Day by day, the demand and popularity of denim have increased. With the increase in demand for denim, washing has also increased. When we washed a piece of denim fabric, then its properties also changed. The propertie...Day by day, the demand and popularity of denim have increased. With the increase in demand for denim, washing has also increased. When we washed a piece of denim fabric, then its properties also changed. The properties are tensile strength, GSM, color fading, stiffness, abrasion resistance, moisture regain, etc. In this study, we conduct different washing processes on denim fabric such are Stonewash, Caustic wash, Acid wash, Normal wash, Pigment wash, Sandblasting, and Super whitewash. After washing, the properties of denim fabric have been analyzed especially strength. The tear and tensile strength were measured by ISO standard. From the above washing method, Normal & pigment wash showed good strength properties comparing with others.展开更多
The wash-out filter （WF） technique is used to control the flutter of a two dimensional airfoil with cubic non-linearity in incompressible flow. Firstly, Hopf bifurcation theory is used to determine the point at whic...The wash-out filter （WF） technique is used to control the flutter of a two dimensional airfoil with cubic non-linearity in incompressible flow. Firstly, Hopf bifurcation theory is used to determine the point at which the nonlinear controller is introduced. The system is then transformed into Jordan canonical form, based on analysis of linearized eigenvalues of the system. Secondly, for the introduced WF controller, the linear control gain is determined according to Hopf bifurcation condition. The sym- bolic computing program of normal form direct method （NFDM） is also used to obtain the normal form of the controlled system. The non-linear control gain can be determined based on the relation of the type of bifurcation and the parameters of the normal form, to transform sub-critical Hopf bifurcation to be su- per-critical one. Lastly, numerical simulations are used to certify the validity of theoretical analysis, in which the amplitude of flutter or limit cycle of the controlled system is reduced greatly, comparing to the original system.展开更多
文摘Day by day, the demand and popularity of denim have increased. With the increase in demand for denim, washing has also increased. When we washed a piece of denim fabric, then its properties also changed. The properties are tensile strength, GSM, color fading, stiffness, abrasion resistance, moisture regain, etc. In this study, we conduct different washing processes on denim fabric such are Stonewash, Caustic wash, Acid wash, Normal wash, Pigment wash, Sandblasting, and Super whitewash. After washing, the properties of denim fabric have been analyzed especially strength. The tear and tensile strength were measured by ISO standard. From the above washing method, Normal & pigment wash showed good strength properties comparing with others.
文摘The wash-out filter （WF） technique is used to control the flutter of a two dimensional airfoil with cubic non-linearity in incompressible flow. Firstly, Hopf bifurcation theory is used to determine the point at which the nonlinear controller is introduced. The system is then transformed into Jordan canonical form, based on analysis of linearized eigenvalues of the system. Secondly, for the introduced WF controller, the linear control gain is determined according to Hopf bifurcation condition. The sym- bolic computing program of normal form direct method （NFDM） is also used to obtain the normal form of the controlled system. The non-linear control gain can be determined based on the relation of the type of bifurcation and the parameters of the normal form, to transform sub-critical Hopf bifurcation to be su- per-critical one. Lastly, numerical simulations are used to certify the validity of theoretical analysis, in which the amplitude of flutter or limit cycle of the controlled system is reduced greatly, comparing to the original system.
