Planting plant such as Betung bamboo (Dendrocalamus asper (Schult f.) Backer ex Heyne) is one of the best ways for reducing global warming effect. Betung bamboo is giant grass (Poaceae) which has been traditiona...Planting plant such as Betung bamboo (Dendrocalamus asper (Schult f.) Backer ex Heyne) is one of the best ways for reducing global warming effect. Betung bamboo is giant grass (Poaceae) which has been traditionally used by Indonesian people for construction material since a long time ago. Poaceae family commonly has better carbon sink ability than trees because of its Ca photosynthesis mechanisms, but bamboo sub-family (Bambusoideae) lacks the Ca photosynthetic pathway and anatomy. In the absence of this feature the maximum possible productivity of bamboos is unlikely to greatly exceed that of other bioenergy crops with C3 photosynthesis such as fast growing tree species. This research proposed a sinusoidal equation as a basic equation for plant's daily photosynthesis light response curve fitting. The sinusoidal equation was success for Betung bamboo's daily photosynthesis light response curve fitting (R2 〉 60%). It had similar result in estimating carbon sink (82.35 kg/clump/year) compared to those which calculated by annual increment (69.01-107.82 kg/clump/year). It is better to choose sinusoidal equation than quadratic or cubic Betung bamboo is a good choice to be planted in order to resist the global warming effect because it has superior carbon sink capability (82.35 kg/clump/year) than slow growing tree, and equal to fast growing tree species, besides many other advantages.展开更多
An effective and simple way to develop equations from impact strain signals was proposed.Little research has been performed in this area,but this equation is very important for evaluating input signals in finite eleme...An effective and simple way to develop equations from impact strain signals was proposed.Little research has been performed in this area,but this equation is very important for evaluating input signals in finite element analysis impact tests and for obtaining additional information on material deformation and fracture processes under impact loading.For this purpose,dynamic impact responses were examined through signals obtained from a strain gauge installed on an impact striker connected to a data acquisition system.Aluminium 6061-T6 was used to extract strain responses on the striker during Charpy impact testing.Statistical analysis was performed using the I-kaz method,and curve fitting equations based on the equation for vibration response under a non-periodic force were used to evaluate the Charpy impact signals.The I-kaz coefficients and curve fitting equations were then compared and discussed with related parameters,such as velocities and thicknesses.Velocity and thickness were found to be related to the strain signal patterns,curve fitting equations and I-kaz coefficients.The equations developed using this method had R2 values greater than 97.7%.Finally,the constructed equations were determined to be suitable for evaluating Charpy impact strain signal patterns and obtaining additional information on fracture processes under impact loading.展开更多
The paper considers a scalar linear differential difference equation (LDDE) of mixed type x(t) = (a0 + a1t)X(t) + (b0 + b1t)x(t - 1) + (d0 + d1tx(t + 1) + f(t), t ∈ R, (*) where f(t) = ∑...The paper considers a scalar linear differential difference equation (LDDE) of mixed type x(t) = (a0 + a1t)X(t) + (b0 + b1t)x(t - 1) + (d0 + d1tx(t + 1) + f(t), t ∈ R, (*) where f(t) = ∑n=0^F fn^tn. This equation is investigated with the use of the method of polynomial quasisolutions based on the representation of an unknown function in the form of polynomial x(t) = ∑n=0^N xn^tn. As a result of substitution of this function into equation (*), there appears a residual △(t) = 0(t^N), for which an exact analytical representation has been obtained. In turn, this allows one to find the unknown coefficients xn and consequently the polynomial quasisolution x(t). Several examples are considered.展开更多
文摘Planting plant such as Betung bamboo (Dendrocalamus asper (Schult f.) Backer ex Heyne) is one of the best ways for reducing global warming effect. Betung bamboo is giant grass (Poaceae) which has been traditionally used by Indonesian people for construction material since a long time ago. Poaceae family commonly has better carbon sink ability than trees because of its Ca photosynthesis mechanisms, but bamboo sub-family (Bambusoideae) lacks the Ca photosynthetic pathway and anatomy. In the absence of this feature the maximum possible productivity of bamboos is unlikely to greatly exceed that of other bioenergy crops with C3 photosynthesis such as fast growing tree species. This research proposed a sinusoidal equation as a basic equation for plant's daily photosynthesis light response curve fitting. The sinusoidal equation was success for Betung bamboo's daily photosynthesis light response curve fitting (R2 〉 60%). It had similar result in estimating carbon sink (82.35 kg/clump/year) compared to those which calculated by annual increment (69.01-107.82 kg/clump/year). It is better to choose sinusoidal equation than quadratic or cubic Betung bamboo is a good choice to be planted in order to resist the global warming effect because it has superior carbon sink capability (82.35 kg/clump/year) than slow growing tree, and equal to fast growing tree species, besides many other advantages.
基金Universiti Kebangsaan Malaysia grant UKM-KK-03-FRGS 0118-2010Universiti Teknikal Malaysia Melaka for supporting these research activities
文摘An effective and simple way to develop equations from impact strain signals was proposed.Little research has been performed in this area,but this equation is very important for evaluating input signals in finite element analysis impact tests and for obtaining additional information on material deformation and fracture processes under impact loading.For this purpose,dynamic impact responses were examined through signals obtained from a strain gauge installed on an impact striker connected to a data acquisition system.Aluminium 6061-T6 was used to extract strain responses on the striker during Charpy impact testing.Statistical analysis was performed using the I-kaz method,and curve fitting equations based on the equation for vibration response under a non-periodic force were used to evaluate the Charpy impact signals.The I-kaz coefficients and curve fitting equations were then compared and discussed with related parameters,such as velocities and thicknesses.Velocity and thickness were found to be related to the strain signal patterns,curve fitting equations and I-kaz coefficients.The equations developed using this method had R2 values greater than 97.7%.Finally,the constructed equations were determined to be suitable for evaluating Charpy impact strain signal patterns and obtaining additional information on fracture processes under impact loading.
文摘The paper considers a scalar linear differential difference equation (LDDE) of mixed type x(t) = (a0 + a1t)X(t) + (b0 + b1t)x(t - 1) + (d0 + d1tx(t + 1) + f(t), t ∈ R, (*) where f(t) = ∑n=0^F fn^tn. This equation is investigated with the use of the method of polynomial quasisolutions based on the representation of an unknown function in the form of polynomial x(t) = ∑n=0^N xn^tn. As a result of substitution of this function into equation (*), there appears a residual △(t) = 0(t^N), for which an exact analytical representation has been obtained. In turn, this allows one to find the unknown coefficients xn and consequently the polynomial quasisolution x(t). Several examples are considered.