated the texture,moisture migration,starch retrogradation,microstructure,volatile compounds,and organoleptic properties of L6 whole-wheat sourdough bread(L6B)before and after storage at 4℃ for 7 days.Chemical acidifier whole-wheat sourdough bread(CB),commercial MA whole-wheat bread(MB),and normal whole-wheat bread(NB)were used as controls to reveal the antistaling properties and flavor characterizations.The results showed that freshly baked L6B presented the lowest hardness(362.27 g),increasing to 1449.87 g after storage,which was lower than NB(2198.94 g)and CB(1999.26 g),but higher than MB(1025.24 g).L6B consistently possessed the highest total water content(8611.67 and 7693.57 a.u.for fresh and stored bread,respectively)and bound water proportion(19.61%and 15.60%).Moreover,the retrogradation enthalpy of stored L6B(3.57 J/g)was larger than that of MB(2.54 J/g),with the lowest relative crystallinity(7.17%)and recrystallization rate(28.04%).The microstructure of dough with L6 sourdough exhibited an organized fibrous and lamellar gluten matrix,more pores,and smaller starch granules.Additionally,L6B accumulated more octanoic acid,ethyl ester,hexanoic acid,ethyl ester,and nonanal,contributing floral,fruity,and fatty flavors.Sensory evaluation indicated that L6B possessed the highest overall acceptability,being especially softer,with pleasant sourness and aroma.Overall,whole-wheat bread fermented with L6 shows promising potential,exhibiting an anti-staling capability comparable to bread with MA,enhanced organoleptic properties,and flavor.展开更多
This article focuses on the tension between the Islamic Middle East and the international community.After a brief study from the political,economic and cultural perspectives and a review of relevant documents and mate...This article focuses on the tension between the Islamic Middle East and the international community.After a brief study from the political,economic and cultural perspectives and a review of relevant documents and materials,the author has decided on the current research perspective.The sub-state actors in the Middle East mainly refer to religious and political organizations which can infiltrate into or influence this area or the international community,terrorist organizations of religious extremists,straddling groups and minority groups which seek independence or unification.Their major influence on the international community lies in their resistance against the present state weakens the nation state system in the Middle East and pushes anti-state/system movements;their significant role imposes a deep impact on the peace process in the Middle East;they lead to external intervention from the international system and growing tension between the Middle East and the international community.The root of the above-mentioned tension is that the combined actions of internal and external factors have made the Middle East system vulnerable and infiltrable,creating the soil for the rise of religious and political organizations and thus inspiring the anti-system movements of the sub-state actors in the Middle East.展开更多
文摘In this paper, we are concerned with output feedback stabilization for a one-dimensional anti-stable wave equation with disturbance. First, we design a disturbance estimator for the original system. Then, we propose an output feedback controller for the original system. By calculation, the closed-loop of original system is proved to be exponentially stable and well-posed. Finally, this paper is summarized.
文摘This paper has studied the output feedback regulation problem for 1-D anti-stable wave equation with distributed disturbance and a given reference signal generated by a finite-dimensional exosystem. We first design an observer for both exosystem and auxiliary PDE system to recover the state. Then we show the well-posedness of the regulator equations and propose an observer-based feedback control law to regulate the tracking error to zero exponentially and keep all the states bounded.
基金financially supported by the Key Projects of the National Research and Development Program of China (2018YFD0400103-6)
文摘The effect of Tremella fuciformis polysaccharide(TFP)on the retrogradation property and aroma profile changes of tteok during storage was investigated.Results indicated that addition of TFP significantly increased the stability to thermal and mechanical shearing of starch,decreased short-term retrogradation,the hardness and the retrogradation enthalpy(ΔH)of tteok during storage,but had no significant effect on the amylopectin chain length of tteok.The possible mechanism for the retarding staling effect of TFP is related to the interaction between TFP and starch chains that interferes with the alignment of starch chains.Electronic nose and g as chromatography-mass spectrum(GC-MS)analysis results showed that the difference in the concentrations of volatile compounds and fatty acids of tteoks at different storage time gradually increased with the advancement of storage period.The addition of TFP to tteok inhibited the development of unpleasant volatile compounds,probably by delaying the oxidation and decomposition of lipids and preserving the antioxidant phenolic compounds in tteok,thus slowing down the flavor deterioration of tteok and contributing to flavor maintainace.Overall,this study could help food manufacturers to choose a high-effective and natural polysaccharide to control the retrogradation rate and flavor loss of tteok.
