High-quality fragrant rice Daohuaxiang 2 is a well-known variety in grain industry of Heilongjiang Province. However, its fragrance has weakened in recent years. In this paper, the causes for fragrance diminishing of ...High-quality fragrant rice Daohuaxiang 2 is a well-known variety in grain industry of Heilongjiang Province. However, its fragrance has weakened in recent years. In this paper, the causes for fragrance diminishing of Daohuaxiang 2 were discussed in depth. It was pointed out that variety degeneration, growth period influence, environmental factor influence, soil fertility influence and long drying time were the main causes for fragrance diminishing of Daohuaxiang 2. In addition, countermeasures for avoiding the fragrance diminishing were put forward.展开更多
The robustness analysis problem of a class of nonlinear descriptor systems is studied. Nonlinear matrix inequality which has the good computation property of convex feasibility is employed to derive some sufficient co...The robustness analysis problem of a class of nonlinear descriptor systems is studied. Nonlinear matrix inequality which has the good computation property of convex feasibility is employed to derive some sufficient conditions to guarantee that the nonlinear descriptor systems have robust disturbance attenuation performance, which (avoids) the computational difficulties in conversing nonlinear matrix and Hamilton-Jacobi inequality. The computation property of convex feasibility of nonlinear matrix inequality makes it possible to apply the results of nonlinear robust control to practice.展开更多
Effect of fluid elasticity and shear-thinning viscosity on the chaotic mixing between two alternately rotating cylinders has been studied. The h-p finite element method is used to obtain high accurate solutions of the...Effect of fluid elasticity and shear-thinning viscosity on the chaotic mixing between two alternately rotating cylinders has been studied. The h-p finite element method is used to obtain high accurate solutions of the steady flow. The unsteady, periodic flow is simulated using the piecewise-steady approximation. Characteristics of the chaotic mixing are analyzed by examining the asymptotic coverage of a passive tracer and the lineal stretching of the fluid elements in the annulus. For the viscoelastic fluids modeled by the upper-convected Maxwell constitutive equation (UCM), our computation predicts little effect of the fluid elasticity on the mixing patterns. On the other hand, the shear-thinning viscosity, modeled by the Carreau equation, has a large impact on the advection of a passive tracer and the distribution of lineal stretching. We find that the zones of the lowest stretching match remarkably well with the regular zones in the tracer-coverage plotting. Our study reveals the vital importance of reducing the discretization errors of the velocity field in the numerical simulation of chaotic flews.展开更多
The exact solutions of a new coupled Burgers system are studied in three different ways. The first type of solutions are found thanks to the coupled Burgers system possessing a simple single Burgers reduction. The sec...The exact solutions of a new coupled Burgers system are studied in three different ways. The first type of solutions are found thanks to the coupled Burgers system possessing a simple single Burgers reduction. The second type of multiple soliton solutions are revealed via the decouple procedure. The third type of exact solutions are found by means of a prior ansatz and solutions of the heat conduction equation. Two different kinds of soliton fission phenomena of the model are discovered and a special type of completely elastic soliton collision without phase shift of the model is also displayed.展开更多
The flux-weakening performance of a permanent magnet brushless AC drive was investigated using both floating-point and fixed-point DSP controllers. A significant current oscillation was observed when the drive was ope...The flux-weakening performance of a permanent magnet brushless AC drive was investigated using both floating-point and fixed-point DSP controllers. A significant current oscillation was observed when the drive was operated at high-speed in the flux-weakening mode with the fixed-point DSP. The investigation showed that this was due to the on-line compensation of the winding resistance voltage drop and quantisation errors associated with the fixed-point architecture of the DSP. A simple look-up table scheme is proposed to eliminate the oscillation and to achieve extended flux-weakening capability.展开更多
Methamidophos resistance of brown planthopper ( Nilaparvata lugens Stl, BPH) was selected in laboratory. After successive selection for 9 generations, the selection was ceased by rearing BPH without contact with an...Methamidophos resistance of brown planthopper ( Nilaparvata lugens Stl, BPH) was selected in laboratory. After successive selection for 9 generations, the selection was ceased by rearing BPH without contact with any insecticide for 9 generations. In the full course, the successive changes of esterase activity, MFO activity, GSTs activity and AChE insensitivity were analyzed. The results showed that the change of esterase activity was high correlated with that of methamidophos in the full course, which indicated that esterase played very important role both in the resistance development and in the resistance decline. However, the change of AChE insensitivity only significantly correlated with that of resistance in the development stage, and the change of MFO activity or GSTs activity only significantly correlated with that of the resistance in the decline stage, which indicated the changes of AChE insensitivity, MFO activity or GSTs activity only played some roles in different stages of the resistance change.展开更多
Cirrhosis is associated with debilitating complications that significantly impact on a patient’s physical function and reduce quality of life.Owing to highly prevalent sarcopenia,malnutrition and hepatic encephalopat...Cirrhosis is associated with debilitating complications that significantly impact on a patient’s physical function and reduce quality of life.Owing to highly prevalent sarcopenia,malnutrition and hepatic encephalopathy,functional impairment or frailty is a common complication of cirrhosis.Frailty in turn increases the patient’s risk of hospitalization,accidental falls and fractures,and death.The management of frailty and its associated adverse effects is imperative in improving the overall prognosis of patients with advanced liver disease.The cornerstone of therapy revolves around optimizing physical function with appropriate nutrition and exercise.Nutritional therapy with protein supplementation has shown significant benefit,while studies on exercise have been controversial.However,newly emerging studies trend towards a beneficial effect of physical exercise with improvement in quality of life.The implementation of technology in liver disease management shows future promise.Fitbits and other wearable devices can be used to help monitor a patient’s personal progress in physical exercise and nutritional optimization.Additionally,the progressive development of new smartphone applications to help aid in the diagnosis and monitoring of complications of cirrhosis provides a sophisticated avenue for improving care of patients with cirrhosis.展开更多
文摘High-quality fragrant rice Daohuaxiang 2 is a well-known variety in grain industry of Heilongjiang Province. However, its fragrance has weakened in recent years. In this paper, the causes for fragrance diminishing of Daohuaxiang 2 were discussed in depth. It was pointed out that variety degeneration, growth period influence, environmental factor influence, soil fertility influence and long drying time were the main causes for fragrance diminishing of Daohuaxiang 2. In addition, countermeasures for avoiding the fragrance diminishing were put forward.