基金supported by the National Natural Science Foundation of China(No.32101988)the Postdoctoral Research Foundation of China(No.2019 M651706)supported by the Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province,Jiangnan University.
文摘The unique multi-stage dough preparation procedure using fermented glutinous rice wine(GRW)as a starter provides a cost-effective source of yeast and bacteria and produces a superior flavor in Chinese steamed bread(CSB).This study investigated the changes in microbial,biochemical,and physicochemical properties during the most critical mash and liquid fermentation(MLF)process and their impact on the anti-staling performance of CSB.Yeast and lactic acid bacteria proliferate within the first 12 h of fermentation,followed by the stationary and decline phases.During this period,pH and reducing sugar content decrease,while total titratable acidity(TTA)increases.Amylase and protease activities,as well as exopolysaccharide(EPS)content,reached their maximum values at 12 h of fermentation.Rheological data show that gas production and retention in the dough are maximized when MLF at a duration of 12 h,produces high-quality GRW-CSB without additional yeast.The anti-staling effect of the MLF supernatant was also evident,as the supernatant of 12-h MLF effectively slowed CSB hardness changes during storage(p<0.05),supported by shifts in starch relative crystallinity,retrogradation enthalpy,and short-range ordered structure.Correlation analysis highlighted that EPS,amylase activity,and TTA synergistically influence the anti-staling quality of CSB.
基金funded by the Key-Area Research and Development Program of Guangdong Province(No.2022B0202050002).
文摘Lactobacillus amylolyticus L6,a potential probiotic rich in glycosidases like maltogenic amylase(MA),may be suitable for bread fermentation.This study investigated the texture,moisture migration,starch retrogradation,microstructure,volatile compounds,and organoleptic properties of L6 whole-wheat sourdough bread(L6B)before and after storage at 4℃ for 7 days.Chemical acidifier whole-wheat sourdough bread(CB),commercial MA whole-wheat bread(MB),and normal whole-wheat bread(NB)were used as controls to reveal the antistaling properties and flavor characterizations.The results showed that freshly baked L6B presented the lowest hardness(362.27 g),increasing to 1449.87 g after storage,which was lower than NB(2198.94 g)and CB(1999.26 g),but higher than MB(1025.24 g).L6B consistently possessed the highest total water content(8611.67 and 7693.57 a.u.for fresh and stored bread,respectively)and bound water proportion(19.61%and 15.60%).Moreover,the retrogradation enthalpy of stored L6B(3.57 J/g)was larger than that of MB(2.54 J/g),with the lowest relative crystallinity(7.17%)and recrystallization rate(28.04%).The microstructure of dough with L6 sourdough exhibited an organized fibrous and lamellar gluten matrix,more pores,and smaller starch granules.Additionally,L6B accumulated more octanoic acid,ethyl ester,hexanoic acid,ethyl ester,and nonanal,contributing floral,fruity,and fatty flavors.Sensory evaluation indicated that L6B possessed the highest overall acceptability,being especially softer,with pleasant sourness and aroma.Overall,whole-wheat bread fermented with L6 shows promising potential,exhibiting an anti-staling capability comparable to bread with MA,enhanced organoleptic properties,and flavor.
文摘This article focuses on the tension between the Islamic Middle East and the international community.After a brief study from the political,economic and cultural perspectives and a review of relevant documents and materials,the author has decided on the current research perspective.The sub-state actors in the Middle East mainly refer to religious and political organizations which can infiltrate into or influence this area or the international community,terrorist organizations of religious extremists,straddling groups and minority groups which seek independence or unification.Their major influence on the international community lies in their resistance against the present state weakens the nation state system in the Middle East and pushes anti-state/system movements;their significant role imposes a deep impact on the peace process in the Middle East;they lead to external intervention from the international system and growing tension between the Middle East and the international community.The root of the above-mentioned tension is that the combined actions of internal and external factors have made the Middle East system vulnerable and infiltrable,creating the soil for the rise of religious and political organizations and thus inspiring the anti-system movements of the sub-state actors in the Middle East.