基金ProjectsupportedbytheTeachingandResearchAwardProgramforOutstandingYoungTeachersinHigherEducationInstitutionsofMOE China
文摘The robustness analysis problem of a class of nonlinear descriptor systems is studied. Nonlinear matrix inequality which has the good computation property of convex feasibility is employed to derive some sufficient conditions to guarantee that the nonlinear descriptor systems have robust disturbance attenuation performance, which (avoids) the computational difficulties in conversing nonlinear matrix and Hamilton-Jacobi inequality. The computation property of convex feasibility of nonlinear matrix inequality makes it possible to apply the results of nonlinear robust control to practice.
基金Supported by the National Natural Science Foundation of China (No. 29776039), Skloche PRE Laboratory of China and Cao Guangbiao Science Foundation of Zhejiang University.
文摘Effect of fluid elasticity and shear-thinning viscosity on the chaotic mixing between two alternately rotating cylinders has been studied. The h-p finite element method is used to obtain high accurate solutions of the steady flow. The unsteady, periodic flow is simulated using the piecewise-steady approximation. Characteristics of the chaotic mixing are analyzed by examining the asymptotic coverage of a passive tracer and the lineal stretching of the fluid elements in the annulus. For the viscoelastic fluids modeled by the upper-convected Maxwell constitutive equation (UCM), our computation predicts little effect of the fluid elasticity on the mixing patterns. On the other hand, the shear-thinning viscosity, modeled by the Carreau equation, has a large impact on the advection of a passive tracer and the distribution of lineal stretching. We find that the zones of the lowest stretching match remarkably well with the regular zones in the tracer-coverage plotting. Our study reveals the vital importance of reducing the discretization errors of the velocity field in the numerical simulation of chaotic flews.
基金The author is indebt to Prof. S.Y. Lou for his helpful discussions.
文摘The exact solutions of a new coupled Burgers system are studied in three different ways. The first type of solutions are found thanks to the coupled Burgers system possessing a simple single Burgers reduction. The second type of multiple soliton solutions are revealed via the decouple procedure. The third type of exact solutions are found by means of a prior ansatz and solutions of the heat conduction equation. Two different kinds of soliton fission phenomena of the model are discovered and a special type of completely elastic soliton collision without phase shift of the model is also displayed.
文摘The flux-weakening performance of a permanent magnet brushless AC drive was investigated using both floating-point and fixed-point DSP controllers. A significant current oscillation was observed when the drive was operated at high-speed in the flux-weakening mode with the fixed-point DSP. The investigation showed that this was due to the on-line compensation of the winding resistance voltage drop and quantisation errors associated with the fixed-point architecture of the DSP. A simple look-up table scheme is proposed to eliminate the oscillation and to achieve extended flux-weakening capability.
文摘Methamidophos resistance of brown planthopper ( Nilaparvata lugens Stl, BPH) was selected in laboratory. After successive selection for 9 generations, the selection was ceased by rearing BPH without contact with any insecticide for 9 generations. In the full course, the successive changes of esterase activity, MFO activity, GSTs activity and AChE insensitivity were analyzed. The results showed that the change of esterase activity was high correlated with that of methamidophos in the full course, which indicated that esterase played very important role both in the resistance development and in the resistance decline. However, the change of AChE insensitivity only significantly correlated with that of resistance in the development stage, and the change of MFO activity or GSTs activity only significantly correlated with that of the resistance in the decline stage, which indicated the changes of AChE insensitivity, MFO activity or GSTs activity only played some roles in different stages of the resistance change.
基金funding from the National Institutes of Health through an institutional Harvard Trauma Inflammation T32 educational training grant(4T32GM103702–04)Elliot B.Tapper receives funding from the National Institutes of Health through the Michigan Institute for Clinical and Health Research(KL2TR002241).
文摘Cirrhosis is associated with debilitating complications that significantly impact on a patient’s physical function and reduce quality of life.Owing to highly prevalent sarcopenia,malnutrition and hepatic encephalopathy,functional impairment or frailty is a common complication of cirrhosis.Frailty in turn increases the patient’s risk of hospitalization,accidental falls and fractures,and death.The management of frailty and its associated adverse effects is imperative in improving the overall prognosis of patients with advanced liver disease.The cornerstone of therapy revolves around optimizing physical function with appropriate nutrition and exercise.Nutritional therapy with protein supplementation has shown significant benefit,while studies on exercise have been controversial.However,newly emerging studies trend towards a beneficial effect of physical exercise with improvement in quality of life.The implementation of technology in liver disease management shows future promise.Fitbits and other wearable devices can be used to help monitor a patient’s personal progress in physical exercise and nutritional optimization.Additionally,the progressive development of new smartphone applications to help aid in the diagnosis and monitoring of complications of cirrhosis provides a sophisticated avenue for improving care of patients with cirrhosis.